Airbreathing Hypersonics Laboratory China Aerodynamics Research and Development Center Osculating Inward turning Cone Waverider/Inlet (OICWI) Design Analysis

Airbreathing Hypersonics Laboratory

China Aerodynamics Research and Development Center

Osculating Inward turning Cone Waverider/Inlet (OICWI) Design

Analysis and Experimental Study

1) Air-breathing Hypersonic Research Center CARDC Mianyang China 621000

2) Science and Technology on Scramjet Laboratory Hypervelocity Aerodynamics Institute CARDC Mianyang China 621000

Wu Yingchuan; He Xuzhao; Le Jialing



Contents

Introduction Basic inward turning cone flow field design

and analysis Design methods for Osculating Inward

turning Cone Waverider forebody Inlet Numerical analysis of the integrated OICWI’s

performance Experimental study for the integrated OICWI Conclusion



• Waverider has high lift to drag ratio, it is suitable to be air-breathing Hypersonic vehicle’s forebody or body.

• In engineering practice, several kinds of air breathing vehicles are using or partially using integrated wave rider forebody/inlet design methods

Japhar X-51A Blackswift



• In present paper, an waverider inlet integration design methods are put forward which is basing on osculation axisymmetric and stream line tracing theory. This design method is called Osculating Inward truing Cone Waverider Inlet design method. This method is conformed and verified by comparison of the OICWI’s design results and inviscid on design condition results. The viscous results on design condition and on off design conditions are also presented in this paper. The wind tunnel experimental studies on design and on off design condition are conducted which is Mach number 5,6, 7 and angel of attach -2,0,2,4,6 degree.



2. Basic inward turning cone flow field design and analysis

Fig1. Basic inward turning cone flow field structure

JB

Axisymmetric Axis

Center Body G

E'

H

F

O O'

Cowl Wall

Shock Cancel Region

I



Fig2. Inward turning cone Mach number contour by MOC design



Fig.3 Inward turnin cone flow field pressure contour comparison between MOC and CFD



X/Rs

P/P

0 0.5 1 1.5 2 2.5 30

2

4

6

8

10

12

14

CFD CenterbodyMOC CenterbodyMOC CowlCFD Cowl

8

Fig.4 Center body and cowl wall presure comparison between MOC and CFD results



3. Design methods for Osculating Inward turning Cone Waverider forebody

Inlet(OICWI)

The design method of integrated OIC waverider forebody inlet is developed from Osculating Inward turning Cone method. Combining Osculating axisymmetric method and streamline tracing technical, the OICWI design method uses OIC method and streamline tracing method to integrated waverider forebody inlet design. In the design procedure of OICWI, it has not geometrical modification and geometrical shape changing process.



Fig.5 Osculating methods sketch map in the OICWI cowl lip plane

ICC

FCT

A

B

C

D

E E′

D′

C′

B′

A′

Inlet Capture Area

(BB′CC′)

1. firstly we define inlet cone leading edge shock curve(Inlet Capture Curve) ICC.

2. The forebody inlet’s leading edge(front capture ratio FCT) use straight line add parabolic curve to generate.

3. Along the ICC curve, the ICC curve’s curve center is generated. For example, in the point B of ICC curve, the corresponding curve center A is generated. The point B in ICC curve and the curve center A generate the osculating plane AB.



B

Axisymmetric Axis

Center Body G

E

F

O O'

Cowl Wall

Streamline

A

E

D D

CX/Rs 100

Y/Rs100

100 200 300

50

100

150

200

250

300

350

X

X

Fig.6 OICWI streamline tracing methods in the Oculating plane AB

In the actual design, only a part of ICC curve(section BB′) act as inlet capture section, the corresponding inlet cowl leading edge capture area is BB′CC′. the inlet side wall surface is constructed by the corresponding osculating

plane. In fig5, they are BC and B′C′ line.



• Fig7 is an integrated OICWI which is designed by above described design method. The integrated waverider forebody inlet has a width of 0.3 meter. The waverider forebody’s length is 0.33 meter, and total length up to isolate exit plane is 0.68 meter. The inlet capture flow path width is 0.14 meter. The total compression ratio of this integrated OICWI is 4.47 and the inner compression ratio is 1.85.

Fig.7 3D view map o the designed OICWI



4. Numerical analysis of the integrated OICWI’s performance

The inviscid and viscous performance of the designed OICWI is simulated on design condition. The comparison is given for the inviscid numerical simulating result and the design result. For the design condition, the free stream flow is Mach number 6, to simulate the 25Km high atmosphere condition. The numerical simulation is using CFD software AHL3D, the inviscid flux construction method is third order MUSCL interpolation AUSMPW+ scheme. The turbulence model use two equation k-w TNT, using the wall function method to improve the simulation result accuracy. Total computational grid number is about 2 million.



Fig.9 Viscous Mach number and pressure contour in ICWI’s symmetry plane

Fig.8 Inviscid Mach number and pressure contour in OICWI’s symmetry plane



13.9

15.0 14.7

14.5

14.2

10.3

10.0

10.310.5

10.313.8

3.803.803.422.63

Z(m)

Y(m

)

-0.05 0 0.050.1

0.15

0.2

Flow field comparison in waverider-inlet exit plane

viscous P/P

viscous Mach number inviscid Mach number

inviscid P/P 88

Fig.10 Viscous and inviscid Mach number contour comparison in inlet cowl lip plane

Fig.11 viscous and inviscid Mach number and Pressure comparison in isolate exit

plane



Fig.12 3D view of integrated OICWI inviscid flow field structure

Fig.13 3D view of integrated OICWI viscous flow field structure



Table1 comparison of theory, inviscid and viscous result of OICWI’ on design condition

Table 1 is the Mach number, total pressure recovery, pressure rise ratio and mass flux capture ratio of theoretical design, inviscid simulation and viscid simulation results for the integrated waverider forebody inlet’s isolate exit plane. It shows that the theoretical design results and inviscid simulation results are fit with each other very well. For the OICWI’s flow field structure, the inviscid simulation and theoretical design results fit with each other well too. From those two points, we can see that present OICWI design method is correct.



5. Experimental study for the integrated OICWI

The experiment study is fulfilled in China aerodynamic research and development center’s 0.5m hypersonic wind tunnel. The experiment section has radios of 0.5m. Experimental mach number range is 4.9~11.7. The accuracy of the Mach number is 0.005. The simulation height range of this wind tunnel is 20km~48km.

CARDC Hypersonic wind tunnel



Fig14. the experimental study model of integrated waverider forebody inlet

Fig15 the unstart map for OICWI symmetry plane under 106 back pressure

ratios and free stream Mach number 5

Fig16. the self start map for OICWI symmetry plane when high pack pressure vanished



Fig 18. the wind tunnel experimental model for integratd OICWI



Ma5 AOA 4 Ma5 AOA 2

Ma5 AOA 0 Ma5 AOA -2

Fig19 flow field shadow graph map at free stream mach number 4.95, total pressure 0.74Mpa , total temperature 363K,AOA from 4 to -4 degree.



Fig20 flow field shadow graph map at free stream mach number 5.96, total pressure 1.44Mpa , total temperature 475K,AOA from 4 degree to -4 degree.

Ma6 AOA 4 Ma6 AOA 2




Fig21 flow field shadow graph map at free stream mach number 6.97, total pressure 3.02Mpa , total temperature 602K,AOA from 4 to -4 degree.

Ma7 AOA 4 Ma7 AOA 2




From the experimental shadow graph picture, the integrated OICWI can start smoothly from Mach number 5 to Mach number7, from AOA 4 degree to -4 degree. In the waverider forebody inlet’s flow field, there are 2 main shock waves. The first shock wave is the forebody compression shock wave, the second shock wave is the inlet cowl reflect shock wave. Those two shock waves have obviously three dimensional characteristics. In the Mach number 5 to Mach number 7 conditions, the shadow graphs show that the leading edge shock is very close to the inlet cowl leading edge. Those phenomena mean that OICWI has high mass flow capture ability and small mass flow spillage under non design conditions.



Fig22. Body side symmetry plane CFD and experimental pressure distribution comparison at

flow condition Mach number 5.96, AOA0 degree.

Fig 23 cowl side symmetry plane CFD and experimental pressure distribution comparison at

flow condition Mach number 5.96, AOA0 degree.

X(mm)

P/P

-600 -400 -200 02

12

22

32

42

CFD pressureEXP pressure

8

symmetry body wall

symmetry cowl wall

X(mm)

P/P

-600 -400 -200 02

12

22

32

42


8

symmetry body wall

symmetry cowl wall

The computation and experiment comparison studies are conduction under Mach number 5.96, total pressure P0=1.44Mpa, total temperature T0=475K, AOA=0 degree condition.



Fig24. width direction(from forebody leading edge ) pressure distribution comparison

between CFD and experimental data at mach number 5.96 AOA0.

Fig25 3D view of OICWI experimental model flow field structure at mach number 5.96 AOA0.

Z(mm)

P/P

-60 -40 -20 0 20 40 60

2

4

6

8

10


8



Fig 26 isolate exit mach number andpressure contour at Mach number 5.96, 0 angle of attack.



6. Conclusion An waverider forebody inlet integrated design method:

Osculating Inward turning Cone Waverider Inlet (OICWI) design methods are presented in present paper. The numerical and experimental studies are conducted for this kind of integrated waverider forebody inlet on design and off design conditions. From present studies, it shows that OICWI has some good characteristics such as:

1. The design methods for OICWI using streamline tracing and osculating inward cone technical, the design processes are according with aerodynamic principles.

2. The OICWI’s shape, inner compression ratio and isolate exit flow parameter can be easily adjusted through ICC and FCT curve, the design of an OICWI is flexible and easily.



3. From the comparison of inviscid simulation results on design condition and OICWI’s design results, they compare with each other well and the consistent results show that present OICWI design method is correct.

4. From the simulation and experimental studies result on design and off design conditions, it shows that OICWI has high pressure recovery, good flow parameter uniformity and good flow capture characteristics. It has small flow spillage in three dimensional design and off design conditions.

5. The experimental studies are performed in present studies, the experimental study results have good consistency with numerical simulation results, experimental and numerical simulation result are compared with each other well.



Thank you for your attention!

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Airbreathing Hypersonics Laboratory China Aerodynamics Research and Development Center Osculating Inward turning Cone Waverider/Inlet (OICWI) Design Analysis