Cold acoustic tests have been performed to elucidate the effect of baffle on the damping characteristics of the first-tangential acoustic mode in a liquid rocket engine.Different kinds of baffle parameters were researched by acoustic tests.The results agree well with the theory typical example and show that when increasing the axial baffle length and the radial baffle number
the acoustic frequency of the first-tangential acoustic mode decreases and the acoustic damping capacity increases.Injector-forming baffles have some advantages over the typical straight baffles in acoustic damping capability;an optimal acoustic damping capacitance has been achieved in 0.1~0.4mm;axial baffle length can be reduced by using the optimal baffle gap
providing a possible solution of thermal cooling problems.