您好,欢迎访问三七文档
山东104总吨钢质拖网渔船1.已知船体主要参数船型:单桨,转动导流管平衡舵,尾机型钢质拖网渔船。设计水线长:Lwl=27.50m垂线间长:Lpp=26.00m型宽:B=5.40m型深:D=2.50m平均吃水:Tm=1.90m尾吃水:Ta=2.40m方形系数:Cb=0.502棱形系数:Cp=0.592宽吃水比:B/Tm=2.84排水量:Δ=137.35t浮心纵向坐标(LCB):Xb=-0.78m桨轴中心距基线:Zs=0.35m用艾亚法估算船体有效功率数据表:首先计算所需参数如下:L/Δ1/3=5.04Δ0.64=23.346Xc=-3%速度v(kn)91011速长比V/L1/20.9741.0831.191傅汝德数Vs/(gL)1/20.2900.3220.354标准Co查图7-3295243205标准Cbc,查表7-50.5930.560.546实际Cb(肥或瘦)(%)15.35,瘦10.36,瘦8.06,瘦Cb修正(%)11.217.1745.104Cb修正数量△1331710已修正Cb之△1328260215B/T修正(%)=-10Cb(B/T-2)%-4.2168-4.2168-4.2168B/T修正数量,△2[式7-23]-14-11-9已修正B/T之C2314249206标准Xc,%L,船中前或后,查表7-51.838,船中后2.3275,船中后2.4955,船中后实际Xc,%L,船中前或后3,船中后3,船中后3,船中后相差%L,在标准者前或后1.162,后0.6725,后0.5045,后Xc修正(%),查表7-7(b)0.220.50.96Xc修正数量,△3[式(7-24)]-1-1-2已修正Xc之C3313248204长度修正(%)=(Lwl-1.025Lbp)/Lwl*100%3.23.23.2长度修正数量,△4[式(7-25)]1087已修正长度C4323256211Vs372910001331Pe=△0.64*Vs3/C4*0.735(KW)39681092.主机参数主机型号6160A-123功率(KW)136转速(转/分)850齿轮箱型号2HC250减速比1.97:13.推进因子的确定(1)伴流分数ω本船为单桨钢质拖网渔船,故使用汉克歇尔公式估算:ω=0.77*Cp-0.28=0.77*0.592-0.28=0.176(2)推力减额分数t对于单螺旋桨渔船,也使用汉克歇尔公式估算:t=0.77*CP-0.30=0.77*0.592-0.30=0.156(3)相对旋转效率缺少资料,故近似地取为ηR=1.0(4)船身效率ηH=(1-t)/(1-ω)=(1-0.156)/(1-0.176)=1.02434.桨叶数Z的选取根据一般情况,单桨船多用四叶,加之教材中四叶图谱资料较为详尽、方便查找,故选用四叶。5.AE/A0的估算按公式AE/A0=(1.3+0.3*Z)*T/(P0-Pv)D允许2+k进行估算:其中:在设计航速时,PE=71.5KW,V=10.1knT=PE/(1-t)V=71.5/((1-0.156)*10.1*0.5144)=16.306kN水温15℃时汽化压力Pv=174kgf/m2=174*9.8N/m2=1.705kN/m2静压力为:P0=Pa+γhs=(10330+1025*(2.4-0.35))*9.8N/m2=121.826kN/m2k取0.2由型线图量得:D允许=1.5mAE/A0=(1.3+0.3*Z)*T/(P0-Pv)D允许2+k=(1.3+0.3*4)*16.306/((121.826-1.705)*1.52)+0.2=0.3516.桨型的选取说明目前在商船螺旋桨设计中,以荷兰的楚思德B型螺旋桨和日本AU型(当然包括其改进型,以MAU表示之)螺旋桨应用最为广泛。另外鉴于课本上只有AU型图谱资料,为方便螺旋桨制图选用MAU螺旋桨。7.根据估算的AE/A0选取2~3张图谱,计算可以达到最大航速根据AE/A0=0.4003选取MAU4-40,MAU4-55,MAU4-70三张图谱。功率储备取10%,轴系效率ηS=0.98,齿轮箱效率ηG=0.96则螺旋桨敞水收到功率PDO=PS*0.9*ηS*ηG*ηR=136*0.9*0.98*0.96*1.0=115.154kW=156.67hp8.列表按所选图谱进行终结设计,得到3组螺旋桨的要素及最大航速VSMAX其中,螺旋桨转速为:N=n/i=850/1.97=431.47r/min根据MAU4-40,MAU4-55,MAU4-70的PB-δ图谱列表计算。项目单位数值假定航速Vkn9.00010.00011.000VA=(1-ω)*Vkn7.4168.2409.064Bp=N*PD0.5/VA2.536.05927.70921.835Bp1/26.0055.2644.673MAU4-40δ70.00063.00057.000P/D0.6800.7100.750ηO0.5800.6150.643PTE=PDOηHηOhp93.07798.693103.187MAU4-55δ68.50061.00055.000P/D0.7200.7600.810ηO0.5650.5950.630PTE=PDOηHηOhp90.67095.484101.101MAU4-70δ67.00060.40054.500P/D0.7300.7700.830ηO0.5450.5750.595PTE=PDOηHηOhp87.46092.27495.484根据表中的计算结果可绘制PTE,δ,P/D及η0对V的曲线,如下图所示:结论:从PTE-f(V)曲线与船体有效马力曲线之交点,可获得不同盘面比所对应的设计航速及螺旋桨最佳要素P/D、D及η0如下表所列。MAUVmax/knP/DδD/mη04-4010.14500.715262.07441.45950.61924-5510.07200.763360.52521.41290.59754-709.99420.769760.43631.39990.5750用图形反映上述数据的变化趋势:说明:由于空泡校核结果,所需盘面比小于0.40,故图中没有画要求的盘面比曲线(校核过程如下)。9.空泡校核,由图解法求出不产生空泡的(AE/A0)MIN及相应的VsMAX、P/D、η0、D按柏利尔空泡限界线中适用于拖船,拖网渔船的下限曲线,计算不发生空泡之最小展开面积比。桨轴沉深hs由船体型线图取hs=2.4-0.35=2.05mp0-pv=pa+γhs-pv=(10330+1025*2.05-174)kgf/m2=12431.25kgf/m2计算温度t=15℃,pv=174kgf/m2,PDO=PS*0.9*ηS*ηG*ηR=136*0.9*0.98*0.96*1.0=115.154kW=156.67hp空泡校核计算表如下:序号项目单位数值MAU4-40MAU4-55MAU4-701Vmaxkn10.14510.0729.9942VA=0.5144*Vmax(1-ω)m/s4.3004.2694.2363(0.7*π*N*D/60)2(m/s)2532.185498.743489.6084V0.7R2=VA2+(3)2(m/s)2550.676516.969507.5535σ=(p0-pv)/0.5*ρ*V0.7R20.4260.4530.4626τc(查图6-20)0.1350.1400.1427T=PD*η0*75/VAkgf1691.9901644.5271594.9198Ap=T/0.5*ρ*V0.7R2*τcm20.4350.4340.4239AE=Ap/(1.067-0.229P/D)m20.4820.4870.47510AE/A0=AE/(0.25*π*D*D)0.2880.3110.309对上述计算结果进行分析可知,由于该船尾吃水较大,导致螺旋桨浸深足够大,不发生空泡所需盘面比较小,故直接选择MAU4-40螺旋桨。由此可求得不发生空泡的最小盘面比以及所对应的最佳螺旋桨要素:AE/A0=0.40,P/D=0.7152,D=1.4595m,η0=0.6192,VMAX=10.145kn。10.计算与绘制螺旋桨无因次敞水性征曲线由MAU4-40的敞水性征曲线插值求得所需敞水性征曲线相关数据,列表如下:J00.10.20.30.40.50.60.70.8KT0.3010.2690.2420.2120.1750.1380.10.0550.00810KQ0.3190.2920.2720.2460.2170.1850.1430.1020.055η000.1510.2850.4170.5250.6170.6760.6330.267由上述表格数据画出设计桨的敞水性征曲线:11.计算船舶系泊状态时螺旋桨有效推力与保持转矩不变的转速N0由敞水性征曲线得J=0时,KT=0.301,KQ=0.0319。计算功率PD=136*0.98*0.96=127.95kW=174.08hp系柱推力减额分数取t0=0.04,主机转矩Q=PD*60*75/(2πN)=174.08*60*75/(2*3.1416*431.47)=289.1kgf*m系柱推力T=(KT/KQ)*(Q/D)=(0.301/0.0319)*(289.1/1.4595)=1869.06kgf螺旋桨转速N0=60*)K*D*T/(T4=60*(1869.06/(104.63*1.45954*0.301))0.5=217.02rpm12.桨叶强度校核按我国2001年《钢质海船入级与建造规范》校核t0.25R及t0.6R,应不小于按下式计算所的之值:XKYt(mm)式中:K为材料系数;Y=1.36*A1*Ne/(Z*b*N);X=A2*G*Ad*N2*D3/(1010*Z*b);A1=D/P(K1-K2*D/P0.7)+K3*D/P0.7-K4;A2=(D/P)*(K5+K6*ε)+K7*ε+K8;计算功率Ne=136*0.98*0.96=127.95kW=174.08hpAd=AE/A0=0.40,P/D=0.7152,ε=10º,G=8.3g/cm3,N=431.47rpm在0.66R处切面弦长b0.66R=0.226*AE/A0*D/(0.1*Z)=0.226*0.4*1.4595/0.4=0.3298mb0.25R=0.7212*b0.66R=0.7212*0.3298=0.2379mb0.6R=0.9911*b0.66R=0.9911*0.3298=0.3269m强度校核计算表如下:项目单位数值0.25R0.6R弦长bm0.23790.3269K1634207K2250151K31410635K4434A1=D/P(K1-K2*D/P0.7)+K3*D/P0.7-K42365.1938848.0893Y=1.36*A1*Ne/(Z*b*N)1002.3996261.5744K58223K63412K74165K8380330A2=(D/P)*(K5+K6*ε)+K7*ε+K81380.04471179.9441材料系数K(Cu1锰青铜)1.00001.0000X=A2*G*Ad*N2*D3/1010*Z*b0.27870.1734t=[Y/(K-X)]0.5mm37.278117.7889MAU标准桨叶厚度t'mm55.825931.8171校核结果满足要求满足要求实取桨叶厚度mm55.825931.817113.桨叶轮廓及各半径切面的型值计算a.叶片最大宽度在0.66R处,其值为:b0.66R=0.226*AE/A0*D/(0.1*Z)=0.226*0.4*1.4595/0.4=0.3298mb.叶片最大厚度在螺旋桨轴线处,其值为:tmax=0.05*D=0.05*1.4595*1000=72.975mm其它桨叶尺寸见如下表格:(单位:m)叶片最大宽度0.33螺旋桨直径1.46r/R0.200.300.400.500.600.700.800.900.95母线至叶片随边的距离0
本文标题:螺旋桨-课程设计
链接地址:https://www.777doc.com/doc-7316837 .html