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1、1)“汽车驱动力--行驶阻力平衡图”、“汽车行驶加速度曲线”、“汽车加速度倒数曲线”、“汽车爬坡度图”分析如下：利用MATLAB编程如下:ig=[5.56,2.769,1.644,1.00,0.793];%变速器传动比i0=5.83;%主减速器传动比r=0.367;%车轮半径h=0.85;%传动系机械效率cda=2.77;%空气阻力系数*迎风面积m=3880;%汽车总质量Iw1=1.798;%二前论转动惯量Iw2=3.598;%四后轮转动惯量I=0.218;%飞轮转动惯量g=9.8;%重力加速度
2、forj=1:5forn=600:100:4000;ua(j,n)=(0.377*r*n)/(ig(j)*i0);c=n/1000;tq=-19.313+295.27*c-165.44*c.^2+40.874*c.^3-3.8445*c.^4;%发动机转矩Ft(j,n)=tq*ig(j)*i0*h/r;%汽车驱动力f(j,n)=cda*ua(j,n)*ua(j,n)/21.15+494.3;%汽车行驶阻力s(j)=1+(Iw1+Iw2)/(m*r.^2)+(I*ig(j).^2*i0.^2*h)
3、/(m*r.^2);%汽车旋转质量换算系数a(j,n)=(Ft(j,n)-f(j,n))/(s(j)*m)%汽车加速度b(j,n)=1/a(j,n);D(j,n)=asin((Ft(j,n)-f(j,n))/(3800*g));%坡度角i(j,n)=tan(D(j,n))*100%坡度值Pe(j,n)=Ft(j,n)*ua(j,n)/3600%汽车功率endendsubplot(2,2,1)k=600:100:4000plot(ua(1,k),Ft(1,k),ua(2,k),Ft(2,k),ua
4、(3,k),Ft(3,k),ua(4,k),Ft(4,k),...ua(5,k),Ft(5,k),ua(1,k),f(1,k),ua(2,k),f(2,k),ua(5,k),f(5,k));title('汽车驱动力--行驶阻力平衡图')xlabel('ua/(km*h^{-1})');ylabel('F/N');text(26,12000,'Ft1','HorizontalAlignment','right');text(36,6450,'Ft2','HorizontalAlignment','
5、right');text(56,3900,'Ft3','HorizontalAlignment','right');text(66,2500,'Ft4','HorizontalAlignment','right');text(66,1800,'Ft5','HorizontalAlignment','right');text(100,1400,'Ff+Fw','HorizontalAlignment','right');subplot(2,2,2)k=600:100:4000plot(ua(1,k
6、),a(1,k),ua(2,k),a(2,k),ua(3,k),a(3,k),ua(4,k),a(4,k),ua(5,k),a(5,k));title('汽车行驶加速度曲线')xlabel('ua/(km*h^{-1})');ylabel('a/m*s^{-2}');axis([0,120,-0.5,2.5]);text(14,2,'1','HorizontalAlignment','right');text(20,1.2,'2','HorizontalAlignment','right');t
7、ext(30,0.7,'3','HorizontalAlignment','right');text(50,0.5,'4','HorizontalAlignment','right');text(60,0.15,'5','HorizontalAlignment','right');subplot(2,2,3)k=600:100:4000plot(ua(1,k),b(1,k));holdonplot(ua(2,k),b(2,k),ua(3,k),b(3,k),ua(4,k),b(4,k),ua(5
8、,k),b(5,k));title('汽车加速度倒数曲线')xlabel('ua(km/h)');ylabel('1/a');axis([0,100,0,15]);subplot(2,2,4)m=600:100:4000imax=max(i(1,m));plot(ua(1,m),i(1,m));holdonplot(ua(2,m),i(2,m),ua(3,m),i(3,m),ua(4,m),i(4,m),ua(5,m),i(5,m));ua=0:1:12;plot(ua,imax);title(
