diff options
Diffstat (limited to '629/CH14/EX14.7')
-rw-r--r-- | 629/CH14/EX14.7/ex14_7.txt | 5 | ||||
-rw-r--r-- | 629/CH14/EX14.7/example14_7.sce | 35 |
2 files changed, 40 insertions, 0 deletions
diff --git a/629/CH14/EX14.7/ex14_7.txt b/629/CH14/EX14.7/ex14_7.txt new file mode 100644 index 000000000..064e963a7 --- /dev/null +++ b/629/CH14/EX14.7/ex14_7.txt @@ -0,0 +1,5 @@ +
+The net positive suction head = 26.1 ft.
+
+The traditional suction specific speed, Nss = 4538.
+
\ No newline at end of file diff --git a/629/CH14/EX14.7/example14_7.sce b/629/CH14/EX14.7/example14_7.sce new file mode 100644 index 000000000..566e74ba5 --- /dev/null +++ b/629/CH14/EX14.7/example14_7.sce @@ -0,0 +1,35 @@ +clear
+clc
+//Example 14.7 NET POSITIVE SUCTION HEAD
+//To find Approx Value
+function [A]= approx (V,n)
+ A= round(V*10^n)/10^n; //V-Value, n-to what place
+ funcprot (0)
+endfunction
+g=32.2;//[ft/s^2]
+Gamma=62.2; //[lbf/ft^3]
+d=8/12; //diameter[ft]
+A=%pi*d^2/4 //area[ft^2]
+Q=2; //discharge[cfs]
+V2=approx(Q/A,2) //[ft/s]
+p1=14.7; //[lbf/in^2]
+//Pressure head at reservoir,hr
+hr=approx(p1*144/Gamma,0) //[ft]
+//Energy equation, (p1/gamma)+(V1^2/2g)+z1=(p2/gamma)+(V2^2/2g)+z2+hL
+//V1=0,z1=0
+z2=6; //[m]
+Ce=0.1; //entrance loss coefficient
+Cb=0.2; //bend loss coefficient
+hL=(Ce+Cb)*V2^2/(2*g)
+//Head at pump entrance, he=p2/Gamma
+he=approx(hr-z2-V2^2/(2*g)-hL,1) //[ft]
+pvap=0.506; //vapor pressure[psi]
+hp=pvap*144/Gamma //[ft]
+//Net positive suction head
+NPSH=he-hp //[ft]
+printf("\nThe net positive suction head = %.1f ft.\n",NPSH)
+//Traditional suction specific speed
+N=1750; //in rpm
+//1cfs=449 gpm
+Nss=N*(Q*449)^(1/2)/NPSH^(3/4)
+printf("\nThe traditional suction specific speed, Nss = %.f.\n",Nss)
\ No newline at end of file |