2.什么时候需要用惯性质量块?在什么频率下用惯性质量块变得很重要?

模态激振器相关问题

Many times it is difficult to support a shaker from a floor-mounted fixture, such as the Model 2050A lateral excitation stand shown below. In these cases, the shakers may be hung from a support cable attached above the test article. Often masses are attached to the base of the shaker trunnion to provide more inertia to push against for improved performance, typically this only an issue at very low frequency in the sub-10 Hz range.

很多时候,激振器很难从一个地面安装的夹具上进行支撑。例如下面图3所示的2050A型横向激励支架。这些情况下,激振器可能需要用一根支撑缆绳悬挂起来,缆绳连接到试件的上方。有时为了提高性能,质量块连接到激振器耳轴基座上,来提供更大的反推惯量,通常,在10Hz以下的很低频范围内,这才是个问题。

KSI-modal shaker FAQs-Fig3

图3 – 典型的激振器激励设置