答：负压风机工作原理是：负压风机的主要工作原理是利用空气对流，达到通风换气的目的。风机运转后，利用风机的转动，将室内闷热的气体排出室内，将室外新鲜的空气吸入室内。在一定空间范围内，合理的安装风机，通风换气的效果可以达到90%以上，是一些大型场所，例如工厂车间厂房、各种大棚、养殖场以及其他大型场所理想的通风换气设备。

Q: what is the working principle of the negative pressure fan?

Answer: the working principle of the negative pressure fan is: the main working principle of the negative pressure fan is to use air convection to achieve the purpose of ventilation. After the fan is operated, the rotation of the fan is used to discharge the indoor hot gas and suck the outdoor fresh air into the room. Within a certain space, the reasonable installation of fans can achieve a ventilation effect of more than 90%. It is an ideal ventilation equipment for some large places, such as factory workshops, greenhouses, farms and other large places.