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1、精品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=[5.56,2.76
2、9,1.644,1.00,0.793]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'),gte
3、xt('Ft5'),gtext('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;-可编辑-精品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));dis
4、p('克服最大爬坡度时的附着率');disp(C);%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'
5、);xlabel('Ua/(km/h)');ylabel('1/a');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)-可编辑-精品n(w)=u(w)*ig*i0/0.377/r;Ttq(w)=-19.313+295.27*n(w)/1000-165
6、.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(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;e
7、ndif(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;end-可编辑-精品figure;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
8、');disp(x1);驱动力-行驶阻力平衡图14000Ft112000100008000N/Ft2Ft60004000Ft3Ft4Ff+Fw2000Ft5Umax=99.070020406080100120Ua/(km/h)行驶加速度倒数曲线1098761/a5a51/41/a431/a321/a211/a100102030405060708090Ua/(km/h)-可编辑-精品2挡原地起步加速时间曲线100908070h)60m/k(50u/速40车30201000102025.883040
