两列二级二缸双作用无油润滑对称平衡型热力动力计算

活塞压缩机原理课程设计石油气压缩机设计公司：学员姓名：指导教师：日期：已知数据一、结构形式两列二级二缸双作用无油润滑对称平衡型二、工艺参数Ⅰ级名义吸气压力p1Ⅰ=0.01MPa(表压)吸气温度Ts1=18℃Ⅱ级名义排气压力p1Ⅱ=1.3MPa(表压)吸气温度Ts2=30℃排气量（Ⅰ级吸入状态）Vd=70m³/minⅡ级排气温度Td2≤140℃相对湿度φ=0.8三、结构参数活塞行程：S=2r=2x120=240mm电机转速：n=496r/min活塞杆直径：d=70mm电机：JB500-12型隔爆式异步电动机，500KW连接：电动机转子直接装在曲轴端（电机转子兼做飞轮）运动部件质量：名称Ⅰ级Ⅱ级活塞组件十字头组件连杆组件188.7689.0386.025162.6989.0386.025石油气组成成分石油气成分N2C1C2C3C4C5H2O体积/%(ri)1.07180.1544.4465.9123.1251.7073.584计算过程一、压力比确定一级吸气压力ps10.11MPa(a)，二级排气压力pd21.4MPa(a)总压力比ε=pd2/ps1=12.73压力比分配ε1=ε2=√ε=3.57二、压缩性系数一级吸气N2CH4C2H6C3H8C4H10C5H12Z1s1110.90.90.9吸气温度K291291291291291291吸气压力Mpa0.110.110.110.110.110.110.953406一级排气N2CH4C2H6C3H8C4H10C5H12Z1d1110.960.940.9排气温度K373.1691373.1691373.1691373.1691373.1691373.1691排气压力Mpa0.3924280.3924280.3924280.3924280.3924280.3924280.958203二级吸气一级排气N2CH4C2H6C3H8C4H10C5H12Z1d1110.90.90.9排气温度K303303303303303303排气压力Mpa0.3924280.3924280.3924280.3924280.3924280.3924280.953406二级排气N2CH4C2H6C3H8C4H10C5H12Z2d110.980.960.760.74排气温度K396.5906396.5906396.5906396.5906396.5906396.5906排气压力Mpa1.31.31.31.31.31.30.948958三、过程指数绝热指数KmN2CH4C2H6C3H8C4H10C5H12Vi1.071%80.154%4.446%5.912%3.125%1.707%k1.41.321.271.161.11.08Zm1=(𝑋𝑖𝑍𝑖)Zm4=(𝑋𝑖𝑍𝑖)Zm2=(𝑋𝑖𝑍𝑖)Zm3=(𝑋𝑖𝑍𝑖)Km=1.268n1=0.98xKm=1.243n2=Km=1.268四、各级排气温度排气温度Td=Tsε(n-1)/n一级排气温度Td1=291x3.57(1.243-1)/1.243=373.17K=100.17℃二级排气温度Td1=303x3.57(1.268-1)/1.268=396.59K=123.59℃五、各项系数1)容积系数λv=1-a(ε1/m-1)第一级相对余隙容积a1=0.1第二级相对余隙容积a2=0.12膨胀系数m=1+0.5(k-1)第一级膨胀系数m1=1+0.5(1.243-1)=1.134第二级膨胀系数m2=1+0.5(1.268-1)=1.166第一级容积系数λv1=1-0.1(3.57(1/1.134)-1)=0.79第二级容积系数λv2=1-0.12(3.57(1/1.166)-1)=0.752)压力系数一级二级进气相对压力损失δs10.03进气相对压力损失δs20.023排气相对压力损失δd10.07排气相对压力损失δd20.053666667相对压力损失δ01=δs1+δd10.1相对压力损失δ02=δs2+δd20.076666667压力系数λp=1-(1+a)Δpa/(n∙λv∙p1)进气压力损失Δpa=psδs第一级进气压力损失Δpa1=ps1δs1=0.11x0.03=0.0033第二级进气压力损失Δpa2=ps2δs2=0.39x0.03=0.009第一级压力系数λp1=1-(1+0.1)0.0033/(1.243x0.79x0.11)=0.97第二级压力系数λp2=1-(1+0.12)0.009/(1.268x0.75x0.39)=0.993)温度系数λt1=λt2=0.934)析水系数λφ=(𝑝1−𝜑𝑝𝑠1)𝑝2(𝑝2−𝑝𝑠2)𝑝1第一级进气温度下的饱和蒸汽压力ps1=0.0020644MPa第二级进气温度下的饱和蒸汽压力ps2=0.0042455Mpaλφ=(0.11−0.8𝑋0.0020644)0.39(0.39−0.009)0.11=1第二级排气温度下的饱和蒸汽压力ps3=0.21809Mpa，φps1ε=0.021Mpaps3，第二级排1𝐾𝑚−1=𝑉𝑖𝐾𝑖−1=3.59气处无水析出。5)泄漏系数λl泄漏系数λl第一级第二级气阀0.020.02活塞环0.0060.006填料0.0010.001λl=1/(1+∑v)0.9689922480.968992248六、气缸各参数1)气缸工作容积计算第一级气缸行程容积Vh1=Vd/(λv1∙λp1∙λt1∙λl1∙n)Vh1=70/(0.79x0.97x0.93x0.97x496)=0.204m³第二级气缸行程容积Vh2=𝑉𝑑𝑛𝑝𝑠1𝑝𝑑1𝑇𝑠2𝑇𝑠1λφλv2∙λp2∙λt2∙λl2Vh2=70×0.11×303×1496×3.57×291×0.75×0.99×0.93×0.97=0.061m³2)气缸直径计算气缸直径D=√(2Vh/πsz+d²/2)第一级气缸直径D1=√(2×0.204/3.14/0.24+0.07²/2)=0.7378m第二级气缸直径D2=√(2×0.061/3.14/0.24+0.07²/2)=0.4057m3)圆整气缸直径第一级气缸直径D’1=0.74m第二级气缸直径D’2=0.41m4)第一级缸径比ψ1=s/D1=0.24/0.74=0.324第二级缸径比ψ2=s/D2=0.24/0.41=0.585活塞平均速度vm=sn/30=0.24×496/30=3.968m/s七、复算压力比1)圆整后行程容积V'h1=sπ(2D’1²-d²)/4=0.24×3.14×(2×0.74²-0.07²)/4=0.206m³V'h2=sπ(2D’2²-d²)/4=0.24×3.14×(2×041²-0.07²)/4=0.062m³2)压力比复算第一级名义排气压力pd1=Vh1V'h2/(V'h1Vh2)pd1=0.204×0.062×3.57/0.206/0.061=0.398MPa第一级名义压力比ε1=pd1/ps1=0.398/0.11=3.62第二级名义压力比ε2=pd2/ps2=1.4/0.398=3.513)复算容积系数第一级容积系数λ’v1=1-0.1(3.62(1/1.13)-1)=0.7889第二级容积系数λ’v2=1-0.12(3.51(1/1.13)-1)=0.75674)复算气缸行程容积第一级气缸行程容积Vh1=Vd/(λv1∙λp1∙λt1∙λl1∙n)V’h1=70/(0.7889x0.97x0.93x0.97x496)=0.205m³第二级气缸行程容积V‘h2=Vdnps1pd1Ts2Ts1λφλv2∙λp2∙λt2∙λl2V’h2=70×0.11×303×1496×3.57×291×0.75×0.99×0.93×0.97=0.061m³5)复算气缸直径第一级气缸直径D1=√(2×0.205/3.14/0.24+0.07²/2)=0.74m第二级气缸直径D2=√(2×0.061/3.14/0.24+0.07²/2)=0.404m气缸直径圆整后，仍能满足设计要求八、各级压力及压力比第一级实际进气压力p's1=(1-δs1)ps1=(1-0.03)0.11=0.1067MPa第一级实际排气压力p'd1=(1+δd1)pd1=(1+0.07)0.398=0.426MPa第二级实际吸气压力p's2=(1-δs2)ps2=(1-0.023)0.398=0.417MPa第二级实际排气压力p'd2=(1+δd2)pd2=(1+0.054)1.4=1.475MPa第一级实际压力比ε'1=ε1(1+δ1)=3.62(1+0.1)=3.985第二级实际压力比ε'2=ε2(1+δ2)=3.51(1+0.077)=3.782九、功率计算Ni=n60p′siλ′viV′hinini−1{[εi(1+δ0i)]ni−1ni−1}N1=49660×0.1067×0.7899×0.205×1.241.24−1{[3.62(1+0.1)]1.24−11.24−1}=226871.7WN2=49660×0.417×0.7567×0.061×1.241.24−1{[3.51(1+0.077)]1.24−11.24−1}=243187.4W总的指示功率Ni=N1+N2=226871+243187=470059W机械效率ηm=0.94轴功率Nz=Ni/ηm=470059/0.94=500066.5W十、各级压缩终了温度第一级压缩终了温度T1=Ts1*ε’1(n-1)/n=291×3.985(1.243-1)/1.243=381.3K/108.3℃第二级压缩终了温度T2=Ts2*ε’2(n-1)/n=303×3.782(1.268-1)/1.268=401.5K/128.5℃第一级排气温度Td1=Ts1*ε1(n-1)/n=291×3.62(1.243-1)/1.243=374.3K/101.3℃第二级排气温度Td2=Ts2*ε2(n-1)/n=303×3.51(1.268-1)/1.268=395.3K/122.3℃十一、活塞气体力第一级活塞面积盖侧Ac1=πD1²/4轴侧As1=Ac1-πd²/40.4300840270.426235576第二级活塞面积盖侧Ac2=πD1²/4轴侧As2=Ac2-πd²/40.1320254290.128176978外止点内止点一级所受最大活塞力Fa1=-p'd1Ac1+p's1As1-137897.4NFt1=-p's1Ac1+p'd1As1135845.9N二级所受最大活塞力Fa2=-p'd2Ac2+p's2As2-141360.7NFt2=-p's2Ac2+p'd2As2134080.6N各列受力均匀度u=(ƖPmaxƖ+ƖPminƖ)/(2ƖPmaxƖ)=1.02u0.6十二、气缸压力指示图s0ss0Ⅰ级盖侧Ⅰ级轴侧外止点内止点Ⅰ级气缸压力指示图第一级纵坐标第二级纵坐标线性余隙容积S0=S*a0.0240.0288盖侧吸气端气体力Fcs=Acp'sN45889.9656730.0299562154997.5214435.98985391盖侧排气端气体力Fcd=Acp'dN183376.7536120194755.1112127.4458888轴侧吸气端气体力Fss=Asp'sN45479.3359529.7612440353394.3812834.94077427轴侧排气端气体力Fsd=Asp'dN181735.8732118.9262235189078.1328123.7309282气缸压力指示图横坐标单位：mm，线性余隙容积S01=S*a1=240×0.1=24mm，S02=S*a2=240×0.12=28.8mm，纵坐标取第一级盖侧排气端气体力为基准，高度120mm，比例因子k=183376.7536/120=1258.14N/mm。气体力指示图复核盖侧指示图面积S1mm28934.12019779.5287轴侧指示图面积S2mm28832.55729415.252