中等Reynolds数平板绕流的动理论分析

郭永怀先生1953年给出的中等Reynolds数下、不可压缩流体有限长平板绕流的解析解是边界层理论中的经典工作.许多研究者对平板绕流阻力系数的郭永怀公式以及后续工作进行了 评估,评估的依据是Janour与Schaaf和Sherman的实验数据.本文的动理论分析和计算表 明: Schaaf和Sherman在低亚声速条件下(郭永怀先生1953年给出的中等Reynolds数下、不可压缩流体有限长平板绕流的解析解是边 界层理论中的经典工作. 许多研究者对平板绕流阻力系数的郭永怀公式以及后续工作进行了 评估, 评估的依据是Janour与Schaaf和Sherman的实验数据. 本文的动理论分析和计算表 明: Schaaf和Sherman在低亚声速条件下(郭永怀先生1953年给出的中等Reynolds数下、不可压缩流体有限长平板绕流的解析解是边 界层理论中的经典工作. 许多研究者对平板绕流阻力系数的郭永怀公式以及后续工作进行了 评估, 评估的依据是Janour与Schaaf和Sherman的实验数据. 本文的动理论分析和计算表 明: Schaaf和Sherman在低亚声速条件下(郭永怀先生1953年给出的中等Reynolds数下、不可压缩流体有限长平板绕流的解析解是边 界层理论中的经典工作. 许多研究者对平板绕流阻力系数的郭永怀公式以及后续工作进行了 评估, 评估的依据是Janour与Schaaf和Sherman的实验数据. 本文的动理论分析和计算表 明: Schaaf和Sherman在低亚声速条件下(郭永怀先生1953年给出的中等Reynolds数下、不可压缩流体有限长平板绕流的解析解是边界层理论中的经典工作.许多研究者对平板绕流阻力系数的郭水怀公式以及后续工作进行了评估,评估的依据是Janour与Schaaf和Sherman的实验数据.本文的动理论分析和计算表明:Schaaf和Sherman在低亚声速条件下(0.16相似文献   

CF-2沸石的表面酸性及催化性能

CF-2是一种新型的高硅沸石。1981年我们实验室首先在二乙醇胺-甘油-Na₂O-SiO₂-Al₂O₃-H₂O体系中制备成功^[1],以后才见到关于Theta-1^[2],ISI-1^[3],KZ-2^[4],NO-10^[5]和ZSM-22^[6]沸石的报道。     

20Ne+12C System and the Double-Alpha Transfer effect for a Deep Optical Potential

In this paper,the basic features exhibited by ²⁰Ne+¹²C system are analyzed and the excitation functions and the angular distributions of the ²⁰Ne+¹²C elastic scattering are well reproduced on the basis of the nuclear molecular orbital theory.The results show that the double-alpha transfer effect for a deep optical potential is responsible for the above difference in the elastic scattering excitation functions between these two systems.     

Vibrational Energy Transfer in CO+N2 Collisions: A Database for V–V and V–T/R Quantum-Classical Rate Coefficients

Knowledge of energy exchange rate constants in inelastic collisions is critically required for accurate characterization and simulation of several processes in gaseous environments, including planetary atmospheres, plasma, combustion, etc. Determination of these rate constants requires accurate potential energy surfaces (PESs) that describe in detail the full interaction region space and the use of collision dynamics methods capable of including the most relevant quantum effects. In this work, we produce an extensive collection of vibration-to-vibration (V–V) and vibration-to-translation/rotation (V–T/R) energy transfer rate coefficients for collisions between CO and N2 molecules using a mixed quantum-classical method and a recently introduced (A. Lombardi, F. Pirani, M. Bartolomei, C. Coletti, and A. Laganà, Frontiers in chemistry, 7, 309 (2019)) analytical PES, critically revised to improve its performance against ab initio and experimental data of different sources. The present database gives a good agreement with available experimental values of V–V rate coefficients and covers an unprecedented number of transitions and a wide range of temperatures. Furthermore, this is the first database of V–T/R rate coefficients for the title collisions. These processes are shown to often be the most probable ones at high temperatures and/or for highly excited molecules, such conditions being relevant in the modeling of hypersonic flows, plasma, and aerospace applications.