Finite element analysis and optimization of multi-layer combined ultrahigh pressure cylinder
The finite element model was established by the finite element method of Workbench. The prestressed state and the working state of the multi-layer composite cylinder was used to calculate by the finite element method. The general distribution law of the stress of the multi-layer cylinder is obtained, and the equivalent stress distribution is not uniform. At the same time theoretically based on the elastic limit of multilayer composite cylinder unified solution, and the optimization condition is determined. The design of multi-layer ultrahigh pressure cylinder is optimized. The results show that the nonuniformity of the stress distribution of the cylinder can be improved greatly. The study can provide technical support for the structural design and optimization of the multi-layer ultrahigh pressure cylinder.
Stress analytical solution for an infinite plane containing two holes
Abstract An analytical solution is presented for an elastic infinite plate containing an ellipse hole and a circle hole, which undergoes the internal traction along the holes and uniform tensions and shears at infinity. The solution uses the conformal transformation in complex functions, with the multiple connected region mapping onto a circular ring. The stress distribution solved for the infinite plane containing two unequal circle holes in prior literatures is the special case of this article. And contrast between the results of two unequal circle holes obtained by using the present analytical method and the Hoang's results is made in the article. As there is no analytical solution for two non-circular holes, the results obtained using the present analytical method are compared with the numerical results calculated by ANSYS. Computational examples given in this article has been analyzed to study the effect of distance between two holes, the ratio of stress in two directions at infinity, and the ratio of the major and minor axis, on the stress distribution of the hole boundary.
Laminar heat or mass transfer in rectangular channels and in cylindrical tubes for fully developed flow: comparison of solutions obtained for various boundary conditions
Abstract A comparison is made of results obtained with various boundary conditions at the wall of the channels. By comparing blood Sherwood numbers for finite wall resistance with those for constant concentration boundary condition only a small variation is found for various points along the blood channel.