Thermomechanical Stress-Strain State of Retention Compartment

A retention compartment is an isotropic cylindrical shell with load-bearing structures. When a rocket is launched, this structure is streamed by supersonic high-temperature exhaust gas flow. This generates the transient temperature field in the retention compartment. The transient stress-strain state of the retention compartment is generated by this temperature field. These stress states and the temperature fields of a retention compartment are analyzed. The objective of this research is the development of the general semiempirical approach for thermostress-state calculations of a retention compartment. It consists of several steps. At first, computations of fluid dynamics (CFD)-simulation of the exhaust gas is performed by using the commercial software Solid Works Flow Simulation. The local transient thermal boundary conditions for the retention compartment surface are obtained on the basis of the velocity, temperature, and pressure fields using the empirical criterion equations. Convective and radiant heat fluxes are accounted for in these boundary conditions. These boundary conditions permit one to calculate the transient temperature field. Then the stress-strain state with an account of elastoplastic deformations is analyzed. The finite-element method, which is implemented in the commercial software NASTRAN version 2014, is used to calculate the stress-strain state. The conclusions about the strength of the retention compartment are made.