An experimental study of hypersonic flow development in a pipe

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t(luyverweg 1 - 2629 HS DELFT

AN EXPERIMENTAL STUDY OF HYPERSONIC

FLOW DEVELOPMENT IN A PIPE

by

J

~

P. Sislian, Z. He, and R. L. Descham bault

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AN EXPERIMENTAL STUDY OF HYPERSONIC

FLOW DEVELOPMENT IN A PIPE

by

J. P. Sislian, Z. He, and R. L. Deschambault

Subrnittcd Junc 1991

August 1991

©InstilulC ror Aemspace Studies 1991

UTIAS Technical Note No. 275

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ACKNOWLEDGEMENTS

The authors wish to thank Dr. P. A. Sullivan for a critical reading of the manuscript.

This research was financially supported by Johns Hopkins University Applied Physics Laboratory, the U.S. Air Force Wright Aeronautical Laboratories under Contract F33615-87-2748, and the Natural Sciences and Engineering Research Council Canada under Orant No. SEF8703. Their support is gratefully acknowledged.

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ABSTRACT

The present investigation is coneerned with the understanding of the strueture of the hypersonie flow developed in a eireular pipe. The experiments were eondueted in the UTIASlRyerson Gun Tunnel at a free-jet Maeh number of 8.30 and Reynolds number based on the pipe diameter, Re = 2.44x 1 06. Wan statie pressure, as weIl as in-stream statie and pitot pressure measurements at several seetions in the pipe, shed some light into the physieal nature of the eonsidered flow. These

preliminary measurements indieate that shocks generated in the pipe flow are primarily oblique.

Mensurements near the pipe axis and in wave structures presented some diffieulties. Further work is needed to clarify eertain fentures of the investigated flow.

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1. INTRODUCTION AND OBJECTIVES

The structure of a supersonic flow in a duet has important implications in the design and operation of wind tunnel diffusers, in lets and induction systems of hypersonic airbreathing engines. There have been numerous experimental investigations of the viscous-inviscid interactions that occur in such confined flows. These have inc1uded the influence of such parameters as: the Mach number of the oncoming flow, pipe diameter and length, and the presence or absence of an upstream boundary layer. Depending on the thickness of the boundary layers present, various shock-wave configurations were observed. Boundary layers formed in these flows, as weIl as shock wave/boundary layer interactions have also been investigated. The free-stream Mach number considered in all of these investigations did not exceed four (see Refs. 1-11).

Wall pressure distributions in long circular ducts, LID

=

42-53, over a range of oncoming Mach numbers 1.8 ~ Moo ~ 4.2, were measured in an early paper by Neumann and Lustwerk (Ref. 1). The purpose of the investigation was to determine the optimum length for the design of the throat section of a wind tunnel diffuser. It was found that when shocks were generated in the ducts, the pressure rise extended over a length of 8-12 tube diameters. In a subsequent paper (Ref. 2) Lustwerk studied the influence of the boundary-layer thickness at the beginning of the shock system formed in a sharp leading edge rectangular duct in a Mach 2.05 wind tunnel. Schlieren pictures of the flow showed that with no upstream boundary layer, a plane normal shock wave was formed. As the boundary layer thickened, a series of plane or lambda shocks occurred. Further thickening of the boundary layer generated oblique shock waves. For a lower free-stream Mach number of 1.5, Richmond and Goldstein (Ref. 3) measured streamwise wall static pressure and centreline total pressure distributions in an expanding rectangular duet in order to infer friction factor and heat transfer coefficients for a turbulent supersonic channel flow that develops at a nominally constant core-flow Mach number without shocks. The structure of shock waves generated in rectangular ducts at free-stream Mach numbers Moo

=

1.6-2.5 was also studied in Ref. 4. It was shown that various shock-wave structures with pressure jumps up nearly to normal shock value could be generated. In Ref. 5, shock stabilization in constant-area ducts, for Mach numbers of 1.76-2.51, was investigated as applied to the induction system for turbojet inlets.

Test results of supersonic combustion ramjets in hypersonic free jets and in direct-connect mode showed (see Ref. 6) that combustion in a supersonic flow generates a shock train in the upstream flow and that an isolator duct of prescribed length is requirèd to stabilize the wave train and prevent combustion-induced disturbances to affect the flow in

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the engine inlet. The flow structure in such isolator ducts was investigated in Refs. 7-9. Wall statie and in-stream pitot pressure distributions, as well as wall shear stress, were measured at free-stream Mach numbers of 1.13 ~ Moo ~ 2.72 and at a Reynolds number based on upstream boundary-layer momentum thickness of 5x 1 0 3 ~ Ree ~ 6x 104 in a cylindrieal duet. Based on an analysis of these measurements, the character of the shock-wave strueture was shown to be oblique rather than normal, with the flow remaining supersonic downstream of the shock system. The influence of the Mach number, Reynolds number Ree, duet diameter and upstream boundary layer momentum thickness, 8, on pressure recovery was also studied. It was shown th at for a given pressure ratio aeross the disturbance the distance over which the pressure rise is spread vanes approximately directly with the product 8112D1(2 and inversely with

(M~-1)Re~/4.

I n a more recent paper Om and Childs (Ref. 10) have obtained detailed pitot, statie and wall pressure measurements for multiple shock wave-turbulent boundary layer interactions in a circular duet at a freestream Mach number of 1.49 and at a unit Reynolds number of 4.90x 1 06 per meter. Their resuIts show the formation of a series of normal shock waves with successively decreasing strength and with decreasing distance between the successive shock waves. The overall pressure recovery is much lower than the single normal shock pressure recovery at the same free-stream Mach number. Lately, a detailed experimental study of the supersonic turbulent flow development in a square duet was reported in Ref. 11, over a development length 0 ~ LID ~ 20 for a uniform flow with a Maeh 3.9 condition at the duet in1et. Total pressure contours and local skin friction coefficient distributions showed that the flow develops in a manner similar to th at observed for the incompressible case.

The objective of the present research effort is to gain a better understanding of the physical nature of the flow developing in a circular pipe at a flow Mach number M

=

8.30. Data obtained provide a picture of the mean flow behaviour and the shock-wave system formed within a constant-area pipe, from essentially uniform mean flow conditions at the inlet. The presented results may guide the development of computational fluid dynamic codes applicable to hypersonic pipe flows.

2. FLOW FACILITY, UTIAS GUN TUNNEL

A schematic diagram of the major tunnel components is shown in Fig. 1. The reservoir, or driver (1), is charged to a nominal pressure of 20.5 MPa by a compressor. A

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rupturing the diaphragms. A free-moving piston is accelerated down a 76.2 mm inside diameter 6.2 m long barrel (4) to compress and adiabatically heat the air. This reservoir of heated air then flows through a convergent-divergent nozzle (6) into an open-jet test section (7). Typieal running times are 10-40 milliseconds, and the maximum effective reservoir pressure is 24 MPa and reservoir temperatures can be up to 13ooK. The air in the reservoir is isolated from the rest of the tunnel af ter a run by a remotely actuated balI valve (2). The tunnel firing sequence is automatic and fail-safe. Currently the faciHty uses a Mach 8.30 contoured nozzle with an exit diameter of 217 mmo In any given run, the data acquisition system can record up to twelve channels of experimental data. A photograph of the facility from the high-pressure end looking toward the test section is shown in Fig. 2. A view of the Mach 8.30 contoured nozzle and test section is given in Fig. 3. Tunnel specifications are found in Table 1. A history of the barrel pressure just upstream of the throat 'Of the nozzle is shown in Fig. 4. Due to the double diaphragm technique and accurate setting of initial conditions, it has been shown that these histories are highly repeatable. The double diaphragm technique allows the operator to choose when the tunnel is fired. The pressure history shows a small jump (first reflected shock from the nozzle throat) and then much larger spikes as the piston stops and actually reverses direction. The motion of the piston settles down and a relatively flat, slowly increasing pressure is observed until the run ends and the pressure drops.

Measurements of the free-stream pitot pressures for 200, 400, 600, and 800 KPa initial barrel pressures are shown in Fig. 5. These traces give a good indication of the usabie run times in the tunnel. In Fig. 6, a pitot pressure survey of the nozzle exit at two different positions is illustrated. A relatively flat core flow of approximately 150 mm is observed at both stations. A statie pressure history in the free-stream is shown in Fig. 7 (sec also Fig. 17). A heat transfer history of a platinum thin-film resistance thermometer located at the stagnation point of a sphere with a cylindrical afterbody is shown in Fig. 8.

The tunnel properties are highly repeatable and the flow is very clean. This is evidenced by the loss of only two pressure transducers in over 400 runs. Recent stagnation point heat transfer measurements show th in-film resistance thermometers changing in resistance by less than 1 % af ter a run. Cleanliness is assured by the swabbing of the barrel after every run and the use of lexan throat plugs to isolate the test section from the barrel. Originally nylon or teflon plugs were used, but had the tendency to shatter into small pieces producing large amounts of debris. The lexan plugs deform and sometimes tear, but resist breaking into many small pieces.

Tunneloperations are controlled from a central con trol panel. All high-pressure Hnes are isolated from the panel, increasing operator safety. The firing sequence is totally

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automatic with all valves opened and closed in the correct order at the proper time. With the availahle compressor and vacuum pump the tunnel can be turned around in as litde as 35 minutes for the next run. Depending on the complexity of the model being studied, 8 to 10 runs a day is reasonable, over extended hours as many as 17 runs have been accomplished in one day.

For the present experiments a new 250 mm diameter viewport has been incorporated between the test section and the dump tank in order to visualize the pipe exit flow by schlieren photography. The compound test section is shown in Fig. 9.

3. THE EXPERIMENTAL MODEL

A 76.2 mm (3") inside diameter and 762 mm (30") long constant area brass pipe having a 2.8 mm (0.115") wall thickness was used for the present investigation. In order to minimize leading edge effects on the flow within the pipe, shallow 3° angle wedge seetions were used to form the pipe leading edge with a tip thickness of 0.127 mm (0.005"). The brass provides for material strength and ease in forming the sharp leading edge.

The front end of the pipe is fixed to the test section floor via a support which can rotate around horizontal and vertical axes. The aft end is mounted through a similar support on a traversing mechanism whieh moves the aft end of the pipe in the vertical and lateral directions with a positioning accuracy of 0.4 mm (1/64") (see Fig. 10). This traversing mechanism and two pairs of differential pressure transducers for four wan statie

pressure taps cireumferentially located at 1.27 cm (0.5") from the aft end of the pipe are

used to aIign the pipe axis with the direction of the test section flow by changing its angles of attack and yaw. A photograph of the pipe mounted in the test section of the gun tunnel is shown in Fig. 11.

4. INSTRUMENTATION

4.1 Pitot and Statie Pressure Probes

Since visualization of the internal pipe flow is impossible, it is neeessary to reeonstruct the flow from pressure measurements. Therefore, the pipe is instrumented primarily for wan statie pressure and in-stream statie and pitot pressure measurements.

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shock waves that eould be generated in the pipe, statie pressure taps were plaeed at 2.54 cm

(1") intervals along the wall of the pipe. Their loeations along the pipe are shown in Fig.

12. The geometry of the orifiee and eavity of the statie pressure tap, as well as its dimensions, are shown in Fig. 13. In Ref. 12 it is noted th at the statie pressure error for this type of tap is nearly zero. The design and dimensions of the pitot pressure probe used to determine in-stream total pressures, inc1uding the wall boundary region, is presented in Fig. 14. The flattened tip reduees the displacement error near the wall. The performance of this probe was eompared to the output of the more eonventional straight pitot probe with a eireular orifiee shown in Fig. 15(a). Figure 15(b ) depiets the pitot pressure traees obtained with these two probes in the highly non-uniform and complex flowfield at the aft seeond test section of the gun tunnel (with the pipe removed, see Fig. 9). Although the responses seem to be slightly different, the steady portion of the traces agree quite weIl.

For in-stream statie pressure measurements three different designs were eonsidered (Fig. 16). A total of eight probes were fabrieated: three based on design (a) with the statie pressure holes loeated at 10, 15 and 20 extern al probe diameters downstream of the eone-cylinder junetion; two based on design (b) with two holes loeated 16 probe diameters downstream of the eone-eylinder junetion at angles (0 = ±70· and (0 = ±90· from the vertical plane; and three probes based on design (e) with three or two holes loeated 16 diameters downstream of the probe shoulder and at angles 120· for the three-hole case, and ±70· and ±90" for the two-hole case. All other relevant dimensions are given in Fig. 16. These probes were tested in the tunnel test seetion. Figure 17 eontains the statie pressure traces obtained by these probes, as weIl as the eorresponding barr~l (reservoir) pressure traces reeorded during the tests. Also shown in Fig. 17 is a third set of traces generated by dividing the measured statie pressure by the corresponding barrel pressure (the magnitude of this ratio multiplied by 10 can be read on the right ordinate of the plots). It ean be seen that the 16 gauge, 16 diameters, three hole at ± 120· probe records of statie pressure and statie to barrel pressure ratio (Exp. 3-081) in Fig. 17(f) exhibit the best steadiness.

Therefore, this statie probe was ehosen for in-stream statie pressure measurements in the pipe. Test seetion Maeh numbers derived from these statie pressure probe results are reported in Table 3.

Assuming the flow inside the pipe to be perfeetly axisymmetrie, in-stream statie and pitot pressure measurements were performed by inserting,a t eaeh measuring section, two statie or two pitot pressure probes into the pipe via two diametrieally opposed slots in the vertieal symmetry plane of the pipe. The probes were moved vertieally by a traversing meehanism. Pitot and statie pressure probes with distanees from the probe stem eentreline to the measuring orifiees of 63.5 mm (2.5") were eonstrueted (Fig. 18). Statie or pitot

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pressure measurements were performed simultaneously at two points located in the upper and lower halves of the section. Seventeen such double measurements of statie and pitot pressures were taken at each section. For measurements at the duet exit section, the probes were mounted on a probe holder attached to a vertical traverse (see Fig. 19).

4.2 Schlieren System

To visualize the flow over the pipe model a schlieren system was employed. The schlieren was set up in a standard two-mirror arrangement with a shaped light souree at the focus of the first mirror and a knife edge at the focus of the second mirror. Each mirror was 23 cm in diameter and had a focal length of approximately 1.83 m. The mirrors were approximately 7 mapart and the system could be adjusted to provide excellent sensitivity. A standard 10.2 x 12.7 cm view camera capable of holding sheet film or polaroid film was used to record the schlieren photographs. The light source used was a 4-pulse spark source discharging through argon gas. This provided spark stability and a duration of 750 ns. For this investigation only one spark was used.

5. DATA ACQUISITION AND PROCESSING SYSTEM

5.1 Transducers and Signa) Conditioning

During the course of experiments, pressure histories were recorded in a large number of locations. Several types and models of pressure transducers were used during the investigation. They are described below.

The pressure history in the gun barrel was measured with a PCB Model 113A22 piezoelectric pressure transducer with a range of 0 to 35 MPa. Pressure is measured with respect to the initial pressure seen by the transducer. The transducer has an excellent frequency response, a short rise time of 1 ~s, and aresonant frequency of 500 kHz. The associated power supply, PCB Model 494A amplifier, also provided selectable filters to provide some signal conditioning. Al1 barrel pressure histories in this investigation were filtered at a cutoff frequency of 20 kHz.

Statie pressure histories along the wall were measured using primarily Endevco Model 851 OB-5 piezoresistive transducers with a range of 0 to 5 psi (0 to 35 kPa). These transducers have excel1ent risetime response and a typical resonant frequency of 85 kHz and have an integral 10-32 thread to allow easy mounting. These transducers are

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and clipped when the test section pressure stabilized to its lowest value, typically 50 Pa. The transducers were powered by their associated signal conditioning equipment, an Endevco Model 4423 signal conditioner/4225 power supply. The signal conditioner had adjustable gains of 5, 10, 20 and 50. Signals were filtered using UTIAS filters built especially for this purpose. The design used a classic 2-pole Butterworth low-pass active filter using precision components to obtain a corner frequency (-3 dB) of 20 kHz and roll-off of -12 dB/octave.

Endevco Model 8510-50 (0 to 350 kPa, resonant frequency of 270 kHz) and Model 8530-15 (0 to 100 kPa, resonant frequency of 120 kHz) were used to measure the pitot pressure at different points in the flowfield. These transducers have similar characteristics to the 8510-5, and are physically identical in construction. The 8530's are absolute reference transducers and hence do not have reference tubes. Measurements of the static pressure surveys inside the pipe were accomplished with Endevco Model 8514-10 (0 to 70 kPa, resonant frequency of 140 kHz) transducers. The physical construction of these transducers allowed them to be placed very close to the stat ic probes used in the survey. The transducers are very small, have no thread, are cylindrical in shape, and they are mounted using silicon rubber adhesive. All the Endevco transducers use the same signal conditioning and filtering described previously.

5.2 Transient Recorders, Computer, and Software

All pressure histories were recorded by Pacific Transient Recorders Model 9830. This is a modular multi-channel system which permits easy expansion of additional recorders. In this study up to 10 channels were used to record the data. Each transient recorder had a resolution of 12 bits to ensure a high fidelity record of the signal. Each channel had ~4 K words of memory which could be segmented into 16 parts. Each segment could he programmed to he pre- or post-trigger and have its own sampling rate. The recorders were capable of a maximum of 1 MHz sample rate. For this investigation the first segment of memory was defined as a pre-trigger with a sample rate of 62.5 kHz and the last 15 segments as post-trigger with a sample rate of 250 kHz. For typical run times in

•

the gun tunnel for this experiment, this gave approximately 12,000 points of useful data. The transient recorders are capable of totally independent operation and have battery-backed-up memory capabilities allowing the data to remain intact for 100 hours if power to the units is interrupted. An AT c1ass MS-DOS based microcomputer (AST Premium 286) was used to transfer data from the recorders over an IEEE-488 bus using proprietary software supplied by Pacific. The data transfers were very fast, of the order of

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15 seconds per channel and the program provided facilities for output in engineering units, programming of the transient recorders pre- and post-trigger rate profiles, file maintenance, real-time signal monitoring, and graphical output of data, just to name a few. A translation program to convert the raw data to ASCII was written to all ow further analysis of the data with standard application software packages found in the microcomputer, such as graphics packages, spreadsheets, etc. Each raw data file was 132 kb in length, hence it hecame apparent that the initial40 Mb drive in the AST would he inadequate. A 330 Mb drive was installed and partitioned into a 50 Mb and a 280 Mb drive under MS-DOS 4.01 which allowed ample space for the large amount of data files generated by the experiments. The computer had an EGA graphics adapter with enhanced colour monitor, 1 Mb of RAM, a math co-processor, dot-matrix printer, and an 8 pen high-resolution plotter.

5.3 Data Analysis Techniques

The raw data files contained approximately 64,000 data points, each consisting of a 12-bit word representing a voltage at a particular time. For the present investigation, the

time interval for each point af ter trigger was 4 ~s or 250,000 samples/second. During the

experiments, the various pressure histories started approximately 7 ms after trigger and ran for about 40 ms. Hence, over 12,000 data points were obtained during the time of interest. For the purposes of the present experiments, only every 20th point was used (over 600 data points) in the analysis. Averages were taken over a 10 ms span selected to he more or

less constant for the duration of the run. This was sufficient for the majority of cases.

6. _{EXPERIMENTAL PROCEDURE}

Experiments began with the installation of instrumentation on the pipe. The model was then placed into the gun tunnel test section and bolted firmly into the floor of the test section. All instrumentation cables were brought to vacuum tight connectors inside the test section and ran back to the transducer amplifiers and signal conditioning equipment which

were hooked into the data acquisition system. _{Programming of the system began at this}

point. The engineering unit's conversion equations were programmed into each individual

,_{channel of the data acquisition system. The system was then put into a real-time sampling}

mode to verify that the equations were correct using test signals generated by the transducer's amplifiers. At this point the data acquisition system was ready to acquire data. The tunnel itself was then prepared for use. The on-site high pressure compressor

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lexan plug was inserted into the nozzle throat. The end facing upstream was angled to force the plug to fly around the model.

The pressure in the test section was brought down its nominal operating val ue (50 Pa) by a mechanical vacuum pump. The gun barrel was pressurized to 400 kPa with medical grade air supplied by a standard gas cylinder. The completion of the loading procedure was handled by a regulator and flow-control valves which pressurized the eh amber bet ween the two diaphragms to 10.5 MPa and the eh amber between the upstream diaphragm and the main isolating balI valve to 20.6 MPa using air from the gun tunnel reservoir. Once complete, the tunnel was loaded and ready to fire. From this point all operation was automatic, the various valves were opened and closed in the correct sequence by pushing the fire button. Af ter the run, all vents were opened to all ow air back into the test section and to depressurize the gun barrel.

As mentioned above the pipe was aligned with the nozzle free jet flow direction by changing its angles of attack and yaw and by monitoring the wall pressures at four circumferentially located pressure taps at the aft end of the pipe (see Fig. 20). This figure also dep iets the four wall pressure traces at alignment. The alignment of the pipe was further fine-tuned by comparing, at each measuring section, the pitot pressure magnitudes at two symmetrical points, with respect to the axis (along the vertical diameter).

7. EXPERIMENTAL RESULTS

Schlieren photographs were taken of the flow at the entrance and the exit of the pipe. These can be seen in Figs. 21 and 22. Note that the model can be seen in Fig. 22 to have started properly during a run. At the exit, the flow is seen to be relatively simple with no waves from the outside of the pipe being generated. Only two shock waves and a boundary layer are seen coming from the exit of the pipe.

Three gun tunnel runs were required to measure the entire wall pressure distribution. During each run, pressures at only eight locations were recorded, with at least pressures at one or two locations being repeatedly measured to check the reproducibility of the results. A typical measured wall pressure distribution is depicted in Fig. 23. The wall pressure increases slowly but steadily from the pipe leading edge to a peak value of twice the free stream statie pressure at xlD

=

5.7, characteristic of a shock-boundary layer interaction. Tt then decreases rapidly af ter the interaction zone, and the flow seems to expand in this region. Thereafter it slowly decreases to its pre-interaction value. A ~light

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In-stream statie and pitot pressures were measured at distances x!D

=

2.38, 3.0, 5.0,5.67,6.33, 8.0, 8.65 and 9.83 from the pipe leading edge. Measurements proceeded from seetion x!D

=

9.83 forward. Statie pressure traces generated by the employed probe at various locations in the pipe flow are shown in Fig. 24. The statie pressure probe response in Fig. 24(a) is representative of most performed measurements. However, in some instanees, the probe was probably very close to a wave structure or in the transition region of the wave. A statie pressure traee representative of this region is shown in Fig. 24(b). Moreover, pitot andfor statie pressure traces obtained near the axis of symmetry at some sections depicted some flow unsteadiness (see Fig. 24(e)). As it was not possible to obtain a meaningful average, values of statie pressures in these regions of the flow are not reported.

The distributions of measured ratios of local statie to (average constant) free stream statie pressures and the loeal total pressure (determined from the Rayleigh pitot tube equations) to average, constant, free stream total pressure are presented in Figs. 25-32. Near the wall statie pressure measurements at x/D

=

5.0, 6.33, 8.0, 8.65 and 9.8 were within ±5% of the values obtained from wall pressure taps at these locations. Therefore, it was assumed that the statie pressure is constant in those near the wall regions (represented by white squares in these figures). It was not possible to obtain meaningful near wall statie pressure measurements at all other sections.

A distinct pressure jump, charaeteristie of a shock, is clearly seen in all statie and total pressure profil es. At section x!D

=

8.0, Fig. 30, two such jumps are visible. The pressure jump at section x!D

=

2.4 is radially located in the vicinity of

y!D -

0.23. At subsequent sections, it seems to move radially towards the wall up to the section x!D

=

5.7, Fig. 28, where shock-boundary layer type interaction takes place (/Fig. 23). Thereafter, it slowly but steadily moves away from the wall and disappears, together with the second shock formed near the axis of the pipe (Fig. 30), at the exit section of the pipe. The shocks generated in the flow seem to be oblique, with possible normal shocks in central portions of the pipe where these oblique shocks reflect off the axis of symmetry. AIso, tot al pressure profiles near the pipe wall give an insight into the boundary layer thiekness which notably inereases in the downstream portion of the pipe flow. Presented data exhibit some scatter in some regions of the flow whieh does not exceed -10% (see, for example Figs. 27, 28 and 32). Numerical values of statie pressure and total pressure ratios, as weIl as flow Mach numbers, are given in Table 4.

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8. CONCLUSION AND RECOMMENDATIONS FOR

FUTURE WORK

Preliminary results for in-stream statie and pitot pressures presented above need further refinement, partieularly in the vicinity of the pipe axis. Other statie pressure probe designs should be tested. Measurements should he performed at additional sections in order to obtain a more detailed structure of the confined flow. Finally, the present investigation could he extended to a duet of rectangular cross-section.

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REFERENCES

1. E. P. Neumann and F. Lustwerk, "Supersonic Diffusers for Wind Tunnels," 1. Appl. Mech., No. 6, 1949, pp. 195-202.

2. F. Lustwerk, "The Influence of Boundary Layer on the Normal Shock Configuration," MIT, Cambridge, Massachusetts, Meteor Report No. 9661, Sept. 1950.

3. 1. R. Kenneth and R. Goldstein, "Fully Developed Turbulent Supersonic Flow in a Rectangular Duct," AIAA 1., No. 8, 1966, pp. 1331-1336.

4. A. A. Fejer, et al, "An Investigation of Constant Area Supersonic Flow Diffusion," ARL 64-81, Aerospace Research Labs., Wright-Patterson Air Force Base, Ohio, 1965.

5. G. H. McLafferty, E. L. Krasnoff, E. D. Ranard, W. G. Rose, and R. D. Vergara, "Investigation of Turbojet Inlet Design Parameters," United Aircraft Corp., East Hartford, Connecticut, Report R-0790-13, Dec. 1955.

6. F. S. Billig, G. L. Dugger, and P. J. Waltrup, "Inlet-Combustor Interface Problems in Scramjet Engines," 1 st International Symposium on Air Breathing Engines, International Airbreathing Propulsion Committee, Marseilles, France, June 1972. 7. P. 1. Waltrup and F. S. Billig, "Precombustion Shock Structure in Scramjet Engines,"

AIAA Paper 72-1181, New Orleans, Louisiana, 1972.

8. P. J. Waltrup and F. S. Billig, "Structure of Shock Waves i!1 Cylindrical Ducts," AIAA J., Vol. 11, No. 10, 1973, pp. 1404-1408.

9. P. J Waltrup and J. M. Cameron, "Wall Shear and Boundary-Layer Measurements in Shock Separated Flow," AIAA J., Vol. 12, No. 6, June 1974, pp. 878-880.

10. D. Om and M. E. Childs, "An Experimental Investigation of Multiple Shock Waverrurbulent Boundary Layer Interactions in a Circular Duct," AIAA Preprint No. 83, 1744, 1983.

11. F. B. Gessner, S. D. Ferguson, and C. M. Lo, "Experiments on Supersonic Turbulent Flow Development in a Square Duct," AIAA J., 1987, 25, No. 5, pp. 690-697.

12. S. H. Chue, "Pressure Probes for Fluid Measurements," Prog. Aerospace Sci., 16, No. 2, 1975, pp. 147-223.

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Table 1.

Hypersonic Gun Tunnel -

Specifications

Physieal Dimensions Tunnellength 16m Gun barrellength 6.1 m Gun barrel ID 76.2 mm

.

... . .... ~ ... ~ ... Test Section Width 635mm Height 610mm I:~!:'.s.!h, 610mm _..._._... Nozzle exit diameter 217mm

Piston material Aluminum 7075-T6

Piston mass 96 g

Initial Tunnel Operating Conditions

Resetvoir pressure 20.5 ± 0.2 MPa Barrel pressure 100 to 800 kPa Test seetion pressure 50± 10 Pa Tunnel Flow Properties

Freestream pitot pressure 183 kPa Freestream statie pressure 2.13 kPa

Stagnation pressure upstream of the 25.5 ± 0.05 (current nozzle) throat

. ... ~ ••. _ ___ ... _ _ • •••• n ... _ _ ...-... ...

UsabIe Flow Test Time

200 kPa in barrel 10 ms 400 kPa in barrel 30ms 600 kPa in barrel 40ms 800 kPa in barrel 40ms

• _ _ • •• ' • •••••• ••• • ••• • • ••••• • •• · .... . . ... n ... _ _ •

.

...

.

..

...

.

Total Temperatures and Reynolds Numbers (estimates)

Tt (K) Re (per meter)

200 kPa in barrel 1220 23x1()6

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Table 2. Tunnel

Diagnostics and Instrumentation

Schlieren Photography Two view ports (300 mm dia)

250 mm field of view

Four spark light source (750 ns pulses)

A vailable Instrumentation Pressure transducers

Platinum thin-film resistance thermometers Thermocouples

Force transducers Accelerometers

Data Acquisition System 10 channels

1 MHz (max) sample rate 12 bit resolution

64 K words of data per channel 2 channels

6 MHz (max) sample rate 8 bit resolution

16 K words of data per channel ..

Tunnel Operation DutyCycle

8 to 10 runs per 8 hour shift

... • • • • 0 0 #

Tunnel Con trol System Remote valve control

Remote digital pressure indicators

No high pressure lines located at con trol panel Fully automatic valve sequencing when fired Fail-safe operation during pneumatic or electrical

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Table 3.

Test seetion Maeh numher derived trom eight different statie

pressure probe results for an ave rage reservoir (stagnation)

pteSSllre Po ::.: 25.5 MPa. Referenee test seetion Mach number

M_REF :-.: 8. 24, ganuna = 1. 4 •

statie _{(MTs-MooREF)!MREF}

Test No. Probe Pressure _MTS

(kPa) (%) 3-069 ST-19-15D- 4H±90"±180· 2. 36 8.12 1.5 3-:)70 ST-19-10D-4Ht90"±180· 2.49 8.06 2.1 3 --0'7 'l ST-19-20D-4H±90"±180· 2.15 8.24 0_0 3-080 ST-16-16D-2H±90 ' 2.59 8.01 2.8 3--078 ST-16-16D-2H±70· 2.33 8.14 1.2 3-081 ST-16-16D-3H±120· 2.15 8.24 0.0 3-083 ST-16-16D-2H±70· 2.27 8.18 0.1 3-084 ST-16-16D-2H±90· 2.22 8.20 0.5

(21)

Table

4.

(x/D

=

2.4, GAMMA

=

1.4) '.lID 0.458.3 0.4375 0.4167 0.3750 [).3::;::'3 0.2917 0.2500 0.2292 0.2083 0.187'':' 0.1771 0.1563 0.1354 0.1146 0.0938 0.0833 0.0729 0.0625 0.0521 0.0417 0.0313 0.0208 0.0104 Legend: pI (k?a) 2.16 3.31 4.32 6.48 8.35 8.92 9.53

****

3.69 3.64 3.80 3.74 3.:19 3.64 3.61 3.32 3.30 3.80

****

PI (MPa) 23.39 8.76 5.57 13.27 5.10 3.57 2.38

****

**

*

13.18 9.44 8.50 8.00 8.44 7.94 8.36 9.77 9.28 6.15

****

P2 (kPa) 184.7 185.1. 189.4 329.7 286.3 265.0 240.1 232.8 227.0 223.8 199.6 198.8 192.9 191.1 189.1 191.2 189.3 185.5 179.5 179.5 131.3 55.6 8.3 pI/pO 1.051 1.642 2.103 3.153 4.066 4.343 4.641

*****

1. 795 1.770 1.848 1.819 1. 749 1. 773 1. 759 1.613 1.604 1.851

*****

pO - freestrerun statie pressure (avg. value

=

2.06 kpa) pl - loeal statie pressure

PO _. reservoir total pressure (avg. value

=

26.7 MPa) PI - loeal total pressure

P2 - loeal pitot pressure Ml - loeal Mach number

P1/PO 0.8753 0.3280 0.2083 0.4967 0.1909 0.1338 0.0890

******

0.4933 0.3534 0.3182 0.2994 0.3159 0.2970 0.3129 0.3655 0.3474 0.2303

******

u - data could not he time aver'aged, caleulated, or' was not measured

Ml 8.1.29 6.501 5.804 6.258 5.124 4.765 4.382

*****

6.840 6.501 6.349 6.302 6.397 6.321 6.382 6.633 6.586 6.024

*****

(22)

Table 4. Continued

(x/D

=

3.0, GAMMA

=

1. 4)

y/D pI PI P2 pI/pO PI/PO MI

(kPa) (MPa) (kPa)

0.3542 8.76 3.68 264.6 4.263 0.1379 4.806 0.3125 9.14 2.75 246.0 4.451 0.1030 4.531 0.2708 9.21 2.21 229.0 4.484 0.0828 4.352 0.2500 9.13 2.14 225.1 4.446 0.0802 4.333 0.2292 9.80 1.77 220.0 4.769 0.0663 4.132 0.2083

_****

_219.6

_*****

_******

_*****

0.1771 3.66 9.27 199.3 1. 782 0.3468 6.474 0.1667 3.55 9.46 196.4 1. 727 0.3542 6.529 0.1563 3.66 9.32 199.5 1.779 0.3489 6.482 0.1.354 3.57 9.67 198.5 1.737 0.3618 6.545 0.1146 3.55 9.26 195.3 1.730 0.3465 6.504 0.0938 3.41 9.88 193.9 1.661 0.3698 6.615 0.0729 3.03 11.96 189.7 1.475 0.4476 6.947 0.0521 3.60 6.81 178.7 1.754 0.2548 6.177 0.0313

_****

_124.8

_*****

_******

_*****

0.0208

_****

_38.7

_*****

_******

_*****

0.0104

_****

_7.5

_*****

_******

_*****

Legend:

pO - _{freestream statie pressure (avg. value}

₌

_{2.06 kpa)} pl - loeal statie pressure

PO - reservoir total pressure _{(avg. value}

=

_{26.7 MPa)} P1 - loeal total pressure

P2 .- _{loeal pitot pressure} Ml - loeal Maeh number

(23)

Table 4. Continued

(x/D

=

5.0, GAMMA

=

1.4)

yjD pI PI P2 pI/pO PI/PO MI

(kPa) (MPa) (kPa)

0.5208 6.09 2.63 185.6 2.963 0.0985 4.828 0.5000 6.45 2.07 177.3 3.140 0.0773 4.581 0.4792 6.94 1.63 171.3 3.379 0.0612 4.337 0.4583 7.15 1.61 173.8 3.479 0.0604 4.304 0.4375 7.30 1.64 177 .1 3.553 0.0614 4.299 0.4167 7.40 1.60 177.2 3.601 0.0600 4.271 0.3958 7.61 1.64 181.9 3.704 0.0613 4.266 0.3750 7.80 1. 78 190.4 3.796 0.0667 4.313 0.3542 8.00 1.76 192.6 3.894 0.0658 4.282 0.3333 8.08 1.80 195.5 3.931 0.0675 4.294 0.3125 8.44 1. 73 198.5 4.110 0.0649 4.230 0.2917 8.64 1. 77 202.7 4.204 0.0661 4.226 0.2708 9.08 1.67 205.3 4.418 0.0626 4.147 0.2500 8.82 1.86 209.3 4.292 0.0696 4.250 0.2292 9.06 1.94 216.2 4.409 0.0726 4.262 0.2083 7.84 2.82 224.4 3.815 0.1056 4.677 0.1875 7.66 3.13 229.1 3.730 0.1171 4.781 0.1771 7.52 3.23 228.8 3.660 0.1210 4.824 0.1667 6.97 3.97 233.3 3.394 0.1484 5.062 0.1563 3.04 23.41 234.3 1.480 0.8763 7.712 0.1458 2.99 25.87 238.6 1.453 0.9685 7.854 0.1354 3.21 23.27 242.5 1.560 0.8708 7.642 0.1250 3.33 23.26 249.2 1.623 0.8706 7.595 0.1146 3.36 23.88 252.3 1.634 0.8937 7.618 0.1042 3.39 15.80 223.6 1.650 0.5913 7.131 0.0938 2.96 17.94 212.0 1.443 0.6713 7.428 0.0833 2.76 20.42 209.8 1.341 0.7642 7.666 0.0729 2.67 19.56 202.6 1.300 0.7319 7.652 0.0625 2.63 18.34 196.3 1.278 0.6865 7.597 0.0521 2.47 18.71 189.5 1.203 0.7004 7.691 0.0417

_****

11. 49'" 162.9'" 1. 203'" 0.4302" 7.129'" 0.0313

_****

0.94'" 72.3'" 1.203'" 0.0354" 4.726'" 0.0208

_****

0.11'" 32.5'" 1. 203'" 0.0042'" 3.139'" 0.0104

_****

0.01'" 10.1'" 1. 203'" 0.0004" 1. 664'" Legend:

pO _. _{freestream statie pressure (avg. value}

₌

2.06 kpa) pI - loeal statie pressure

=

_{26.7 MPa)}

PI -

loeal total pressure P2 - local pitot pressure

(24)

Table 4. Continued

(x/D

=

5.7, GAMMA

=

1.4)

y/D pI PI P2 pI/pO PI/PO MI

(kPa) (MPa) (kPa)

0.5208 6.34 2.69 192.1 3.084 0.1008 4.815 0.5000 6.96 2.25 192.0 3.389 0.0842 4.589 0.4792 7.24 1. 99 188.8 3.524 0.0746 4.459 0.4583 7.07 2.20 192.5 3.440 0.0825 4.560 0.4375 7.33 2.20 196.8 3.567 0.0822 4.527 0.4167 7.28 2.26 198.1 3.542 0.0848 4.558 0.3958 7.46 2.00 192.8 3.632 0.0750 4.440 0.3750 7.54 1.88 189.9 3.670 0.0704 4.381 0.3542 7.57 1. 75 185.7 3.685 0.0656 4.323 0.3333 7.80 1. 75 189.1 3.796 0.0654 4.298 0.3125 7.75 1.88 193.5 3.773 0.0705 4.361 0.2917 8.13 1. 83 197.6 3.957 0.0687 4.303 0.2708 8.20 1.81 197.7 3.990 0.0677 4.285 0.2500 8.65 1. 70 200.0 4.210 0.0635 4.195 0.2292 8.75 1. 69 201. 2 4.256 0.0633 4.184 0.2083 8.08 1.98 202.2 3.931 0.0741 4.368 0.1875 7.63 2.32 205.9 3.713 0.0867 4.538 0.1771 7.65 2.24 203.9 3.724 0.0839 4.510 0.1667 7.20 2 . .58 205.8 3.503 0.0967 4.674 0.1563 7.17 2.76 210.1 3.492 0.1032 4.731 0 . .1458 6.33 3.68 213.5 3.082 0.1378 5.081 0.1354 2.72 22.65 214.7 1.324 0.8479 7.806 0.1250 2.77 22.99 218.6 1.350 0.8607 7.801 0.1146 2.80 23.03 220.4 1.365 0.8620 7.789 0.1042 2.83 22.23 219.6 1.380 0.8320 7.734 0.0938 2.81 23.14 220.8 1.366 0.8662 7.794 0.0833 2.87 23.15 224.5 1.399 0.8665 7.766 0.0729 2.88 23.67 226.5 1.403 0.8861 7.790 0.0625 2.90 23.11 225.6 1.410 0.8649 7.754 0.0521

_****

_*****

_219.9

_*****

_******

_*****

0.0417

****

*****

214.0

*****

******

*****

0.0313

_****

_*****

_141.9

_*****

_******

_*****

0.0208

****

*****

63.2

*****

******

*****

0.0104

_****

_*****

_26.2

_*****

_******

_*****

Legend:

pO - freestream statie pressure (avg. value

=

2.06 kpa)

pI - loeal statie pressure

=

_{26.7 MPa)}

PI - loeal total pressure

P2 - loeal pitot pressure

Ml - loeal Maeh nurnber

(25)

Table 4. Continued

(x/D = 6.33, GAMMA = 1. 4)

y/D pI PI P2 pI/pO PI/PO Ml

(kPa) (MPa) (kPa)

0.5208 5.63 4.13 205.1 2.742 0.1544 5.284 0.5000 5.88 3.68 203.3 2.862 0.1379 5.146 0.4792 6.37 2.77 194.6 3.100 0.1037 4.834 0.4583 6.45 2.72 195.1 3.141 0.1019 4.808 0.4375 6.60 2.65 196.3 3.212 0.0993 4.768 0.41.67 6.63 2.82 200.9 3.225 0.1055 4.816 0.3958 6.61 2.98 204.5 3.216 0.1117 4.865 0.3750 6.84 2.63 200.4 3.330 0.0985 4.732 0.3542 6.82 2.72 202.2 3.320 0.1017 4.760 0.333.3 7.1.5 2.57 204.6 3.480 0.0962 4.675 0.3125 7.19 2.46 202.3 3.500 0.0921 4.636 0.2917 7.39 2.15 196.6 3.598 0.0805 4.504 0.2708 7.48 2.04 194.4 3.639 0.0763 4.453 0.2500 7.67 1. 96 194.8 3.732 0.0734 4.402 0.2292 7.89 1. 94 197.7 3.839 0.0726 4.370 0.2083 8.01 1.96 200.4 3.898 0.0734 4.367 0.1875 7.47 2.34 203.7 3.637 0.0874 4.562 0.1771 7.37 2.33 201.8 3.587 0.0873 4.572 0.1667 6.76 2.69 200.4 3.288 0.1009 4.762 0.1563 6.92 2.54 199.4 3.368 0.0950 4.692 0.1458 2.57 19.99 198.8 1.253 0.7481 7.722 0.1354 2.78 17.24 200.2 1.351 0.6452 7.459 0.1250 2.82 20.88 214.4 1.370 0.7815 7.667 0.1146 3.03 22.34 230.1 1.473 0.8360 7.661 0.1042 3.16 23.97 242.2 1.537 0.8972 7.695 0.0938 3.19 24.92 246.8 1.552 0.9329 7.730 0.0833 3.20 23.31 242.2 1.556 0.8726 7.647 0.0729 3.10 23.06 236.4 1.509 0.8629 7.670 0.0625 3.22 18.80 227.7 1.567 0.7036 7.387 0.0521

_****

13.64A 206.1~ _{1. 567}A 0.5104A 7.025~ 0.0417

_****

6.89~ _166.2A 1. 567A 0.2579A 6.302A 0.0313

_****

1.84A 108.0A 1. 567A 0.0609~ _5.068A 0.0208

_****

0.52A 69.4A 1. 567A 0.0195A 4.046~ 0.0104

_****

0.16A 44.3A 1.567A 0.0061A 3.214A Legend:

₌

_{2.06 kpa)}

pI - local statie pressure

=

_{26.7 MPa)} PI - loeal total pressure

(26)

Table 4. Continued

(x/D

=

8.0, GAMMA

=

1. 4)

yfD pI PI P2 pI/pO PI/PO Ml

(kPa) (MPa) (kPa)

0.5208 7.11 3.12 217.7 3.459 0.1167 4.841 0.5000 7.56 2.48 209.6 3.682 0.0927 4.600 0.4792 7.88 2.11 203.5 3.833 0.0791 4.440 0.4583 7.86 2.04 200.8 3.825 0.0765 4.414 0.4375 8.13 2.05 205.7 3.958 0.0768 4.391 0.4167

_****

_*****

_202.9

_*****

_******

_*****

0.3958

_****

_*****

_210.8

_*****

_******

_*****

0.3750

_****

_*****

_209.5

_*****

_******

_*****

0.3542 2.84 22.27 220.3 1.385 0.8336 7.732 0.3333 2.96 26.67 239.2 1.440 0.9983 7.902 0.3125

_****

_*****

_258.8

_*****

_******

_*****

0. 2917

_****

_*****

_262.9

_*****

_******

_*****

0.2708

_****

_*****

_258.3

_*****

_******

_*****

0.2500

_****

_*****

_263.0

_*****

_******

_*****

0.2292

_****

_*****

_256.0

_*****

_******

_*****

0.2083 6.54 5.48 249.0 3.184 0.2049 5.404 0.1875 6.37 5.10 238.8 3.099 0.1909 5.364 0.1771 6.30 4.82 232.7 3.066 0.1803 5.323 0.1667 6.38 4.83 234.9 3.105 0.1808 5.314 0.1563 6.23 4.91 232.4 3.032 0.1838 5.350 0.1458 5.92 5.36 231.1 2.879 0.2006 5.476 0.1354 2.87 22.75 223.2 1.398 0.8516 7.746 0.1250 2.86 22.14 220.6 1.391 0.8289 7.720 0.1146 2.82 20.20 212.2 1.370 0.7561 7.628 0.1042 2.82 17.85 204.4 1.372 0.6680 7.481 0.0938 2.68 16.24 191.8 1.305 0.6078 7.430 0.0833 2.70 9.83 164.6 1.312 0.3679 6.861 0.0729 2.61 6.88 143.8 1.269 0.2574 6.517 0.0625 2.54 4.16 120.2 1.234 0.1557 6.038 0.0521

_****

2.37~ 100.0~ _1.234" _0.0886" _5.503_" 0.0417

_****

1.30" 82.0 .... 1. 234" 0.0488 .... 4.975" 0.0313

_****

0.70 .... 66.1~ _{1. 234 ....} _0.0261" _{4.458 ....} 0.0208

_****

0.30 .... 48.5~ _{1. 234"} _{0.0111 ....} _{3.809 ....} 0.0104

_****

0.17 .... 39.0~ _{1. 234"} _0.0063" _3.404" Legend:

₌

_{2.06 kPa)} pI - loeal statie pressure

PO - r.eservoir total pressure _{(avg. value}

₌

_{26.7 MPa)} P1 - loeal total pressure

P2 - loeal pitot pressure MI - 1 oea 1 Maeh number

**

_.... - _{data eould not be time averaged, ealculated, or was not measured}

(27)

Table 4. Continued

(x/D = 8.65, GAMMA

=

1.4)

y/D

pI

PI P2 pI/pO PI/PO Ml

(kPa) (MPa) (kPa)

0.3750

_****

_*****

292.9

_*****

_******

_*****

0.3542

_****

_*****

285.5

_*****

_******

_*****

0.3333

_****

_*****

277 .9

_*****

_******

_*****

0.3125 5.82 8.10 261.7 2.834 0.3031 5.877 0.2917 5.82 7.58 255.9 2.830 0.2839 5.816 0.2708 5.80 7.40 253.4 2.822 0.2769 5.794 0.2500 5.92 6.35 244.6 2.883 0.2377 5.631 0.2292 6.04 5.55 237.1 2.941 0.2076 5.488 0.2083 6.28 5.05 235.7 3.055 0.1888 5.367 0.1875 6.03 5.05 229.6 2.936 0.1890 5.404 0.1771 5.78 5.13 224.2 2.811 0.1921 5.458 0.1667 5.75 5.20 224.6 2.800 0.1946 5.473 0.1563 2.74 25.10 222.8 1.335 0.9394 7.921 0.1458 2.71 25.61 222.4 1.320 0.9584 7.959 0.1354 2.73 25.19 222.1 1.327 0.9427 7.933 0.1250 2.70 23.22 215.3 1.315 0.8692 7.844 0.1146 2.64 20.92 205.5 1.287 0.7832 7.744 0.1042 2.68 16.77 193.7 1.304 0.6278 7.468 0.0938 2.50 14.20 175.2 1.215 0.5316 7.357 0.0833 2.63 7.31 147.5 1.281 0.2737 6.571 0.0729 2.67 4.21 124.8 1.298 0.1575 5.999 0.0625 2.66 2.77 108.9 1.296 0.1038 5.604 0.0521

****

1.64~ _91.5 _1.296~ 0.0614~ 5.132~ 0.0417

****

O.86~ _73.4 1.296~ _0.0322" 4.589~ 0.0313

****

0.48~ _59.9 1. 296~ 0.0181~ 4.137~ 0.0208

****

0.23~ _45.7 1.296~ 0.0088~ 3.602~ 0.0104

_****

0.14~ _36.8 _1.296~ 0.0051~ 3. 221 ~ l.egend:

pO - freestr.-eam statie pressure (avg. value

=

2.06 kpa) pl - loeal statie pressure

PO - reservoir total pressure (avg. value = 26.7 MPa) PI ·· loeal total pressure

P2 - loeal pitot pressure

MI - loeal Maeh number

**

- data could not he _{time averaged, cal cul ated , or was not measured}

~

(28)

Table 4. Continued

(x/D

=

9.8, GAMMA

=

1.4)

y/D pI PI P2 pI/pO PI/PO Ml

(kPa) (MPa) (kPa)

0.5208 3.46 26.98 267.4 1.682 1.0100 7.729 0.5000 3.53 26.27 269.3 1.720 0.9831 7.670 0.4792 3.70 24.03 270.3 1.800 0.8993 7.511 0.4583 3.46 26.50 265.9 1.682 0.9917 7.707 0.4375 3.54 25.46 267.2 1. 724 0.9529 7.630 0.4167 3.59 27.01 274.8 1. 749 1.0109 7.683 0.3958 3.68 26.93 279.1 1. 791 1.0079 7.652 0.3750 3.87 25.31 283.7 1.885 0.9473 7.518 0.3542 3.79 25.84 281.4 1.847 0.9673 7.567 0.3333 3.45 27.62 268.8 1.677 1.0337 7.760 0.3125 3.11 27.11 249.1 1.515 1.0147 7.860 0.2917 3.02 27.14 243.8 1.4ó8 1.0160 7.900 0.2708 2.89 27.17 236.9 1.408 1.0171 7.952 0.2500 2.82 26.28 230.4 1.373 0.9837 7.942 0.2292 2.83 25.65 229.0 1.376 0.9602 7.911 0.2083 2.95 26.23 237.4 1.435 0.9816 7.886 0.1875 2.94 25.03 233.5 1.430 0.9370 7.834 0.1771 2.94 22.63 226.2 1.429 0.8469 7.713 0.1667 2.83 25.93 230.1 1.378 0.9706 7.921 0.1563 2.84 25.13 228.3 1.382 0.9407 7.880 0.1458 2.86 24.75 228.4 1.392 0.9264 7.852 0.1354 2.82 24.51 225.3 1.370 0.9174 7.860 0.1250 2.74 22.22 214.5 1.334 0.8315 7.774 0.1146 2.68 20.72 206.8 1.305 0.7756 7.716 0.1042 2.81 15.71 195.9 1.366 0.5878 7.339 0.0938 2.85 11.35 179.0 1.388 0.4248 6.957 0.0833 2.85 8.75 164.7 1.385 0.3275 6.678 0.0729 2.94 4.70 138.2 1.431 0.1758 6.012 0.0625 2.92 2.65 114.0 1.419 0.0992 5.479 0.0521 2.93 1.20 87.8 1.427 0.0450 4.786 0.0417 2.95 0.77 75.4 1.434 0.0288 4.416 0.0313 2.93 0.36 57.0 1.426 0.0134 3.841 0.0208 2.98 0.19 44.7 1.452 0.0070 3.360 0.0104 2.98 0.10 34.7 1.452 0.0038 2.942 Legend:

pO - freestream statie pressure (avg. value

=

2.06 kpa) pI - loeal statie pressure

PO .- reservoir total pressure (avg. value

=

26.7 MPa) PI - loeal total pressure

P2 - loeal pitot pressure Ml - loeal Maeh n\.lTlber

(29)

Flgure 1.

Schematic diagram of the hypersonlc gun tunnel.

(1) high pressure reservoir (driver)

(2) remotely controlled lsolating bali valve

(3) double-dlaphragm station breeeh loek

(4) 6.1 m gun barrel

(5) nozzle throat station breech loek

(6) convergent-dlvergent nozzle

(30)

Fig. 2.

View of the hypersonic gun tunnel from the high

pressure reservoir looking downstream toward the test

section .

(31)

(32)

30~----~----~---~----~----~----~---.

25 . ___ .

___

.~

_____

._-+.

___

.

_.

__ ._

! ___

.

_

i ! ! ! i-··---···· ---

··r-

-··--_·

__

··

·_·_·l

.. ·_·_

·_

···

· _··

· ···

__

·

i I f ! ! i ~ ~ : J r . : :

m

20 . ___

. ___ ._ .

.

_~_

_

!_

I

1 1 ~

i

I

--.

-·_··--·_·-···r··--···_-···-·-····-· ....

l--·-····--·-..

···_··r····-·_· .. · ..

···-··· .. -··

'--' I i i ; ~ CD

15

i : . i i i ~ ---~---+-- ! -::J i i i Cl)

I

~

1

0 ---i---î---i---i---t----t---5

._____

---.----....j.-.---!---l---~-. _I _: _: _a i _, ___ . __ ~ ~ ~ î

l

! i i i ! ~ ~ ~ ~ 1 0+=~~+_----4i----~i----~i~----~l

____

~'

____

~

-0.005

0.000

0.005

0.010

0.015

0.020

0.025 Time (5)

Figure 4. Typical barrel pressure history in the hypersonic gun

tunnel. Initial barrel pressure of 400 kPa.

(33)

I

I I

---1---r \

- -~ I 1

V

,.ft'r 1

r

V

_\

J

"-ll.)o UI 0.1112 o.~ 0.114 o.~ o.bs

f\

,-==t----

-r

-

r--

~-~

1

/\1

!f'/

-i

1

I

1\

I

"-b.iJo 0.111 0.1R o.ls 0.114 0.11& 0.1Ie

1t t1m+----~~4~~----~---~---~----'~_+~---~

j,~--~J--~----~---+_----_+---+_+_--

-

~

0. 0. - t o l 1t t1~----~~~L---_4---~---~---_+~---~

j

1 c x H - - - 4 - - - f - - - + - - - + - - - + - - _ _ _ + _ _ 0. _ Q. (al 0. 0. 0.00

(34)

0

ai

a:

CD "-::J

m

CD "-ll. (ij

ë

§

~ Q..

8.0E-03

7.0E-03

6.0E-03

5.0E-03

4.0E

.

3.0E-03

2.0E-03

1.0E-03

O.OE+OO

-150

+0

Centerline Pitot Exit Survey

400 kPa Initial Barrel Pressure

• IIllt 'I ,: 111 • , ••

o l ' ~III.,

+

o

-100

-50

0

50

100

150 Nozzle

Exit

Coordinates (mm)

Figure

6. Pitot survey

of

the nozzla exit

at

10 and 195 mm

downstream of the exit. The centerline is

at

0 mmo

o

10mm

+

(35)

35 .---.-,--- --.-.. - . -.. ~---.--.--- .. - -.-.. --,----.. ---- -Exp.3-081 30 .. 1 ... . CiS 25-···· IJ.. :!

-

~ 20· ::l

~

0- 15+··· ~ as m 10· 5-··· ... . -, -.~ ... Barrel Pre~re

.

...

..

'

i

, _____

-..=jC,

~

-

~

,

. / ; _; Statie P _ressureT···_:· ...

-.-

~-.~

_{. .}_..

_=-"

.

_{. .}

_.

_...

_..

_.

~.=::-:-:' ... ~ ..

-i

..

=::~-::-:-:--:::'> .

.".c.-

.

d.

.

Statie/f3arrel • 10 ( ~ ) .

o

· -t

...Ab. ---....:"_ ... -1-.---._- u j - - - ---.. ----f---.. ---.... ---... ---.. _+ ... _ .. __ 0.00 0.01 0.02 0.03 0.04 · Time (s)

..

... CiS IJ.. 3.0 6 ~ ::l (IJ

~

-2.0 0-'1.0 '-0.0 0.05 o

N

en

(36)

'éi)'

E

.r:.

0

...,

Q) 0

c

as

Jii

Cl) Q)

a:

135

130

125

120 .

Stagnation Point Heat Transfer Model

400 kPa Initial Barrel Pressure

i

115 -

'---~+1---~---

I

110 - - - -

-+

I

105

0.000

0.010 !

_i i

i

.

-I

I

25.4 mm sphere with

cylindrical afterbody

1 mA

constant current

0.020

0.030

0.040 Time (s)·

o.oso

Figure

8. Resistanee history from a platinum thin film resistanee

(37)

Fig. 9.

Photo of the compound test section.

(38)

• FLOV DrRECTIO~

PROBE SUPPORT Pl PE MODEL ~

FRONT SUPPORT '> ,--,..,

ril

I ~ 'Î -,

ITll1i

i

I

·

1 i

i

1:,

!

I

I I 1 I I I

i',

! !

I

I I : :' ! j - - - 1 Ü ï i i

L_

.J

1-1

J~

I

l

TRANSDUCER COVERS

~

" ,

~

REAR SUPPORT TUNNEL FLOOR

1 \

_I _\ I \ I \ ( \.

\

l-.---r---'/

_,

\

GUN iUNNE:....~ NDZZLE

(39)

Fig. 11.

Photo of pipe in test section .

(40)

t

IIc II I .10 IS 15 IQ

I I I I

I I I I I I I I I I I I I

10 I' 11 17 " IS U 11 I1 1I1D • • 7 , I • , I $fCllDN 1 2 3

•

5 6 7 I 9 JO I1

-

--

----

_---

_.

-

~

-

I "

-I"DSITIDH I",,) I"DSIlIDH I.ID) S[CllQ'j _I"DS_{Il I}[»j I "" , I"DSITIDH I KID)

152.' 2.00 12 Ol.' 5.67 lil .0 2.38 13 457.2 6.00 203.2 2.67 J4 482.6 6.33 228.6 300 J5 50 •.• 6.63 2'504.0 3.33 16 533.4 7.00 Z7'3.' 3.67 J7 6011.0 7.98 304.' 4.00

I'

636.6 ' .35 133.4 4.38 It 5SII.1 1.65 355.6 4.67 10 58 •. 2

•

381.0 500 21 717.(, 9.42 406.4 5.33 Uc: 749.3 9.13

34 POSITION RADIAL SURVEY

-Fig, 12

CDlTDLIN: _PDSJTUIN

I"" )

,n

CP'IISITJC»f I ' PDSITIIIN (NI' rlD M.H O.ROI ti 13." 0.1771 STEP lllE: J/16' I • . 10 0.1000 Jt 11.70 0.1167

•

• . IS 0.4791 10 11." o 1163

• ..

.

0." 3

"

IJ. IJ 0.1 _

,

• . N 0.075 11 10.12 0.1 " I t i . ." 0.'167 a 1.13 O. I S '7 m.16 0._ 14 '.73 0.1146

•

• . se 0.1750 15 7." D.IDoU

• .

.

..

0 . • 42 11 7.14 0.0131 10 15.40 0.1333 r7 _'_._as 0 . .a3 • IPIIS'TlDI 17) 11 a .'J O.as25 11 1.16 0.07" I! Il.a 0.1917 111

..

.

..

O.~ STtP lllE: 1/32' 13

.,

.

..

0.1701 10

'

.

tl

O. ClS21

..

".CIS 0.1aIO tI

.

..

0.0417 15 17.46 0.1212 R I .• 0.0313 16 11 .• 0."" 13 .. ft D.oeoe 17 14.29 0.1'75 a4 0.79 0.0104

Loeations of wall statie pressure taps and radial

positions

of

in-stream pressure probe at the

same loeations,

(41)

0.375 DIA. 0250DI~. Pipe Axfs

J

.

c

B

IO-32UNF 2B-TAP 0.350 DEEP 0.0465 (US)

(42)

- - I H 11

-:][1

'

323- I

-td-Electric Isolator Electric Isolator Rake 1-4 1.77 (45) ~ (0..00..0.42) Gauge 19 1. 0.0.0.27

,

-Rake I.. 0.75 ~I

r

3°-7°

(43)

, - - - -- - - -<l: ë5 E E rt') rt')

Li635mm-i.-+I ..

- - - 2 5 . 4

mm

1 '

.

I;::-~':I Silve, Solde,

I

(a )

Straight 2-section Pitot Probe.

<l: o E E r--I.D

~I~

I

t

25O~---~---~---~---~---. 2 0 0 ··· .. ··

Boundary Layer

co

Pitot Probe

Cl-

"

i

150 ····

· ----···

·

· ··

· 1-···

· .

.

...

~

-j--

....

.

-.-

..

...

.

...

;

.. .

~

1 00---+----

· ----1---

-

---+-·----···1···-·-··

· -

..

...

--Ö

i :

Straight 2-Section

~

!

:

Pitot Probe

50 .

. -.

--_

...

--

...

-

... -

..

-

...

-

....

t·o.···

·

· ··

·

· ··

···

..

· .. ···-·· .. ·-·

..

···t···-L...----..,.---J , i O~----~-~---,'----~----~r----~

0.00

0.01

0.02

0.03

0.04

0.05 Time (s)

(44)

I--...-!

1---1---

L ---~ Nolr: I L 0.42 1.10 0.62 Uil 0.14 2..22

Malerlal: Staw.. Steel

0.0151 DIA. ~I+--+--++

(4 Hol . . I

(20 tI

( 0 )

Sho\rp

'

=:;:;~~~:=2=

\ .,.

jGou9t

16 (0.0 00651

.

99=(?O=

.

II_!I~~~~~~~~~~:·L

\ (I.O. 0.(41)

-==1=-~ , I 1-0.51 .. (945.-) ... _ - - - 1.04 (26400 .. " 1 - - _ ... - - - - 1.511

(55"""1~

Noer. • • ! 7'0" • • ! 90"

Malfttal: Stalna 9lwI

~O689(11_) HorlzOft101 llM 2.2II(~.-1

\

{'"

\GcN9lI9(î&~) f . - O.42

-,-Q2!8 " Not r- • • 120" 3

•• t,.,.

Hole 2 Hole •• uo· 2Ho1e Malfttal: ~ 5tftI

-1.4' ( 511 ,,",,)

~~

lil (U·O Sc:oIe 10·1 (c)

QOI3101A~~

(2 HoIeII ' -T (b)

,

1311 (35",,,,) 0:984(25 ... 1 0115(21_1:::1 1--1 îo~om

.

/

---

-L~ , -1.!..OO~

+-

1'-

~1i

....

(45)

M, I~O _{35 I} _I _I _II.JI_I_5.0 Exp.~ 30-+ 'l 25~--- ~

J

20~

·---l

%.00 M Exp.~77

301--1.

I 'l25

-~ ! 20 .

-J

15

-IlO

----

.

5+-1 %1 ' < ' .00 ----~-;,1tl1~1----·---·-·-r-·--·-- -I I i 0.01 0.02 0.03 0.04 Time (a) (a )

i

n~

4.0 1.0 +-0.0 0.06 i

I1

v.v , 4.0 C

..

3.0 :k !

~O

J

I

1.0 Exp.~70 1

I

3O-+

---t-

--

&;;.7f

·

";"'re

r

i

4.0

~

. I ...

r .

'l 25-j--- + ~ ~ 20~

---J

1

s+-l---·-f--i-F-~Trnl1-.1 ? 3.0 :g. 1.0 o I L . r I

I

:

0

b..

0 Lo·o 0.00 0.01 0.02 0.03 . . TiII'MI(a) ( b) 36IExp.~8

(

16.0 4.0 1 _€: ... 25 - -- _I Cl.

..

~

_I

I 3.0 ~ ! 20 _~

!

15 SIaIic

"'-u!e

~o

1 I

i

1.0 ;f~' 6 _{·10 ( ... )} i i 0.01 0.02 i 0.04 0.O!r·0 %.00 0.03 Time (a) (c ) .0 0.02 0.03 0.04 O. Ti/TIe (a) (d )

(46)

~I I~ Exp.3-aIO 30+ I I I I--4.0 'l 25+ l + t C _? ~ ! 2O~

-J

15-1-- III-r 3.0 :g, ! :>

1

2.0

I

J

1.0 ---t---. I I " . : i i

I

I .0 ~.oo 0.01 0.02 0.03 0.04 O.!ie 5-1 I /~. Time (a) (e ) ~I I~ 30 4.0 ;--"l25 ~ 3.0

l

! 20

I

Q. ! C"

--1

~

/

12.0 J

llo

j

5 - V '

t

~ 1 1 . 0 .--Ir-~ ::tlb.;;;;rnnr_' %.00 Time (a) (g ) ~ I I eI 15.0 Exp.~l 30+---1-. _i i 4.0 'l 25 - - - - --- -:!:...·-..

-t-..

..

~ ~ ! 20 --- . 3.0 :g, :> !

115 -

'

i

I

~~

.z

10

i

~·10(..,.)

-T-

----I I ~~oo 0.02 0.03 0.04 Time (a)

(f)

1.0 -t-O.O 0.06 35 I 15.0 Exp.3-084 30~ .. · -l 25 --- I - - ' - - - (:

i ,.

-

--

~---t-

3.0

~

15 .... - -

I

1 ~~ Jl 10 ---,-

J

5-+ 1

l

J'" • ~ ~ 11.0 9IIdic:JSarreI-10 ("'*) o I I " , - I I I 10.0 0.00 0.01 0.02 0.03 Time (a) ( h)

Fig.

17. Cont'd.

(47)

r---

---

----

---

-/

(48)

A B

c

4.0~---~~---~---~---~~----~

m

3.0

Cl.. ~

-

CD

-:J ~ 2.0 ···

e

Cl..

o

10

-Cl)

1 .

0

···I···_··· .. ···~·· ... ; ... , ... ., .. O.O~---~---~---~~---~---~

An experimental study of hypersonic flow development in a pipe

TECHNISC

HE U UV=:R

SITEIT DELfT