foppl meaning in English

弗普尔

It is found that the couple of foppl vortex is unstable from the beginning when it engendered . the changing frequency is very slow at first , almost 2 . 5 % ~ 3 % of the frequency when it is stabled . the amplitude is also so limited at the beginning the maximum is only about 0 . 035 % ~ 0 . 05 % of the amplitude when it develops fully
) ppl涡对从产生的一瞬间就是不稳定的，其初始变化频率十分缓慢，初始变化频率大约是周期变化稳定以后变化频率的2 . 5 3左右；波动幅度也十分有限，其初始阶段最大值仅为周期性充分发展幅度的0 . 035 0 . 05左右。