Lowspeed wind tunnel experiment requires strict of the wind speed, which requires a wild range of wind speed, high precision, and quick adjustment.
低速风洞实验要求对实验段的风速有严格的控制,要求风速调节范围宽,精度指标高,调节速度快。
2
The variable speed systems now used in crank presses have problems such as narrow in variable speed, fault in lowspeed and failure in tiny adjustment and so on.