reference frame velocity的意思|示意

The velocity of the center of mass has not changed as seen from your frame of reference, because the velocity of center of mass is always the same, remember, because momentum is conserved.

质量重心的速度，并没有发生改变，你在参照系中可以看出，因为质量重心的速度，总是保持不变，要记住，由于动量守恒。

The velocity is with respect to a fixed frame of reference.

此速度是相对于固定标架的。

Mechanics Kinematics: trajectories, velocity, acceleration, motion of rigid bodies, change of reference frame.

力学运动：轨迹、速度、加速度、运动、刚体动力学变化的参考帧。

The moving reference frame is used in the impeller region and the boundary conditions are velocity inlet and pressure outlet.

在计算时对于叶轮区域采用旋转参考系的方式，边界条件分别是进口速度边界条件以及出口压力边界条件。