求大佬解答,这是从comsol里面导出的压力数据,模拟阻抗管测反射系数和吸声系数
clear all
clc
A=readmatrix('Point_30mm.txt');
B=readmatrix('Point_20mm.txt');
x=0.01;
l=0.03;
for n=1:198
f=20+5*n
p1=A(n,1)
p2=B(n,1)
h12=p2./p1
k=2*pi*f/343
hi=exp(-1i*k*x)
hr=exp(1i*k*x)
c=(h12-hi)/(hr/h12)
r=c*exp(1i*2*k*l)
R=abs(r)
a=1-R
figure(1)
plot (f,a,'r-','LineWidth',1);
xlim([25 1000])
end
figure(1)
f=25:5:1000;
A=a(:,1);
plot (f,A,'r-','LineWidth',1);
xlim([25 1000])
clear all
clc
A=readmatrix('Point_30mm.txt');
B=readmatrix('Point_20mm.txt');
x=0.01;
l=0.03;
for n=1:198
f=20+5*n
p1=A(n,1)
p2=B(n,1)
h12=p2./p1
k=2*pi*f/343
hi=exp(-1i*k*x)
hr=exp(1i*k*x)
c=(h12-hi)/(hr/h12)
r=c*exp(1i*2*k*l)
R=abs(r)
a=1-R
figure(1)
plot (f,a,'r-','LineWidth',1);
xlim([25 1000])
end
figure(1)
f=25:5:1000;
A=a(:,1);
plot (f,A,'r-','LineWidth',1);
xlim([25 1000])