A Study on the Numerical Modeling and Experimental Validation of a Low-Temperature Gas Generator

The low-temperature gas generator plays a critical role in suppressing pre-combustion reaction intensity in gas-solid two-phase flow by regulating gas temperature, thereby significantly enhancing detonation combustion performance. To systematically investigate its internal flow characteristics and cooling mechanisms, this study adopts an integrated approach combining numerical simulation and experimental validation. A coupled heat-transfer and flow simulation model for the internal flow field of the low-temperature gas generator is established based on the two-dimensional axisymmetric Reynolds-Averaged Navier-Stokes (RANS) equations for the gas phase, incorporating gas-solid heat and mass transfer models as well as a fuel addition model. Using this model, parametric numerical simulations are conducted for generator configurations with different flow channel profiles, lengths, and cross-sectional dimensions. By comparing the outlet gas temperatures across configurations, an optimal design with high cooling efficiency is identified. To validate the simulation results, experimental tests are carried out on the optimal configuration. Temperature variations before and after the gas flows through the solid fuel bed are monitored using a high-precision temperature measurement system. Experimental data demonstrate that the temperature reduction error remains within the expected range, confirming the engineering feasibility and technical effectiveness of the optimized cooling configuration.