Abstract: Theoretical analysis is performed of the scaling of gas-gas cold flow fields and numerical studies made on the scaling of the flow fields in single-element chambers with gaseous oxygen and gaseous hydrogen. To obtain the scaling criterion of a gas-gas cold flow field, formulation analysis of the gaseous multi-component mixed flow 3D Navier-Stokes equations is conducted and dimensional analysis is also applied to the gas-gas mixing phenomena. The criterion indicates that the size and the testing back pressure of a gas-gas injector chamber can be changed. Based on the criterion, numerical simulations of full-scale and subscale single-element gas-gas injector chambers are studied in a total of three conditions. The results demonstrate that the flow field structures of similar geometry hardwares are similar at different testing back pressures.

Key words: scaling, similarity, cold flow, full flow stage combustion cycle, gas-gas mixing, numerical analysis