From 47aed0c794519712fe683d430de7a2e20d9eb654 Mon Sep 17 00:00:00 2001
From: Nilesh <nileshgsawant@live.com>
Date: Tue, 28 May 2013 15:24:29 +0530
Subject: [PATCH] Create 1-D Nozzle

This code solves a 1-D nozzle Convergent Divergent Nozzle using finite difference method.
---
 1-D Nozzle | 136 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 136 insertions(+)
 create mode 100644 1-D Nozzle

diff --git a/1-D Nozzle b/1-D Nozzle
new file mode 100644
index 0000000..3cf038b
--- /dev/null
+++ b/1-D Nozzle	
@@ -0,0 +1,136 @@
+#This code solves the flow in a 1D convergent divergent nozzle using
+#finite difference method
+
+import numpy as np; import matplotlib.pyplot as plt
+print('All Modules Imported \n\n\n')
+
+grid=np.linspace(0,3,31)    #grid set
+
+A=1 + 2.2 * (grid-1.5)**2   #Area
+Ro=1- 0.3146*grid           #Density
+T = 1 - 0.2314*grid         #Temperature
+V= (0.1 + 1.09*grid)*np.sqrt(T)  #Velocity
+M=V/np.sqrt(T)
+Mdata=[M[15]]
+Mdataex=[M[30]]
+Mdatain=[M[0]]
+print('V is ',V)
+
+
+t=0
+itr=1
+
+while(1):
+
+ delt=(0.5*(0.1/(np.sqrt(T)+V))).min()
+
+
+ i=1
+
+ RoDdata=[0]
+ VDdata=[0]
+ TDdata=[0]
+
+
+ while i<30:
+  RoD=(((-Ro[i]*((V[i+1]-V[i])/0.1)))-((Ro[i]*V[i]*((np.log(A[i+1])-np.log(A[i]))/0.1)))-((V[i]*((Ro[i+1]-Ro[i])/0.1))))
+  RoDdata.append(RoD)
+  VD=(-V[i]*((V[i+1]-V[i])/0.1)) - (((T[i+1]-T[i])/0.14)+((T[i]*Ro[i+1]-T[i]*Ro[i])/(0.14*Ro[i])))
+  VDdata.append(VD)
+  TD=-V[i]*((T[i+1]-T[i])/0.1)-((1.4-1)*T[i])*( ((V[i+1]-V[i])/0.1) + V[i]*((np.log(A[i+1])-np.log(A[i]))/0.1))
+  TDdata.append(TD)
+  i=i+1
+
+
+ RoDdata.append(0)
+ VDdata.append(0)
+ TDdata.append(0)
+ 
+
+ Robar=Ro + np.asarray(RoDdata) * delt
+ Vbar=V + np.asarray(VDdata) * delt
+ Tbar=T + np.asarray(TDdata) * delt
+
+
+ i=1
+
+ RoDdata2=[0]
+ VDdata2=[0]
+ TDdata2=[0]
+
+
+ while i<30:
+  RoD=(((-Robar[i]*((Vbar[i]-Vbar[i-1])/0.1)))-((Robar[i]*Vbar[i]*((np.log(A[i])-np.log(A[i-1]))/0.1)))-((Vbar[i]*((Robar[i]-Robar[i-1])/0.1))))
+  RoDdata2.append(RoD)
+  VD=(-Vbar[i]*((Vbar[i]-Vbar[i-1])/0.1)) - (((Tbar[i]-Tbar[i-1])/0.14)+((Tbar[i]*Robar[i]-Tbar[i]*Robar[i-1])/(0.14*Robar[i])))
+  VDdata2.append(VD)
+  TD=-Vbar[i]*((Tbar[i]-Tbar[i-1])/0.1)-((1.4-1)*Tbar[i])*( ((Vbar[i]-Vbar[i-1])/0.1) + Vbar[i]*((np.log(A[i])-np.log(A[i-1]))/0.1))
+  TDdata2.append(TD)
+  i=i+1
+
+
+ RoDdata2.append(0)
+ VDdata2.append(0)
+ TDdata2.append(0)
+
+
+
+ RoDavg=0.5 * (np.asarray(RoDdata) + np.asarray(RoDdata2))
+ VDavg=0.5 * (np.asarray(VDdata) + np.asarray(VDdata2))
+ TDavg=0.5 * (np.asarray(TDdata) + np.asarray(TDdata2))
+
+
+
+ Ro=Ro + np.asarray(RoDavg) * delt
+ V=V + np.asarray(VDavg) * delt
+ T=T + np.asarray(TDavg) * delt
+
+
+
+ V[0]= 2*V[1] - V[2]
+ Ro[0]= 2*Ro[1] - Ro[2]
+ T[0]= 2*T[1] - T[2]
+
+ V[30]= 2*V[29] - V[28]
+ Ro[30]= 2*Ro[29] - Ro[28]
+ T[30]= 2*T[29] - T[28]
+
+ P = Ro * T
+ 
+ M=V/np.sqrt(T)
+ 
+ Mdata.append(M[15])
+ Mdataex.append(M[30])
+ Mdatain.append(M[0])
+ 
+
+
+ t= t + delt
+
+ itr=itr+1
+ print('Iteration number : ',itr)
+
+ if (np.absolute(Mdata[-1]-Mdata[-2])) < 0.0000001:
+  break
+ 
+    
+
+print('\n\n P is ',P)
+
+print('\n\n mach no. is ',M)
+
+print('\n\n V, Ro & T are ',V,'\n\n',  Ro,'\n\n', T)
+
+print('\n\n Iterations required = ',itr-1, '\n\n Time = ',t, ' seconds')
+
+plt.plot(np.arange(itr),Mdata,'-',np.arange(itr),Mdataex,'-',np.arange(itr),Mdatain,'-')
+plt.xlabel('X coordinate -->  Iterations')
+plt.ylabel('Y coordinate -->  Mach Number')
+plt.title('Variation in Mach number')
+plt.legend(['Throat','Exit','Inlet'],bbox_to_anchor=(0,0),loc=4)
+plt.show()
+
+
+
+
+