Study on the Thruster Plume Behaviors using Preconditioned Scheme and DSMC Method

예조건화 기법과 직접모사법을 이용한 추력기 플룸 거동에 관한 연구

  • Received : 2008.12.15
  • Accepted : 2009.07.01
  • Published : 2009.07.01

Abstract

To study the plume effects in the rarefied region, the Direct Simulation Monte Carlo(DSMC) method is usually adopted because the plume field usually contains the entire range of flow regime from the near-continuum in the vicinity of nozzle exit through transitional state to free molecular at far field region from the nozzle. The objective of this study is to investigate the behaviors of a small monopropellant thruster plume in the rarefied region numerically using DSMC method. To deduce accurate results efficiently, the preconditioned scheme is introduced to calculate continuum flow fields inside thruster to predict nozzle exit properties used for inlet conditions of DSMC method. By combining these two methods, the rarefied flow characteristics of plume such as strong nonequilibrium near nozzle exit, large back flow region, etc, can be investigated.

일반적으로 노즐 출구 부근에서 준연속체 상태로 방출된 추력기 플룸 유동은 노즐출구에서 멀어질수록 천이영역을 거쳐 자유분자 영역에 도달하기 때문에 희박영역에서의 추력기 플룸 영향을 연구하기 위해서는 광범위한 유동영역의 모델링이 가능한 직접모사법(DSMC)이 주로 사용된다. 본 논문에서는 희박영역에서 소형 단일추진제 추력기의 플룸 거동을 직접모사법을 이용해 수치적으로 예측하는 것이 목적이다. 정확한 결과를 효율적으로 유추하기 위해 예조건화 기법을 노즐 내부 연속체 영역의 해석에 도입하였으며, 이로부터 얻은 노즐 출구의 물성치 결과들을 직접모사법의 유입조건으로 적용하였다. 이렇게 두 기법을 결합하여 사용한 결과, 노즐 출구 부근에서 발생되는 강한 비평형성 및 넓은 후방 유동 영역 등과 같이 희박영역에서 플룸이 가지는 고유의 특성들을 확인할 수 있었다.

Keywords

References

  1. I. D. Boyd and J. P. W. Stark, "Modeling of a Small Hydrazine Thruster Plume in the Transition Flow Regime", Journal of Propulsion and Power, Vol. 6, No. 2, 1990, pp. 121-126. https://doi.org/10.2514/3.23232
  2. G. A. Bird, Molecular Gas Dynamics and the Direct Simulation of Gas Flows, Clarendon, Oxford, 1994.
  3. R. G. Wilmoth, G. J. LeBeau and A. B. Carlson, "DSMC Grid Methodologies for Computing Low-density, Hypersonic Flows about Reusable Launch Vehicles", AIAA Paper No. 96-1812, 1996.
  4. Q. Sun and I. D. Boyd, "A Direct Simulation Method for Subsonic, Microscale Gas Flows", Journal of Computational Physics, Vol. 179, No. 2, 2002, pp. 400-425. https://doi.org/10.1006/jcph.2002.7061
  5. I. D. Boyd, P. F. Penko, D. L. Meissner, and J. DeWitt, "Experimental Investigations of Low Density Nozzle and Plume Flows of Nitrogen", AIAA Journal, Vol. 30, No. 10, 1992, pp. 2453-2461. https://doi.org/10.2514/3.11247
  6. C. H. Chung, S. C. Kim, R. M. Stubbs, and K. J. DeWitt, "Low-Density Nozzle Flow by the Direct Simulation Monte Carlo and Continuum Methods", Journal of Propulsion and Power, Vol. 11, No. 1, 1995, pp. 64-70. https://doi.org/10.2514/3.23841
  7. P. V. Vashchenkov, A. N. Kudryavtsev, D. V. Khotyanovsky, and M. S. Ivanov, "DSMC and Navier-Stokes Study of Backflow for Nozzle Plumes Expanding into Vacuum", 24th International Symposium on Rarefied Gas Dynamics, Vol. 762, 2005, pp. 355-360.
  8. 송봉하, 김교순, 최윤호, 이병옥, "예조건화 기법을 이용한 층류 및 난류 화학반응 유동장 해석", 대한기계학회논문집 B권, 제30권, 제4호, 2006, pp.320-327
  9. C. L. Merkle and Y. H. Choi, "Computation of Low Speed Flows with Time Marching Procedures", International Journal for Numerical Methods in Engineering, Vol. 25, 1985, pp. 293-311.
  10. S. Venkateswaran, J. M. Weiss, C. L. Merkle and Y. H. Choi, "Propulsion-Related Flowfields Using the Preconditioned Navier-Stokes Equations", AIAA paper 92-3437, 1992.
  11. J. S. Shuen, K. H. Chen and Y. H. Choi, "A Time Accurate Algorithm for Chemical Non-Equilibrium Viscous Flows at All Speeds", AIAA paper 92-3639, 1992.
  12. 박재헌, 강신재, 김정수, 백승욱, 유명종, "인공위성 추력기 플룸의 DSMC 해석", 한국항공우주학회지, 제29권, 제8호, 2001, pp.111-118
  13. D. J. Kewley, "Predictions of the Exit Conditions, including Species Concentrations and the Ratio of, Specific Heats of Hydrazine Decomposition Thrusters", DFVLR, Internal Rept. IB 222-85 A05, Göttingen, Germany, 1985.
  14. R. F. Cuffel, L. H. Back and P. F. Massier, "Transonic Flowfield in a Supersonic Nozzle with Small Throat Radius of Curvature", AIAA Journal, Vol. 7, 1969, pp. 1364-1366. https://doi.org/10.2514/3.5349
  15. D. E. Rothe, "Electron-Bean Studies of Viscous Flow in a Supersonic Nozzle", AIAA Journal, Vol. 9, pp. 804-810, 1971. https://doi.org/10.2514/3.6279
  16. H. Legge, and G. Dettleff, "Pitot Pressure and Heat-Transfer Measurements in Hydrazine Thruster Plumes", Journal of Spacecraft and Rockets, Vol. 23, 1986, pp.357-362. https://doi.org/10.2514/3.25812
  17. B. B. Hamel, B. L. Maguire and E. P. Muntz, "Some Characteristics of Exhaust Plume Rarefaction", AIAA Journal, Vol. 8, 1970, pp.1651-1658.