南京航空航天大学·能源与动力学院航空燃气涡轮发动机原理大作业设计题目:涡轮喷气发动机气动热力计算小组成员:XXX0207105??YYY0207105??ZZZ0907601??指导教师:AAA日期:2010/12/12航空燃气涡轮发动机原理大作业报告一、设计要求:海平面、静止状态、标准大气条件,最大工作状态时,对有关涡轮喷气发动机的F,SFC的要求如下表所示,它们均采用收敛喷管,col为压气机相对引气量,R为涡轮中的相对回气量。试选择有关参数,计算画出sF,SFC及maq随*k(或*3T)的变化关系曲线,并确定满足性能要求的工作过程参数。发动机ABCDEFcol0.030.02500.0300R0.020.0200.0200要求()FdN26001250700290026502200(/)SFCKgdNhr0.951.01.20.961.21.1二、设计计算1、参数选择(以A组要求为准)(1)物性参数:空气比热:1.005/pKJKgC燃气比热:'1.1607/pKJKgC空气绝热指数:1.4k燃气绝热指数:'1.3k空气气体常数:287/JKgKR燃气气体常数:'288/JKgKR燃油低热值:42900/HuKJKg(2)发动机及各部件参数:发动机推力:2600FdN进气道总压恢复系数:0.97i压气机效率:*0.78k燃烧室总压恢复系数:0.905b燃烧效率:0.96b涡轮效率:*0.88t轴机械传动效率:0.98m尾喷管总压恢复系数:0.96e压气机相对引气量:0.03col涡轮中的相对回气量:0.02R2、热力计算及结果输出热力计算过程参数计算过程采用定比热计算方法,对涡轮喷气发动机工作过程参数进行初步计算。过程与书上给出过程一致,油气比的计算采用等温焓差法,为计算方便起见,根据文献【3,13】提供公式和方法,算出油气比随燃烧室进出口温度变化关系,通过曲线拟合可得油气比5()495727.0197799.00110966.0[(2*38*341010TTff-)]2.000258.0)(01.0*36*210TT采用matlab语言编程分别对涡轮前燃气温度一定,单位推力和耗油率随增压比(压气机总压比)的变化情况及增压比(压气机总压比)一定,单位推力和耗油率随涡轮前燃气温度的变化情况两种情况进行计算。(1)编程代码如下:clcclear%%飞行条件%%%%%%%%%%%%%%h=0;m0=0;%%%%%%%%%%%%%%%%%%%%%%物性参数及各主要部件的参数%%%%%%%%%%%%%%%%%%物性参数cp=1005;cpp=1160.7;k=1.4;kp=1.33;r=287;rp=288;hu=42900000;%%发动机各部件参数cgmi=0.97;adkx=0.78;ksb=0.96;cgmb=0.905;adtx=0.88;adm=0.98;cgme=0.96;vcol=0.03;vr=0.02;%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%设计推力%%ft=26000;%%%%%%%%%%%涡轮前燃气温度一定时的执行本段%%%%%%%fori=1:363t3x(i)=1200;pkx(i)=1.32+(i-1)/10;%%%%%%%%%%%%%%%%%%%%%%%%%%%%%压气机压比一定时执行本段%%%%%%%%%%%%fori=1:3000%%t3x(i)=900+i*0.5;%%pkx(i)=12;%%%%%%%%%%%%%%%%%%%%%%%%%%%%%本段为涡轮喷气发动机气动热力计算过程%%%%%%%%%%%%%%%%%%根据给定飞行高度h确定该高度的大气温度t0和p0p0=1.01325*(1-h/1000/44.308)^5.2553*10^5;t0=288.15-6.5*h/1000;%%进气道出口参数t0x=t0*(1+(k-1)/2*m0^2);t1x=t0x;p1x=cgmi*p0;%%压气机出口参数dttkx(i)=t1x*(pkx(i)^((k-1)/k)-1)/adkx;t2x(i)=t1x+dttkx(i);p2x(i)=p1x*pkx(i);%%燃烧室出口参数p3x(i)=cgmb*p2x(i);%%油气比计算(等温焓差法)thetaf=0.97*42900000/ksb/hu;f(i)=thetaf*(-0.0110966+0.197799*10^(-4)*t3x(i)+0.495727*10^(-8)*t3x(i)^2+(5-0.01*t2x(i))*(0.00258+0.2*10^(-6)*t3x(i)));%%涡轮出口气流参数dtttx(i)=cp*dttkx(i)/cpp/(1-vcol+f(i))/adm;t4x(i)=t3x(i)-dtttx(i);ptx(i)=(1-dtttx(i)/t3x(i)/adtx)^(-kp/(kp-1));p4x(i)=p3x(i)/ptx(i);%%尾喷管出口气流参数p9x(i)=p4x(i)*cgme;t9x(i)=t4x(i);gmcr=(2/(kp+1))^(kp/(kp-1));gm(i)=p0/p9x(i);ifgm(i)gmcrc9(i)=sqrt(2*cpp*t4x(i)*(1-(p0/cgme/p4x(i))^((kp-1)/kp)));p9(i)=p0;elsec9(i)=sqrt(2*kp*rp*t4x(i)/(kp+1));p9(i)=cgme*p4x(i)/(kp/2+1/2)^(kp/(kp-1));endt9(i)=t4x(i)-c9(i)^2/2/cpp;%%发动机的单位推力fs(i)=(1-vcol+f(i)+vr)*(c9(i)+rp*t9(i)*(1-p0/p9(i))/c9(i));%%流过发动机的空气流量qma(i)=ft/fs(i);%%发动机的耗油率sfc(i)=36000*f(i)*(1-vcol)/fs(i);end%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%涡轮前燃气温度一定执行本段%%%%%%%%%%%%%%%涡轮前燃气温度一定时的图形输出figureplot(pkx,sfc,'b');xlabel('pkx');ylabel('SFC/(kg/(dN*h))');axis([04005]);figureplot(pkx,fs,'g')xlabel('pkx');ylabel('Fs/(N/kg)');figureplot(pkx,qma,'r')xlabel('pkx');ylabel('qma/(kg/s)');axis([0400300]);%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%当压气机压比一定时执行本段%%%%%%%%%%%%%%压气机压比一定时的图形输出%%figure%%plot(t3x,sfc,'b');%%xlabel('t3x');ylabel('SFC/(kg/(dN*h))');%%axis([800200005]);%%figure%%plot(t3x,fs,'g')%%xlabel('t3x');ylabel('Fs/(N/kg)');%%figure%%plot(t3x,qma,'r')%%xlabel('t3x');ylabel('qma/(kg/s)');%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%(2)图形输出如下1)涡轮前燃气温度*31200T,单位推力和耗油率随增压比(压气机总压比)的变化情况;051015202530354000.511.522.533.544.55X:12.32Y:0.9088pkxSFC/(kg/(dN*h))05101520253035400100200300400500600700X:12.32Y:575.4pkxFs/(N/kg)0510152025303540050100150200250300X:12.32Y:45.18pkxqma/(kg/s)2)增压比(压气机总压比)*12k时,单位推力和耗油率随涡轮前燃气温度的变化情况:80010001200140016001800200000.511.522.53t3xSFC/(kg/(dN*h))X:1270Y:0.9459800100012001400160018002000220024000200400600800100012001400t3xFs/(N/kg)X:1270Y:641.5800100012001400160018002000050100150200250300350400t3xqma/(kg/s)X:1270Y:40.56三、设计总结:影响发动机单位性能参数主要工作过程参数是*k和*3T。对于压比*k影响,随压比*k增加单位推力增加,耗油率下降;sF最大位置为最佳增压比opt,SFC最小的压比为最佳经济压比ec,且ec大于opt;对于涡轮前燃气温度*3T的影响,随*3T增加单位推力增加,耗油率先降低后升高,其最低点为最经济涡轮前燃气温度*3ecT;从图中可以看出,发动机工作过程参数*k和*3T的选择,不可能同时满足推力性能即经济性的要求,应综合考虑发动机非设计点性能及部件设计水平,目前新材料、新技术的发展等因素。力争在满足性能要求前提下,尽可能使发动机尺寸小、重量轻、寿命长、维护操作方便、工作安全可靠。