1.热力学计算······································································12.动力计算········································································53.结构尺寸设计···································································184.参考文献········································································305.实践心得········································································3191．热力学计算已知条件有：相对湿度 φ空气等熵指数第一级吸气温度 Ts1=40℃第二级吸气温度 Ts2=40℃额定排气量 Qd=m3/min额定进气压力 Ps1=0.4MPa额定排气压力 Ps2=2 MPa压缩机转速取 n=1000r/min，活塞行程 S=2r=100mm。活塞杆长度 500mm，曲柄长度 r=50mm。行程容积，气缸直径计算① 初步确定各级名义压力根据工况的需要选择计数为两级，根据等压比的分配原则，但为使第一级有较高的容积系数，第一级的压力比取稍低值，各级名义压力级压力表如下：表 1-1级数ⅠⅡ吸气压力 ps0/MPa0.40.8排气压力 pd0/ MPa0.82压力比 ε0= pd0/ ps022.5② 定各级容积系数Ⅰ.确定各级容积系数。取绝热指数为 K=1.4,取各级相对余隙容积和膨胀指数如下：1=0.13 =1.3=1.35得：λv2741x(21/1.3-1)=0.92Ⅱ.选取压力系数：0.97 0.99 Ⅲ.选取温度系数：0.95 0.95 Ⅳ.选取泄露系数：0.92 Ⅴ.确定容积效率：得：80.74③ 确定析水系数第一级无水析出，故。而且各级进口温度下的饱和蒸汽压由文献查的t2=40℃ Psa=7375Pa得：=(4 105-0.8x7375)x2/(8x105-7375)8④ 确定各级行程容积=/(1000x0.78)077m3=×105×313×8）/（1000×8×105×313×0.74）04m3⑤ 确定气缸直径，行程和实际行程容积已知转速 n=1000r/min。取行程 s=100mm。得活塞平均速度： =sn/30=m/s由于汽缸为单作用，得：=(4Vs/πs)1/2=0.099m根据气缸直径标准，圆整的=100mm，实际行程容积为 077m3。活塞有效面积为 A’P115 m2同理得：D2= 0.05...
