1、CHARACTERISTICS OF COUPLED NONGRAY RADIATING GAS FLOWS WITH ABLATION PRODUCT EFFECTS ABOUT BLUNT BODIES DURING PLANETARY ENTRIES (NASA-TN-X-72078) CHARACTERISTICS OF N75- 1097 1 COUPLED NONGRAY RADIATING GAS FLOWS UITH ABLATION PRODUCT EFFECTS FABOUT BLUNT BODIES DURING PLANETARY ENTRIES Ph.D. Uncla
2、s Thesis - (NASA)_ 181 p HC $7.00 CSCL 22C _ G3/13 02328 by KENNETH SUTTON A thesis submitted to the Graduate Faculty of North Carolina State University at Raleigh in partial fulfillment of the requirements for the degree of Doctor of Philosophy DEPARTMENT OF MECHANICAL AND AEROSPACE ENGINEERING RAL
3、EIGH 1973 APPROVED BY: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-SUTTON, KENNETH. Characteristics of Coupled Nongray Radiating Gas Flows with Ablation Product Effects about Blunt Bodies during Planetary En- tries. (Under the direction of FREDER
4、ICK OTTO SMETANA). A computational method is developed for the fully-coupled solution of nongray, radiating gas flows with ablation product effects about blunt bodies during planetary entries. The treatment of radiation ac- counts for molecular band, continuum, and atomic line transitions with a det
5、ailed frequency dependence of the absorption coefficient. The ablation of the entry body is solved as part of the solution for a steady-state ablation process. Application of the developed method is shown by results at typical conditions for unmanned, scientific probes during entry to Venus. The rad
6、iative heating rates along the downstream region of the body can, under certain conditions, exceed the stagnation point value. The ra- diative heating to the body is attenuated in the boundary layer at the downstream region of the body as well as at the stagnation point of the body. Results from a s
7、tudy of the radiating, inviscid flow about spheri- cally-capped, conical bodies during planetary entries are presented and show that the nondimensional, radiative heating distributions are nonsimilar with entry conditions. Therefore, extreme caution should be exercised in attempting to extrapolate r
8、esults from known distributions to other entry conditions for which solutions have not yet been obtained. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-BIOGRAPHY Kenneth Sutton was . He was reared in Jacksonville, Florida and graduated from Andrew
9、Jackson High School in 1957. He attended Jacksonville University for two years before transferring to the University of Florida where he received the degree of Bachelor of Mechanical Engineering in 1962. After graduating, he accepted a position with the Langley Research Center of the National Aerona
10、utics and Space Administration in Hampton, Virginia. He received his graduate education through the NASA Graduate Study Program. In 1963 he returned to the University of Florida and received the degree of Master of Engineering in 1964. He began night studies in 1964 with the Tidewater Extension Cent
11、er of George Washington University and received the degree of Master of Science in Governmental Administration in 1967. He entered North Carolina State University at Raleigh in 1968 to begin advanced studies in the Department of Vechan- ical and Aerospace Engineering. He returned to the Langley Rese
12、arch Center in 1969 where he performed the analysis presented in this thesls. He is presently assigned to the Advanced Entry Analysis Branch of the Spacecraft Systems Division at the Langley Research Center. He is a member of the American Institute of Aeronautics and Astronautics and the American So
13、ciety of Mechanical Engineers. He is registered as a Professional Engineer by the State of Florida. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-ACKNOWLEDGEMENTS The author wishes to express his appreciation to the National Aeronautics and Space A
14、dministration for its continued support of his graduate studies and for supporting the research presented in the thesis. The author wishes to thank the members of his advisory committee for their help and cooperation. He is especially grateful to Dr. Frederick 0. Smetana for his assistance and patie
15、nce during the authors studies and research investigation. Special appreciation is extended to Mr. Gerald D. Walberg of the Langley Research Center for proposing the topic of the research inves- tigation, for his continued support of the investigation, and for his consultation on many technical matt
16、ers. The author is appreciative of the technical consultation given to him by members of the Langley Research Center: Dr. Walter B. Olstad, Mr. Linwood B. Callis, Dr. Robert E. Boughner, Mr. Ralph A. Falanga, Mr. John T. Suttles, and Dr. G. Louis Smith. Also, the author is grateful for the technical
17、 assistance by members of the Aerothem Corporation: Mr. William E. Nicolet, Dr. Robert M. Kendall, and Mr. Eugene P. Bartlett. The author is grateful for the pleasant conversation, encourage- ment, and technical assistance extended to him by his office colleagues, Mr. Randolph A. Graves, Jr., and Mr
18、. E. Vincent Zoby. Special gratitude is expressed to Mr. Bennie W. Cocke, Jr. of the Langley Research Center for his guidance and help in the authors earlier career. Also, Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-appreciation is extended to Mr
19、. James H. Godwin of Langley Research Center for his assistance and friendship during the many nights the author spent at the computer complex. The authors graduate study was made easier by the work of Mr. Dick Cole and Mr. John Witherspoon of the Langley Research Center and Miss Eleanor Bridgers of
20、 North Carolina State University in efficiently handling the necessary administrative arrangements during his enrollment at North Carolina State University. The author wishes to express his appreciation to Miss Mary Anne Monaco for her editorial assistance and typing the original draft of the thesis
21、. Gratitude is also expressed to Mr. Charles R. Pruitt of the Langley Research Center for handling the final preparation of the thesis. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Page LIST OF TABLES vi LIST OF FIGURES vii LIST OF SYMBOLS xi INTR
22、ODUCTION . 1 REVIEW OF LITERATURE . 6 Radiation Transport Modeling 7 Radiating Flow Fields 11 Flow at Stagnation Region 11 Flow about Blunt Bodies . 14 Thermal Analyses for Venusian Entry 19 METHOD OF ANALYSIS 24 Radiating. Inviscid Flow Field Solution 28 Boundary Layer Solution 42 Radiative Transpo
23、rt Solution 51 RESULTS AND DISCUSSION 58 Non.Radiating. Inviscid Air Solution 59 . Radiating Inviscid Solutions about Blunt Bodies 60 Fully.Coupled. StagnatiowPoint. Solutions for Earth Reentry . . 68 . Fully-Coupled Solutions for Venusian Entry 70 SUMMARY AND CONCLUSIONS 78 EXTENSION OF PRESENT RES
24、EARCH . 80 LIST OF REFERENCES 129 . APPENDIX A Unsteady Characteristics Solution 137 APPENDIX B . Stagnation-Point Solution for Radiating. Inviscid FlowField . 141 APPENDIX C . Computer Program for Radiating. Inviscid Flow Field Solution . 144 Provided by IHSNot for ResaleNo reproduction or networki
25、ng permitted without license from IHS-,-,-LIST OF TABLES Page i Stagnation-point, radiative heating rates for air entry . . . 81 TI. Results from fully-coupled, stagnation-point solutions with mass injection for air entries . . . . . . . . . . . . 82 Provided by IHSNot for ResaleNo reproduction or n
26、etworking permitted without license from IHS-,-,-LIST OF FIGURES Page 1. Illustration of the mating of the boundary layer solution to the inviscid layer solution . . . . . . . . . . . . . . . . . 83 2. Calculation procedure for the fully-coupled, radiating flow field solution . . . . . . . . . . . .
27、 . . . . . . . . . . . 84 3. Flow field coordinate system for axisynunetric blunt body . . . 85 4. Schematic of use of unsteady characteristics at shock wave . . 86 5. Nonradiating, inviscid flow solution around a blunt body. Present method is compared with the method of Inouye et al. (ref. 88) . .
28、. . . . . . . . . . . . . . . . . . . . 87 - (a) Free-stream conditions and body shape . . . . . . . . . 87 (b) Shock shape at forward region of body and sonic line location . . . . . . . . . . . . . . . . . . . . 88 (c) Shock shape at downstream region of body . . . . . . . . 89 (d) Shock stand-off
29、 distance around body . . . . . . . . . . 90 (el Velocity distribution along body . . . . . . . . . . . . 91 (f) Pressure distribution along body . . . . . . . . . . . . 92 6. Radiating, inviscid flow solution about a blunt body during Earth reentry. Present method is compared with the method of Cal
30、lis (ref. 3) . . . . . . . . . . . . . . . . . . . . . 93 (a) Free-stream conditions and body shape . . . . . . . . . 93 (b) Pressure distribution along body . . . . . . . . . . . . 94 (c) Shock stand-off distance around body . . . . . . . . . . 94 (d) Radiative heating along body . . . . . . . . .
31、. . . . . 95 (e) Radiative heating along body. Callis results modified 96 7. Stagnation-point, radiative heating rates in an air atmo- sphere as a function of nose radius. Present results are compared with the method of Callis (ref. 7) . . . . . . . . . 97 Provided by IHSNot for ResaleNo reproductio
32、n or networking permitted without license from IHS-,-,-viii Page 8. Radiative heating distribution for free-stream conditions and body shape given in Figure 6(a) except Rn=2.0t m. Present results are compared with the method of . Callis(ref.3) 98 9. Radiative heating distributions along a sphericall
33、y-capped, conical body from radiating, inviscid flow solutions for entries in different atmospheres and different free-stream . conditions 99 10. A comparison of the stagnation-point, radiative heating rates for entries in air and in a .90 C02 - .10 N2 (by volume) gasmixture . 100 11. The distributi
34、on of radiative heating along spherically- capped, conical bodies for entry in air . 101 12. The distribution of radiative heating along spherically- capped, conical bodies for entry in a .90 CO - .10 N2 2 (by volume) gas mixture . 102 - 3 (b) V_=11.175 km/s ; pm=2.850 x 10 kg/m3 ; pa=117.3 N/m 2 h
35、=-8.43 M/kg ; Rn=.3048 m 102 m 13. The effect of nose radius on the distribution of radiative heating along a spherically-capped, conical body for entry in air 103 14. The effect of nose radius on the distribution of radiative heating along a spherically-capped, conical body for entry in a .90 C02 -
36、 .10 N (by volume) gas mixture 104 2 (a) Va= 8.740 km/s ; pa=3. 294 x kg/m3 ; p_=130.6 N/m 2 . hm=-8.43 w/kg ; -60“ Y. 104 (b) V_=11.175 km/s ; p_=2.850 x kg/m3 ; 2117.3 N/m 2 0 ha=-8.43 MJ/kg ; BC=60 105 15. Stagnation-point, radiative heating rates in C02 - N2 gas mixtures. Rn=.3048 m 106 -3 3 (a)
37、 Va=12.0 km/s ; pm=2.99 x 10 kg/m 106 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Page 16. Fully-coupled, stagnation-point solution for Earth reentry. Present method is compared with the method of Garrett (ref. 19) . . . . . . . . . . . . . . . .
38、 . . . . . . 107 (a) Free-stream conditions and specified wall conditions . . 107 (b) Temperature profile through layer . . . . . . . . . . . 108 (c) Radiative heating profile through layer . . . . . . . . 109 (d) Spectral distribution of radiative heating toward the body due to continuum processes
39、. . . . . . . . . . . 110 (e) Spectral distribution of radiative heating toward the body due to line processes . . . . . . . . . . . . . . 111 17. Trajectories for large and small probes during entry to Venus . . . . . . . . . . . . . . . . . . . . . . . . . . 112 18. Stagnation-point, radiative hea
40、ting rates along entry trajec- tories for large and small probes. Results from radiating, inviscid flow solutions . . . . . . . . . . . . . . . . . . 113 19. Fully-coupled, radiating flow solution with steady-state ablation of carbon-phenolic heatshield for large probe . . . 114 (a) Free-stream cond
41、itions and body shape . . . . . . . . . 114 (b) Comparison of radiative heating . . . . . . . . . . . . 114 (c) Radiative and convective heating distribution . . . . . 115 (d) Ablation rate distribution . . . . . . . . . . . . . . . 115 (e) Aerodynamic shear distribution . . . . . . . . . . . . . 11
42、6 (f) Momentum thickness Reynolds number distribution . . . . 116 (g) Spectral distribution of radiative heating toward the body due to continuum processes . . . . . . . . . . . 117 20. Fully-coupled, radiating flow solution with steady-state ablation of carbon-phenolic heatshield for small probe .
43、. . 118 (a) Free-stream conditions and body shape . . . . . . . . . 118 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-Page (b) Comparison of radiative heating 118 (c) Radiative and convective heating distribution . 119 . (d) Ablation rate distribut
44、ion 119 (e) Aerodynamic shear distribution . 120 f Momentum thickness Reynolds number distribution 120 (g) Spectral distribution of radiative heating toward the . body due to continuum processes 121 21 . Comparison between a turbulent and laminar boundary layer for fully-coupled solution for large p
45、robe . 122 (a) Heating rate distribution . 122 (b) Ablation rate distribution . 122 (c) Aerodynamic shear distribution . 123 (d) Spectral distribution at the wall of radiative heating toward the body due to continuum processes 123 22 . Fully.coupled. radiating flow solution with steady-state ablatio
46、n of carbon-phenolic heatshield for high velocity entry . 124 (a) Free-stream conditions and body shape . 124 (b) Comparison of radiative heating 124 (c) Radiative and convective heating distribution . 125 (d) Ablation rate distribution . 125 (e) Aerodynamic shear distribution . 126 (f) Momentum thi
47、ckness Reynolds number distribution 126 (g) Spectral distribution of radiative heating toward the body due to continuum processes . 127 (h) Spectral distribution of radiative heating toward the body due to line processes 128 Provided by IHSNot for ResaleNo reproduction or networking permitted withou
48、t license from IHS-,-,-LIST OF SYMBOLS D - 11 D parameter defined by eq. 21 sonic velocity, see eq. 49 parameter defined by eq. 22 Planck function parameter defined by eq. 23 parameter defined by eq. A4 parameter defined by eq. A5 or eq. 35 parameter defined by eq. A6 or eq. 36 specific heat specific heat parameter defined by eq. 61 parameter defined by eq. 24 binary diffusion coefficient for it11 and jth chemical species self-diffusion coefficient of a reference species parameter defined by eq. 25 exponential integral of order n exponential integral of order 3 div
