2016年全国数学建模A题matlab代码.rar

%直接搜索法求解问题1，搜索h for h=0:0.01:2 p=1.025e3;%海水密度 H=18;%水深 W=1200;%重物球质量 v_f=12;%风速 %v_f=24; g=9.8;%重力加速度 d_fu=2;%浮标直径 h_fu=2;%浮标高度 T1=p*g*pi*d_fu^2*h/4;%浮标浮力 S1=(h_fu-h)*d_fu;%风面投影 F0=0.625*S1*v_f^2;%风力 G1=1000*g;%浮标重力; %% %浮标段计算 F2=sqrt(F0^2+(T1-G1)^2); beta1=atan(5*(h_fu-h)*d_fu*v_f^2/(8*G1+2*p*g*pi*d_fu^2*h)); %% %钢管段计算 d_g=5e-2; h_g=1; m_g=10; T2=p*g*pi*d_g^2*h_g/4;%钢管浮力 G2=m_g*g;%钢管重力 beta=zeros(1,5); F=zeros(1,5); theta=zeros(1,5);%实际只用四个 beta(1)=beta1; F(1)=F2; for i=2:5 beta(i)=atan(F(i-1)*sin(beta(i-1))/(T2+F(i-1)*cos(beta(i-1))-G2)); F(i)=F(i-1)*sin(beta(i))/(sin(atan(F(i-1)*sin(beta(i-1))/(T2+F(i-1)*cos(beta(i-1))-G2)))); theta(i)=atan(F(i-1)*sin(beta(i-1))/(0.25*(T2-G2)+F(i-1)*cos(beta(i-1)))); end %% %钢桶段 d_t=0.3;%钢桶直径 h_t=1;%钢桶高度 m_t=100;%钢桶质量 p2=7.8e3;%重物球密度 T3=p*g*pi*d_t^2*h_t/4;%钢桶浮力 G3=m_t*g;%钢桶重力 G4=W*g;%重物球重力 T4=p*G4/p2;%重物球浮力 beta6=atan(F(5)*sin(beta(5))/(F(5)*cos(beta(5))+T3+T4-G3-G4)); F6=F(5)*sin(beta(5))/(sin(atan(F(5)*sin(beta(5))/(F(5)*cos(beta(5))+T3+T4-G3-G4)))); theta6=atan(F(5)*sin(beta(5))/(0.5*(T4-G4)+F(5)*cos(beta(5)))); %% %锚链段 l_yuan=22.05; k=7;%线密度 kk=k*(1-p/p2);%修正后的线密度（考虑浮力） F7=F6*sin(beta6); alpha=atan((F6*cos(beta6)-l_yuan*kk*g)/(F6*sin(beta6))); if alpha>0 fprintf('alpha为正'); l_m=l_yuan; l_ground=0; if rad2deg(alpha)>15 fprintf('alpha太大了'); else fprintf('alpha满足'); end else fprintf('alpha为负'); l_m=F6*cos(beta6)/(kk*g); alpha=0; l_ground=l_yuan-l_m;%海平面上长度 end syms x m y=F7/(kk*g)*cosh(kk*g*x/F7+asinh(tan(alpha)))-F7/(kk*g)*cosh(asinh(tan(alpha))); y1=sqrt(1+(diff(y,x))^2); mff=@(mm)myfun(y1,x,mm,l_m); so_x=solve(mff); so_y=F7/(k*g)*cosh(k*g*so_x/F7+asinh(tan(alpha)))-F7/(k*g)*cosh(asinh(tan(alpha))); %% %结果检验和指标计算 H_jisuan=so_y+h_t*cos(theta6)+h_g*cos(theta(5))+h_g*cos(theta(4))+h_g*cos(theta(3))+h_g*cos(theta(2))+h; dis=l_ground+so_x+h_t*sin(theta6)+h_g*sin(theta(5))+h_g*sin(theta(4))+h_g*sin(theta(3))+h_g*sin(theta(2))+0.5*d_fu; area=pi*dis^2; if abs(H_jisuan-h)<0.01 fprintf('吃水深度%5.3f米 游动区域%5.3f平方米 钢桶倾角%5.3f° 锚链倾角%5.3f° 总深度%5.3f米\n',h,area,rad2deg(theta6),rad2deg(alpha),H_jisuan); break; end end