The expressions of the governing equations of turbulent flow with contravariant physical velocity components in a general non orthogonal curvilinear coordinate system are derived by means of tensor theory.A numerical method and a computer program for turbulent recirculating flow in the general non orthogonal curvilinear coordinate system are developed.Since the velocity and the displacement vectors are decomposed into their contravariant components,the method has the main advantages of its obviousness in physical meanings,easiness in treatment of boundary conditions and the suitability to the numerical calculations of turbulent flow in various complex geometries.The flow fields in some kinds of complex geometries are calculated.
According to the implicit numerical integration method proposed by Tyson.J,an improved computer program for pseudo one dimensional flow of combustion kinetics is developed with the aid of a chemical kinectic model with 12 species and 31 reaction.Variations of temperature,prssure,Mach number and mass fraction of chemical species in a supersonic combustion model are studied in detail.The results of scramjet combustor conditions corresponding to flight Mach numbers 6,10 and 15 show that chemical reaction rates decrease at rather low temperature and pressure at a combustor inlet and there is not enough time to ignite the mixture gas in the combustor at very high Mach number,in result the performance limits of scramjet kinetic combustion occur.
A new approach to evaluate the particle sizes and positions has been deve loped on the basis of their coherent images.According to the experimental and calculated results about the coherent images of steady particles,the paper described the features of coherent images of particles.It is concluded that the characteristics of the coherent images are different from those in incoherent cases,and the more the image deviates from the focus,the more obvious the differences are.From theoretical analysis, the conclusion has been drawn and proved that the normalized intensity distributions of coherent images of particles are the same when their recording far-field conditions are identical.The new method to determine the particle sizes and positions is just based on this conclusion.
