摘要：Aim To put forward a type of math model for optimizing fan′s twisting *** This math model wu based on turbo-machinery Euler equations and calculus of variation, it was conducted for optimizing the aerodynamic parameters along the blade height of the fan, and the math method was produced for the optimization of fan's twisting law. Results The type 6102Q engine cooling fan was optimized by use of this model, and the calculation on data were contrasted with those of iso-reaction coefficiency flow type and free vortex flow type. Some probleme existing in long blade can be solved by use of above method. Conclusion The design parameters needn't be determined artificially, so calculating results are more rational to a high degree than that from other mehods.

摘要：Aim To raise the H-NE math model for designing engine *** Thismodel was founded on multi-nonlinear regression technology,and the quadratic equatingmethod was used to smooth original *** the sensitivity analysis about radiatoroptimization designing,some major restraints were *** Type 1301C radiator wasoptimizingly renwed by use o this model,and the new radiator is more excellent than theold one in respect of the heat transfer factor and the manufacturing *** Theradiation performance can be improved,the area can be reduced,and the fitting scope can bewidened if this model is used in designing radiators.

摘要：The primarily designed high speed rotary self cleaning air filter adopted axial outlet and tangential inlet, the filtering efficiency of the filter was relative low and couldn't reach the lowest efficiency limit. In order to enhance the filtering efficiency, the inlet and outlet structure of this new style of air filter were improved and the experimental research was carried out. The results showed that the filtering efficiency of the filter exceeded the lowest limit, this new style air filter can be practically developed further.

摘要：Aim To get the analytical for laminar viscous flow in the gap of two parallel rotating disks. Methods By estimating the order of magnitude of each term in the Navier-Stokes equations to drop small terms and achieve the required simplified differential equations, and by integrating the equations to obtain the solution for theflow between two rotary disks. Results Parameters related to the laminar viscous flow in the gap between two parallel rotary disks, such as the velocity, the pressure, the flowrate, the force, the shearing stress, the torque and the power derived. Conclusion The result provides a theoretical basis and an effective method for the designs of the devices connected with the laminar viscous flow in the gap between two parallel rotary disks.