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Diffstat (limited to '1052/CH14/EX14.5/145.sce')
-rwxr-xr-x | 1052/CH14/EX14.5/145.sce | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/1052/CH14/EX14.5/145.sce b/1052/CH14/EX14.5/145.sce new file mode 100755 index 000000000..1a87f13a3 --- /dev/null +++ b/1052/CH14/EX14.5/145.sce @@ -0,0 +1,44 @@ +clc;
+//Exampkle 14.5
+//page no 157
+printf("Example 14.5 page no 157\n\n");
+//air is transported through a circular conduit
+MW=28.9//molecular weight of air
+R=10.73//gas constant
+T=500//temperature
+P=14.75//pressure,psia
+//applying ideal gas law for density
+rho=P*MW/(R*T)//density
+rho=0.08//after round off
+meu=3.54e-7//viscosity of air at 40 degF
+//assume flow is laminar
+q=8.33//flow rate ,ft^3/s
+L=800//length of pipe,ft
+P_1=.1//pressure at starting point
+P_2=.01//pressure at delivery point
+D=[(128*meu*L*q)/(%pi*(P_1-P_2)*144)]^(1/4)//diameter
+printf("\n pipe diameter D=%f ft",D);
+//check the flow type
+meu=1.14e-5
+R_e1=4*q*rho/(%pi*D*meu)//reynolds no
+//printf("\n reynolds no R_e=%f ",R_e);
+//from R_e we can conclude that laminar flow is not valid
+P_drop=12.96//pressure drop P_1-P2 in psf
+f=0.005//fanning friction factor
+g_c=32.174
+D=(32*rho*f*L*q^2/(g_c*%pi^2*P_drop))^(0.2)//diamter from new assumption
+//strat the second iteration with the newly calculated D
+k=0.00006/12//roughness factor
+K_r=k/D//relative roughness
+C_f=1.321224
+R_e_n=4*q*rho/(%pi*D*meu)//new reynolds no
+//printf("\n new reynolds no R_e=%f ",R_e);
+f_n=0.0045//new fanning friction factor
+D=[((8*rho*f_n*L*q^2)/(g_c*%pi^2*P_drop))^(0.2)]*C_f//final calculated diameter because last diameter is same with this
+printf("\nD=%f ",D);
+//iteration may now be terminated
+S=%pi*(D^2)/4//cross sectional area of pipe
+v=q/S//flow velocity
+printf("\n flow velocity v=%f ft/s",v);//printing mistake in book in the value of meu in the formula of D is first time that's why this deviation in answer
+
+
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