Moonpools as a device for reducing pitch motion is investigated experimentally, numerically and by an approximate theory. A two-dimensional study is carried out of a rectangular body with two moonpools. Forced heave and pitch motion, as well as freely floating body in regular waves are studied. The body geometry is varied; two drafts and five different moonpool inlet configurations are considered; rounded and squared inlets, as well as vertical plates (appendages) extending below the inlet with three different depths. The outer corners of the body are square. There is a resonance as well as cancellation period in both pitch and heave, where the cancellation is the desired effect. By cancellation period we refer to a narrow period range where the pitch motion is nearly cancelled, due to the pressures induced by the moonpool piston-mode resonance. Our investigation reveals that the cases with rounded and square moonpool inlet geometries are most efficient in cancelling the pitch motions.

月池作为减少俯仰运动的装置已通过实验，数值和近似理论进行了研究。对具有两个月池的矩形物体进行了二维研究。研究了强制波动和俯仰运动以及规则波中的自由漂浮体。身体的几何形状是多种多样的。考虑了两个吃水和五个不同的月池入口配置；圆形和方形进气口，以及在进气口下方延伸的具有三个不同深度的垂直板（附件）。主体的外角为正方形。在音高和起伏上都有共振以及消除周期，其中消除是期望的效果。抵消期是指由于月池活塞模式共振引起的压力而使俯仰运动几乎抵消的狭窄周期范围。