根据高马赫数流场特征参数变化快、固态场特征参数变化慢的特性,编制开发了针对高速气流的"半解耦"显式流固耦合近似计算程序,并通过数值方法分析了该方法的计算误差,分析结果显示其能够较准确地模拟高速流场与固态场长时间非稳态耦合问题.在此基础上,运用"半解耦"流固耦合方法数值模拟了高速气流横掠缝隙-腔体典型密封结构的非稳态过程,并与相关实验测试数据进行了对比,验证了程序可靠性.随后,进一步分析了气流侵入密封结构的主要特性,总结了密封结构内、外流场中气流温度、压力和速度的分布特征以及其随时间的变化规律,研究了密封结构中加热板气动热流随时间的变化规律,探讨了密封结构中固体温度场分布特征及其随时间积累的变化规律等.最终,计算结果说明了密封体的结构布局对其内部热状况的决定性影响.
In view of the fact that the characteristic parameters of a high Mach flow field vary much faster than those of the solid field, a program of approximate numerical simulation of the semi-decomposd fluid and solid coupling is developed and compiled. The calculating error of the method is analyzed by numerical simulation, and the results show that this method can accurately simulate the fluid and solid coupling in a high speed airflow field during a long unsteady process. The process of a high speed airflow impacting the seal structure is simulated by this method and the program is proved to be feasible after a comparison of the calculated results with the related experimental test. And then the features of the airflow invading the seal structure are analyzed. The contours of the flow field temperature, pressure and velocity inside and outside the seal structure and the their variation during the course of an unsteady process are summarized. The variation of the aerodynamic heat flux of the heating board with time is analyzed. The rules of the temperature variation of the seal structure with time are investigated. Finally, the results show that the structural layout of the seal plays a decisive role in the seal structure's thermal conditions.
[1] Chuppb R E, Prior R J, Loewenthal R G, et al. Advanced seal development for large industrial gas turbines. AIAA-1997-2731, 1997.
[2] Paolillo R, Clouds D, de Jong F, et al. Advanced seal rig experiments and analysis. AIAA-2005-4150, 2005.
[3] Delgado I R, Proctor M P. Continued investigation of leakage and power loss test results for competing turbine engine seals. AIAA-2006-4754, 2006.
[4] Su H. Structural design, performance analysis and tests of finger seal. Xi'an: Northwestern Ploytechnical University, 2006.(in Chinese) 苏华. 指尖密封结构和性能的设计分析与试验研究. 西安:西北工业大学, 2006.
[5] Wang X. A theoretical and experimental study for hydrostatic finger seal. Harbin: Harbin Engineering University, 2006. (in Chinese) 王旭. 流体静压型指尖密封的理论与试验研究. 哈尔滨: 哈尔滨工程大学, 2006.
[6] Stein S, Thiokol M. Seal material selection, design and performance-advancements from the space shuttle booster redesign. AIAA-1989-2774, 1989.
[7] Edward L, Palko J. High temperature seal energizer device development. AIAA-2005-3370, 2005.
[8] Schfer M. Numerical simulation of coupled fluid-solid problems. Computer Methods in Applied Mechanics and Engineering, 2001, 190(28): 3645-3667.
[9] Geng X R, Zhang H X, Shen Q, et al. Study on an integrated algorithm for the flowfields of high speed vehicles and the heat transfer in solid structures. Acta Aerodynamics Sinica, 2002, 20(4): 422-427. (in Chinese) 耿湘人, 张涵信, 沈清, 等. 高速飞行器流场和固体结构温度场一体化计算新方法的初步研究. 空气动力学报, 2002, 20(4): 422-427.
[10] He L, Oldfield M L G. Unsteady conjugate heat transfer modeling. Journal of Turbomachinery, 2011, 133(3): 031022-031033.
[11] Wu Z N. Aerodynamics. Beijing: Tsinghua University Press, 2008. (in Chinese) 吴子牛. 空气动力学. 北京:清华大学出版社, 2008.
[12] Zhang Z C. Hypersonic aerodynamic heating and thermal protection. Beijing: National Defence Industry Press, 2003. (in Chinese) 张志成. 高超声速气动热和热防护. 北京: 国防工业出版社, 2003.
[13] Shen Q. Rarefied gas dynamics. Beijing: National Defence Industry Press, 2003. (in Chinese) 沈青. 稀薄气体动力学. 北京: 国防工业出版社, 2003.
[14] Chen X. Kinetic theory of gases and its applications to the studies of heat transfer and fluid flow. Beijing: Tsinghua University Press, 1996. (in Chinese) 陈熙. 动力论及其在传热与流动研究中的应用. 北京: 清华大学出版社, 1996.
[15] Yan J L, Wang Y Q. Engineering thermodynamics. Beijing: China Electric Power Press, 2004. (in Chinese) 严家禄, 王永青. 工程热力学. 北京: 中国电力出版社, 2004.
[16] Ma C F. Practical handbook thermophysical properties. Beijing: China Agricultural Machinery Press, 1986. (in Chinese) 马重芳. 实用热物理性质手册. 北京: 中国农业机械出版社, 1986.