对称圆弧加直线修正型线涡旋压缩机脱啮角与排气角研究

摘要

在采用对称圆弧加直线修正型线涡旋压缩机设计计算中,形成中心压缩腔时的转角与压缩机排气时主轴的转角完全不同.针对这两种情形下的主轴转角,由于没有完整而清晰的阐述,导致计算涡旋压缩机各压缩腔容积时容易产生较大误差.对此,通过研究采用对称圆弧加直线修正涡旋压缩机涡盘始端型线的几何特性,定义了脱啮角与实际排气角,阐明了二者之间相互区别,详细推导了脱啮角计算公式并分析了影响脱啮角的因素,且根据涡盘始端壁厚增加造成修正后中心压缩腔容积减少的本质特点,提供了修正后涡盘始端壁厚增加容积和实际排气角的计算方法.通过运算实例验证了脱啮角与实际排气角相差很大的结论,指出实际排气角将影响排气孔的设计.%In design and calculation of scroll compressor with symmetrical circular arc plus line-shaped top profile, rotating angle of crankshaft at the very moment when centre compression chamber is formed is totally different from that at the beginning of the discharge. There is no complete and distinct elaboration about the two kinds of angles yet, so it may cause large errors in calculating different compression chambers.Through in-depth research on the geometric property of scroll compressor with symmetrical circular arc plus line-shaped top profile, mesh-apart angle and discharge angle are defined and distinction between them is illustrated. According to the feature that reduction of centre compression chamber is due to an increase in wall thickness of top profile, the calculation formula of mesh-apart angle is derived elaborately and the methods to calculate the expanded volume of wall thickness of top profile and discharge angle after modification are presented. The difference between mesh-apart angle and discharge angle is verified through calculation example, it is mentioned that discharge angle of scroll compressor can make an impact on design of discharge port.