The former causes forced vibration at the circular frequency of the crank shaft and the latter causes transient vibration at the natural frequency of the press. 慣性力激發(fā)的振動(dòng)是以曲軸轉速為頻率的強迫振動(dòng)，加工力激發(fā)的是以壓機固有頻率為頻率的過(guò)渡振動(dòng)。
In the regenerative liquid propellant gun,the coupling oscillation of the fluid sys-tem in the reservoir including free vibration and forced vibration may be formed. 在再生式液體發(fā)射藥火炮中，貯液室流體系統可能發(fā)生由自激振動(dòng)與強迫振動(dòng)構成的耦合振蕩，在噴射結束期很可能形成共振。
