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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*power(n,2)/1000000+40.874*power(n,3)/1000000000-3.8445*power(n,4)/1000000000000;forig=[5.562.7691.6441.000.793]
2、;Ua=0.377*r*n/ig/i0;Ft=Ttq*ig*i0*eff/r;Ff=m*g*f;Fw=CdA*power(Ua,2)/21.12;Fs=Ff+Fw;plot(Ua,Ft,Ua,Fs);holdon;endtext(15,13000,'F_t_1');text(20,7000,'F_t_2');text(40,4000,'F_t_3');text(55,2500,'F_t_4');text(70,1900,'F_t_5');text(105,2100,'F_f+F_w');xlabel('u_akm/h');ylabel('F_tN');tit
3、le('驱动力-行驶阻力平衡图');[x,y]=ginput(1);disp('汽车的最高车速');disp(x);disp('km/h');Ua=0.377*r*n/ig/i0;Ft=Ttq*5.56*i0*eff/r;Ff=m*g*f;Fw=CdA*power(Ua,2)/21.12;Fs=Ff+Fw;i=atan((Ft-Fs)/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);figure;forig=[5.562.7691
4、.6441.000.793];Ua=0.377*r*n/ig/i0;Ft=Ttq*ig*i0*eff/r;q=1+Iw/(m*r^2)+If*ig^2*i0^2*eff/(m*r^2);Ff=m*g*f;Fw=CdA*power(Ua,2)/21.12;Fs=Ff+Fw;Ac=(Ft-Fs)/q/m;plot(Ua,1./Ac);holdon;endaxis([098010]);text(5,0.5,'1');text(10,1,'2');text(20,1.5,'3');text(30,2.5,'4');text(40,4,'5');title('行驶加速
5、度倒数曲线');xlabel('Ua/(km/h)');ylabel('1/a');figure;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*(n(w)/1000)^4;Ft(w)=Ttq(w)*ig*i0*eff/r;Ff=G*f;Fw(w)=CdA*u
6、(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+1)>=0.377*4000*r/1.00/i0)ig=0.793;endt(w+1)=(w+1)*dt;w=w+1;endplot(t,u);holdonu=70
7、;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);2.7n=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=-19.31
8、3+295.27*n/1000-165.44*pow
