1 files changed, 23 insertions, 0 deletions
diff --git a/1752/CH4/EX4.4/exa_4_4.sce b/1752/CH4/EX4.4/exa_4_4.sce
new file mode 100755
index 000000000..2a921d740
--- /dev/null
+++ b/1752/CH4/EX4.4/exa_4_4.sce
@@ -0,0 +1,23 @@
+//Exa 4.4
+clc;
+clear;
+close;
+//given data
+k=8;// in W/mK
+alpha=4*10^-6;// in m^2/s
+h=50;// in W/m^2K
+D=6*10^-3;// in m
+R=D/2;
+T=0.5;// where T = (t-t_infinite)/(t_i-t_infinite)
+//l_s= V/A = R/3
+l_s= R/2;// in m
+Bi= h*l_s/k;
+// since Bi < 0.1 , hence lumped heat capacity analysis can be applied
+// toh= rho*V*C/(h*A) = rho*C*l_s/h = k*l_s/(h*alpha)
+toh=  k*l_s/(h*alpha);// in seconds
+disp(toh,"time constant in seconds");
+// It is given that (t-t_infinite)/(t_i-t_infinite) = 0.5 =  %e^(-h*A*c /(rho*V*C)) = %e^(-h*c/(rho*l_s*C)) = %e^(-h*alpha*c/(l_s))
+// or (t-t_infinite)/(t_i-t_infinite) = %e^(-h*alpha*c/(l_s);
+c= -log(T)*l_s/(h*alpha);// in sec
+disp(c,"The time required to temperature change to reach half of its initial value in seconds");
+