www.pudn.com > pinsanquxian.rar > lames2.m, change:2004-08-06,size:764b


%求解Lame波对称部分的基本模态So后的III模态 
format long 
syms c;   %定义速度c为符号函数 
kh=11.5    %k为波数,h为总的板厚 
cd=5790;cs=3200; %cd为纵波波速,cs为横波波速 
y1=-4*tan(kh/2*((c/cd)^2-1)^(1/2))*((c/cd)^2-1)^(1/2)*((c/cs)^2-1)^(1/2); 
y2=(2-(c/cs)^2)^2*tan(kh/2*((c/cs)^2-1)^(1/2)); 
ezplot(y1,[5500,6200]); %作图求解 
hold on 
grid on 
ezplot(y2,[5500,6200]); 
[xx,yy]=ginput(4); 
[x(1),fval,exitflag]=fzero(inline(y1-y2),xx(1),[]); 
[x(2),fval,exitflag]=fzero(inline(y1-y2),xx(2),[]); 
[x(3),fval,exitflag]=fzero(inline(y1-y2),xx(3),[]); 
[x(4),fval,exitflag]=fzero(inline(y1-y2),xx(4),[]); 
for i=1:1:4 
c=x(i) 
y1=-4*tan(kh/2*((c/cd)^2-1)^(1/2))*((c/cd)^2-1)^(1/2)*((c/cs)^2-1)^(1/2); 
y2=(2-(c/cs)^2)^2*tan(kh/2*((c/cs)^2-1)^(1/2)); 
e(i)=y1-y2; 
end