大流量三叶罗茨风机的全绝热效率及温度特性分析

Analysis of Full Insulating Efficiency and Temperature Character of Three Leaves Roots Blowers with Large Flow

介绍了大流量三叶罗茨风机的容积效率、机械效率、理想罗茨的绝热效率和全绝热效率ηad,对风机的无逆流冷却和有逆流冷却的两种温度变化情况进行了比较分析.结合生产实例说明,罗茨风机容积效率随径距比的变化,罗茨风机理想罗茨的绝热效率、全绝热效率ηad随风机的压力ε比增加呈现的下降趋势,排气温度随压力比ε增加呈现的上升趋势规律.大流量三叶罗茨风机采用逆流冷却极大地降低排气温度、减小回流冲击噪声.

Volume efficiency, mechanical efficiency, insulating efficiency ηad of ideal Roots and full insulating efficiency of three leaves Roots blowers with large flow are researched in this paper. Two cooling status are compared between non - reversed current cooling Roots blowers and Roots blowers with reversed current cooling. By citing examples in practice,the relationship between volume efficiency and radius - center distance ratio is discussed. Those status are illustrated （insulating efficiency of ideal Roots, full insulating efficiency ηad of three leaves Roots blowers is decreased as pressure ratio insreasing. Exhaust temperature is insreased as pressure ratio ε decreasing）. Exhaust temperature is decreased and back - flow impact and noise are reduced greatly for three leaves Roots blowers with large flow using reversed current cooling.