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1、1.3matlab程序：（1）%驱动力-行驶阻力平衡图%货车相关参数。 m=3880;g=9.8;nmin=600;nmax=4000;G=m*g;ig=5.56 2.769 1.644 1.00 0.793;y=0.85;r=0.367;f=0.013;CdA=2.77;i0=5.83;L=3.2;a=1.947;hg=0.9;If=0.218;Iw1=1.798;Iw2=3.598;n=600:10:4000; %发动机转数转换成汽车行驶速度。ua1=0.377*r*n/ig(1)/i0;ua2=0.377*r*n/ig(2)/i0;ua3=0.377*r*n/ig(3)/i0;ua4=0
2、.377*r*n/ig(4)/i0;ua5=0.377*r*n/ig(5)/i0; %计算各档位驱动力。Tq=-19.313+295.27*(n/1000)-165.44*(n/1000).2+40.874*(n/1000).3-3.8445*(n/1000).4;Ft1=Tq*ig(1)*i0*y/r;Ft2=Tq*ig(2)*i0*y/r;Ft3=Tq*ig(3)*i0*y/r;Ft4=Tq*ig(4)*i0*y/r;Ft5=Tq*ig(5)*i0*y/r; %计算行驶阻力。Fz1=m*g*f+2.77*ua1.2/21.15; Fz2=m*g*f+2.77*ua2.2/21.15;Fz3
3、=m*g*f+2.77*ua3.2/21.15;Fz4=m*g*f+2.77*ua4.2/21.15;Fz5=m*g*f+2.77*ua5.2/21.15; %驱动力-行驶阻力平衡图。plot(ua1,Ft1,ua2,Ft2,ua3,Ft3,ua4,Ft4,ua5,Ft5,ua1,Fz1,k,ua2,Fz2,k,ua3,Fz3,k,ua4,Fz4,k,ua5,Fz5,k);title(驱动力-行驶阻力平衡图); xlabel(ua(km/s);ylabel(Ft(N);legend(Ft1,Ft2,Ft3,Ft4,Ft5,Ff+Fw) %求最高车速。x,y=ginput(1);disp(汽车最
4、高车速=);disp(x);disp(km/h);（2）%汽车最大爬坡度 clearclc%汽车相关参数。m=3880;g=9.8;nmin=600;nmax=4000;G=m*g;ig=5.56 2.769 1.644 1.00 0.793;y=0.85;r=0.367;f=0.013;CdA=2.77;i0=5.83;L=3.2;a=1.947;hg=0.9;If=0.218;Iw1=1.798;Iw2=3.598;n=600:10:4000;Tq=-19.313+295.27*(n/1000)-165.44*(n/1000).2+40.874*(n/1000).3-3.8445*(n/1
5、000).4;Ft1=Tq*ig(1)*i0*y/r; %一档时爬坡能力最强。ua1=0.377*r*n/ig(1)/i0;Ff=G*f; %滚动阻力。Fw1=CdA*ua1.2/21.15; %空气阻力。Fz1=Ff+Fw1;Fi1=Ft1-Fz1;Fmax=max(Fi1/G);imax=100*tan(asin(Fmax);disp(汽车最大爬坡度=);disp(imax),disp(%);（3）%求汽车加速度倒数曲线和最大爬坡度显得附着率。 clearclcm=3880; %汽车相关参数。g=9.8;nmin=600;nmax=4000;G=m*g;ig=5.56 2.769 1.64
6、4 1.00 0.793;y=0.85;r=0.367;f=0.013;CdA=2.77;i0=5.83;L=3.2;a=1.947;hg=0.9;If=0.218;Iw1=1.798;Iw2=3.598; n=600:10:4000; %发动机转速范围。Tq=-19.313+295.27*(n/1000)-165.44*(n/1000).2+40.874*(n/1000).3-3.8445*(n/1000).4; Ft1=Tq*ig(1)*i0*y/r; %各档位下的驱动力。Ft2=Tq*ig(2)*i0*y/r;Ft3=Tq*ig(3)*i0*y/r;Ft4=Tq*ig(4)*i0*y/r
7、;Ft5=Tq*ig(5)*i0*y/r; ua1=0.377*r*n/ig(1)/i0; %各档位下的车速。ua2=0.377*r*n/ig(2)/i0;ua3=0.377*r*n/ig(3)/i0;ua4=0.377*r*n/ig(4)/i0;ua5=0.377*r*n/ig(5)/i0; Fw1=CdA*ua1.2/21.15; %空气阻力。Fw2=CdA*ua2.2/21.15;Fw3=CdA*ua3.2/21.15;Fw4=CdA*ua4.2/21.15;Fw5=CdA*ua5.2/21.15; Ff=G*f; %滚动阻力。 q1=1+(Iw1+Iw2)/(m*r2)+(If*ig(
8、1)2*i02*y)/(m*r2); %求各档位下的汽车旋转质量换算系数。q2=1+(Iw1+Iw2)/(m*r2)+(If*ig(2)2*i02*y)/(m*r2);q3=1+(Iw1+Iw2)/(m*r2)+(If*ig(3)2*i02*y)/(m*r2);q4=1+(Iw1+Iw2)/(m*r2)+(If*ig(4)2*i02*y)/(m*r2);q5=1+(Iw1+Iw2)/(m*r2)+(If*ig(5)2*i02*y)/(m*r2); a1=(Ft1-Ff-Fw1)/(q1*m); %求出汽车加速度。a2=(Ft2-Ff-Fw2)/(q2*m);a3=(Ft3-Ff-Fw3)/(q
9、3*m);a4=(Ft4-Ff-Fw4)/(q4*m);a5=(Ft5-Ff-Fw5)/(q5*m); ad1=1./a1; ;%求加速度倒数。ad2=1./a2;ad3=1./a3;ad4=1./a4;ad5=1./a5; plot(ua1,ad1,ua2,ad2,ua3,ad3,ua4,ad4,ua5,ad5); %绘制加速度倒数曲线。axis(0 100 0 10);title(汽车的加速度倒数曲线);xlabel(ua(km/h);ylabel(1/a);legend(ad1,ad2,ad3,ad4,ad5) %求最大爬坡度时的附着率。Fz=Ft1-Ff-Fw1;aa=asin(max
10、(Fz)/G); %最大爬坡角度。C=tan(aa)/(a/L+hg*tan(aa)/L); %附着率。disp(假设后轮驱动，最大爬坡度相应的附着率=);disp(C);（4）%求汽车2档原地起步换挡加速行驶至70km/h的加速时间clearnT=0.85;r=0.367;f=0.013;CDA=2.77;i0=5.83;If=0.218;Iw1=1.798;Iw2=3.598;L=3.2;a=1.947;hg=0.9;m=3880;g=9.8;ig=5.56 2.769 1.644 1.00 0.793;G=m*g;nmin=600;nmax=4000;u1=0.377*r*nmin./i
11、g/i0;u2=0.377*r*nmax./ig/i0;deta=0*ig;for i=1:5 deta(i)=1+(Iw1+Iw2)/(m*r2)+(If*(ig(i)2*i02*nT)/(m*r2);endua=6:0.01:99;N=length(ua);n=0;Tq=0;Ft=0;inv_a=0*ua;delta=0*ua;Ff=G*f;Fw=CDA*ua.2/21.15;for i=1:N k=i; if ua(i)=u2(2) n=ua(i)*(ig(2)*i0/r)/0.377; Tq=-19.313+295.27*(n/1000)-165.44*(n/1000)2+40.874
12、*(n/1000)3-3.8445*(n/1000)4; Ft=Tq*ig(2)*i0*nT/r; inv_a(i)=(deta(2)*m)/(Ft-Ff-Fw(i); delta(i)=0.01*inv_a(i)/3.6; elseif ua(i)=u2(3) n=ua(i)*(ig(3)*i0/r)/0.377; Tq=-19.313+295.27*(n/1000)-165.44*(n/1000)2+40.874*(n/1000)3-3.8445*(n/1000)4; Ft=Tq*ig(3)*i0*nT/r; inv_a(i)=(deta(3)*m)/(Ft-Ff-Fw(i); delta
13、(i)=0.01*inv_a(i)/3.6; elseif ua(i)=u2(4) n=ua(i)*(ig(4)*i0/r)/0.377; Tq=-19.313+295.27*(n/1000)-165.44*(n/1000)2+40.874*(n/1000)3-3.8445*(n/1000)4; Ft=Tq*ig(4)*i0*nT/r; inv_a(i)=(deta(4)*m)/(Ft-Ff-Fw(i); delta(i)=0.01*inv_a(i)/3.6; else n=ua(i)*(ig(5)*i0/r)/0.377; Tq=-19.313+295.27*(n/1000)-165.44*
14、(n/1000)2+40.874*(n/1000)3-3.8445*(n/1000)4; Ft=Tq*ig(5)*i0*nT/r; inv_a(i)=(deta(5)*m)/(Ft-Ff-Fw(i); delta(i)=0.01*inv_a(i)/3.6; end a=delta(1:k); t(i)=sum(a);endplot(t,ua);axis(0 80 0 100);title(汽车2档原地起步换挡加速时间曲线);xlabel(时间t（s）);ylabel(速度ua（km/h）);2.7matlab程序：（1）%绘制汽车功率平衡图。 clear %汽车参数。ig=5.56 2.769 1.
