资源描述：
《汽车理论课后题matlab程序.doc》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、1.3n=600:1:4000;r=0.367;i0=5.83;eff=0.85;f=0.013;m=3880;g=9.8;G=m*g;CdA=2.77;a=1.947;hg=0.9;L=3.2;Iw1=1.798;Iw2=3.598;Iw=Iw1+Iw2;If=0.218;Ttq=-19.313+295.27*n/1000-165.44*(n/1000).^2+40.874*(n/1000).^3-3.8445*(n/1000).^4;%驱动力行驶阻力平衡图forig=[5.56,2.769,1.644,
2、1.00,0.793]Ua=0.377*r*n/ig/i0;Ft=Ttq*ig*i0*eff/r;plot(Ua,Ft);holdon;endFf=G*f;ua=0:0.1:max(Ua);Fw=CdA*ua.^2/21.15;plot(ua,(Ff+Fw));title('驱动力-行驶阻力平衡图');xlabel('Ua/(km/h)');ylabel('Ft/N');gtext('Ft1'),gtext('Ft2'),gtext('Ft3'),gtext('Ft4'),gtext('Ft5'),gtex
3、t('Ff+Fw')[x,y]=ginput(1);disp('汽车的最高车速');disp(x);disp('km/h');%最大爬坡度及最大爬坡度时的附着率Ua=0.377*r*n/5.56/i0;Ft=Ttq*5.56*i0*eff/r;Fw=CdA*Ua.^2/21.15;i=tan(asin((Ft-(Ff+Fw))/G));disp('汽车的最大爬坡度');disp(max(i));C=max(i)/(a/L+hg/L*max(i));disp('克服最大爬坡度时的附着率');disp(C);%
4、加速度倒数曲线figure;forig=[5.56,2.769,1.644,1.00,0.793]Ua=0.377*r*n/ig/i0;q=1+Iw/(m*r^2)+If*ig^2*i0^2*eff/(m*r^2);Ft=Ttq*ig*i0*eff/r;Fw=CdA*Ua.^2/21.15;as=(Ft-(Ff+Fw))/q/m;plot(Ua,1./as);holdon;endaxis([098010]);title('行驶加速度倒数曲线');xlabel('Ua/(km/h)');ylabel('1/a
5、');gtext('1/a1'),gtext('1/a2'),gtext('1/a3'),gtext('1/a4'),gtext('1/a5');%加速时间曲线u(1)=0.377*r*600/i0/2.769;dt=0.01;w=1;t(1)=0;ig=2.769;while(u(w)<99.08)n(w)=u(w)*ig*i0/0.377/r;Ttq(w)=-19.313+295.27*n(w)/1000-165.44*(n(w)/1000)^2+40.874*(n(w)/1000)^3-3.8445*
6、(n(w)/1000)^4;Ft(w)=Ttq(w)*ig*i0*eff/r;Ff=G*f;Fw(w)=CdA*u(w)^2/21.15;q=1+Iw/(m*r^2)+If*ig^2*i0^2*eff/(m*r^2);a(w)=3.6*(Ft(w)-(Ff+Fw(w)))/q/m;u(w+1)=u(w)+a(w)*dt;if(u(w+1)>=0.377*4000*r/2.769/i0)ig=1.644;endif(u(w+1)>=0.377*4000*r/1.644/i0)ig=1.00;endif(u(w
7、+1)>=0.377*4000*r/1.00/i0)ig=0.793;endt(w+1)=(w+1)*dt;w=w+1;endfigure;plot(t,u);axis([0600100]);title('2挡原地起步加速时间曲线');xlabel('时间t/s'),ylabel('车速u/(km/h)');[x1,y1]=ginput(1);disp('加速到70km/h的时间');disp(x1);1.8Iw1=2.25;Iw2=2.25;Iw=Iw1+Iw2;If=0.25;m=1600;g=9.8;
8、G=m*g;Ttqmax=140;i1=3.85;i0=4.08;eff=0.9;r=0.3;hg=0.63;b=1.25;L=2.7;q=1+Iw/(m*r^2)+If*i1^2*i0^2*eff/(m*r^2);Ft=Ttqmax*i1*i0*eff/r;a=Ft/q/m;q=a/g;C1=q/(b/L-hg/L*q);if(C1>0.6)disp('发动机转矩不能充分发挥');elsedisp('发动机转矩
