1.3
n=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
for ig=[5.56,2.769,1.644,1.00,0.793] Ua=0.377*r*n/ig/i0; Ft=Ttq*ig*i0*eff/r; plot(Ua,Ft); hold on; end Ff=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'),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; 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); %加速度倒数曲线 figure;
for ig=[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); hold on; end
axis([0 98 0 10]);
title('行驶加速度倒数曲线');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)
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(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; end
if(u(w+1)>=0.377*4000*r/1.644/i0) ig=1.00; end
if(u(w+1)>=0.377*4000*r/1.00/i0) ig=0.793; end
t(w+1)=(w+1)*dt; w=w+1; end
figure;plot(t,u);axis([0 60 0 100]);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);
驱动力-行驶阻力平衡图1400012000100008000Ft1Ft/NFt26000400020000Ft3Ft4Ft5Umax=99.07100Ff+Fw0204060Ua/(km/h)80120
行驶加速度倒数曲线1098761/a51/a54321001/a31/a21/a1102030405060Ua/(km/h)7080901/a4
2挡原地起步加速时间曲线100908070车速u/(km/h)60504030201000102025.8830时间t/s405060
1.8
Iw1=2.25; Iw2=2.25; Iw=Iw1+Iw2; If=0.25; m=1600; g=9.8;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;