两列二级二缸双作用无油润滑对称平衡型热力、动力计算

1、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、工艺参数级名义吸气压力 p1=0.01MPa(表压) 吸气温度Ts1=18级名义排气压力 p1=1.3MPa(表压) 吸气温度Ts2=30排气量（级吸入状态）Vd=70m³/min级排气温度 Td2140相对湿度 =0.8三、结构参数活塞行程：S=2r=2 x 120=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

2、：名称级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= pd2 / ps1=12.73压力比分配1=2=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

3、.110.110.11Zm1=(XiZi)0.953406一级排气N2CH4C2H6C3H8C4H10C5H12Z1d1110.960.940.9排气温度 K373.1691373.1691373.1691373.1691373.1691373.1691排气压力 Mpa0.3924280.3924280.3924280.3924280.3924280.392428Zm2=(XiZi)0.958203二级吸气一级排气N2CH4C2H6C3H8C4H10C5H12Z1d1110.90.90.9排气温度 K303303303303303303排气压力 Mpa0.3924280.3924280.392

4、4280.3924280.3924280.392428Zm3=(XiZi)0.953406二级排气N2CH4C2H6C3H8C4H10C5H12Z2d110.980.960.760.74排气温度 K396.5906396.5906396.5906396.5906396.5906396.5906排气压力 Mpa1.31.31.31.31.31.3Zm4=(XiZi)0.948958三、过程指数绝热指数KmN2CH4C2H6C3H8C4H10C5H12Vi1.071%80.154%4.446%5.912%3.125%1.707%k1.41.321.271.161.11.081Km-1=ViKi-1

5、=3.59Km=1.268n1=0.98 x Km=1.243n2=Km=1.268四、各级排气温度排气温度Td=Ts(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v= 1-a(1/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

6、数v1=1-0.1(3.57(1/1.134)-1)=0.79第二级容积系数v2=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 s10.03进气相对压力损失 s20.023排气相对压力损失 d10.07排气相对压力损失 d20.053666667相对压力损失01=s1+d10.1相对压力损失02=s2+d20.076666667压力系数p=1-(1+a)pa/(nvp1)进气压力损失pa= ps s第一级进气压力损失pa1= ps1 s1=0.11x0.03=0.0033第二级进气压力损失pa2= ps2 s2=0.39x0.03=0.009第一

7、级压力系数p1=1-(1+0.1)0.0033/(1.243x0.79x0.11)=0.97第二级压力系数p2=1-(1+0.12)0.009/(1.268x0.75x0.39)=0.993)温度系数t1=t2=0.934)析水系数=(p1-ps1)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= 0.0042455Mpa=0.11-0.8X0.00206440.390.39-0.0090.11=1第二级排气温度下的饱和蒸汽压力ps3=0.21809Mpa，ps1=0.021Mpa< ps3，第二级排气处无水析出

8、。5)泄漏系数l泄漏系数l第一级第二级气阀0.020.02活塞环0.0060.006填料0.0010.001l=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/(v1p1t1l1n)Vh1=70/(0.79 x 0.97 x 0.93 x 0.97 x 496)=0.204 m³第二级气缸行程容积Vh2=Vdnps1pd1Ts2Ts1v2p2t2l2Vh2=70×0.11×303×1496×3.57×291×0.75×0.99×0

9、.93×0.97=0.061m³2)气缸直径计算气缸直径D=(2Vh/sz+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D1=0.74m第二级气缸直径D2=0.41m4)第一级缸径比1=s/D1=0.24/0.74=0.324 第二级缸径比2=s/D2=0.24/0.41=0.585 活塞平均速度vm= sn/30=0.24×496/30=3

10、.968 m/s七、复算压力比1)圆整后行程容积V'h1=s(2D1²-d²)/4=0.24×3.14×(2×0.74²-0.07²)/4 =0.206 m³V'h2=s(2D2²-d²)/4=0.24×3.14×(2×041²-0.07²)/4 =0.062 m³2)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.

11、206/0.061=0.398 MPa第一级名义压力比1=pd1/ps1=0.398/0.11=3.62第二级名义压力比2=pd2/ps2=1.4/0.398=3.513)复算容积系数第一级容积系数v1=1-0.1(3.62(1/1.13)-1)=0.7889第二级容积系数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/(v1p1t1l1n)Vh1=70/(0.7889 x 0.97 x 0.93 x 0.97 x 496)=0.205 m³第二级气缸行程容积Vh2=Vdnps1pd1Ts2Ts1v2p2t2l2Vh

12、2=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-s1)ps1=(1-0.03)0.11=0.1067 MPa第一级

13、实际排气压力p'd1=(1+d1)pd1=(1+0.07)0.398=0.426 MPa第二级实际吸气压力p's2=(1-s2)ps2=(1-0.023) 0.398=0.417 MPa第二级实际排气压力p'd2=(1+d2)pd2=(1+0.054)1.4=1.475 MPa第一级实际压力比'1=1(1+1)= 3.62(1+0.1)=3.985第二级实际压力比'2=2(1+2)= 3.51(1+0.077)=3.782九、功率计算Ni=n60p'si'viV'hinini-1i(1+0i)ni-1ni-1N1=49660

14、15;0.1067×0.7899×0.205×1.241.24-13.621+0.11.24-11.24-1=226871.7 WN2=49660×0.417×0.7567×0.061×1.241.24-13.511+0.0771.24-11.24-1=243187.4 W总的指示功率Ni= N1+ N2=226871+243187=470059 W机械效率m=0.94轴功率Nz= Ni/m=470059/0.94=500066.5 W十、各级压缩终了温度第一级压缩终了温度T1=Ts1*1(n-1)/n=291×3

15、.985(1.243-1)/1.243=381.3K /108.3第二级压缩终了温度T2=Ts2*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*1(n-1)/n=291×3.62(1.243-1)/1.243=374.3K / 101.3第二级排气温度Td2=Ts2*2(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=D1²/4轴侧As1=Ac1-d²/40.4300840270.4

16、26235576第二级活塞面积盖侧Ac2=D1²/4轴侧As2=Ac2-d²/40.1320254290.128176978外止点内止点一级所受最大活塞力Fa1=-p'd1Ac1+p's1As1-137897.4 NFt1=-p's1Ac1+p'd1As1135845.9 N二级所受最大活塞力Fa2=-p'd2Ac2+p's2As2-141360.7 NFt2=-p's2Ac2+p'd2As2134080.6 N各列受力均匀度u=(Pmax+Pmin)/(2Pmax)=1.02u>0.6十二、气缸压力指示

17、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

18、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=1258.14 N/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S2mm28832.55729415.2526盖侧循环指示功Wc=S1k/1000N.m13652.5828414944.48521轴侧循环指示功Ws=S2k/1000N.m13497.3805414387.82047总的指示功W=Wc+W

19、sN.m27149.9633829332.30567指示功率N=Wn/60W224439.6973242480.3936误差=(Ni-N)/Ni1.32%0.06%过程指数复核过程指数n=lg(pd/ps)/lg(S/S'd)1.2711.2435压缩终了时气缸容积的长度S'd（由气体力指示图求得）99.4686.65误差-0.27%-0.03%膨胀指数n=lg(ps/pd)/lg(Sd/S's)1.16581.132膨胀终了时气缸容积的长度S'd（由气体力指示图求得）85.281.61误差0.05%0.21%十三、惯性力计算活塞重量m1kg188.76162.

20、69十字头重量m2kg89.0389.03连杆重量mlkg86.02586.025m'l=0.4mlkg34.4134.41往复运动质量ms=m1+m2+m'lkg312.2286.13曲轴半径rm 0.120.12曲轴旋转角速度w=n/3051.94151.941连杆长度lm 0.60.6曲轴旋转半径与连杆长度比=r/l0.20.2第一级纵坐标第二级纵坐标最大惯性力Imax=msrw2(1+)121287.579.36937111159.572.7417最小惯性力Imin=-msrw2(1-)-80858.3-52.9129-74106.3-48.4945惯性力图复核第一级第二级S14111.7633776.139S24135.0143789.235S1/S20.9943770.996544十四、综合活塞力图摩擦力计算第一级纵坐标第二级纵坐标摩擦力Ff=0.65Ni(1/m-