symmetrical flow

Compared with diode uncontrollable rectifier and phased thyristor rectifier, PWM rectifier has the advantage of symmetrical sinusoidal AC current, unity power factor operation and two-way flow of energy.

与二极管不可控整流或相控晶闸管整流器相比，PWM整流器具有网侧电流对称正弦、单位功率因数运行、能量能够双向流动的优点。

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It is also found that the critical Rayleigh number Rac changes with slot widths, and there exists symmetrical and unsymmetrical oscillation for the oscillatory flow and heat transfer.

数值实验还表明，流动和换热出现振荡时的临界Rayleigh数Rac与开缝圆的开缝度有关，且流动和换热的振荡会出现对称振荡和非对称振荡两种情形。

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Regarding asphalt pavement as an axial symmetrical body of multilayered saturation elastic half space, the fundamental thermal Biot consolidation theory and seepage flow equations are introduced.

将沥青路面视为多层饱和弹性半空间轴对称体，引入比奥渗流固结理论和渗流方程。

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