关键词: 冲压发动机；磁流体；发电通道；流场特性；数值模拟

Abstract: MHD power generation is an efficient way to solve the onboard power supplying problem of aircraft using ramjet engine. In order to study the inner flow field characteristics and energy conversion mechanism，focus on segmented Faraday MHD channel，integrate with experimental system`s design parameter，MHD five wave model in low magnetic Reynolds condition was established and second order entropy scheme was used to calculate it. By analyzing 4 different cases，the flow characteristics of segmented Faraday MHD channel under different experiment conditions were studied. The calculation results show that as the magnetic interaction parameter evolves from 0 to 0.1，MHD channel’s exit temperature rises by 10.4％ whereas the exit velocity decreases by 27.7％，Mach number decreases by 25％，when magnetic interaction parameter increases to 1，exit temperature increases by 20.8％. Energy conversion ratio becomes higher as well as the adverse pressure gradient on the inner wall of the channel，which will lead to a flow separation. When the load coefficient is 0.5，there is a bigger decrease in exit velocity，which reaches 11.7％ and Mach number decreases by 8％ comparing to that the load coefficient is 0.8. MHD channel will produce more joule heat，shows a higher energy conversion ratio but lower electrical efficiency. When MHD power generation experiment is implemented，increasing the magnetic interaction strength and choosing appropriate external load can improve the power generation performance of MHD channel.

Key words: Ramjet engine；MHD；Power generation channel；Flow field characteristics；Numerical simulation