From b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b Mon Sep 17 00:00:00 2001
From: priyanka
Date: Wed, 24 Jun 2015 15:03:17 +0530
Subject: initial commit / add all books

---
 172/CH8/EX8.1/ex1.sce   | 15 +++++++++++++++
 172/CH8/EX8.10/ex10.sce | 17 +++++++++++++++++
 172/CH8/EX8.2/ex2.sce   | 16 ++++++++++++++++
 172/CH8/EX8.3/ex3.sce   | 11 +++++++++++
 172/CH8/EX8.4/ex4.sce   | 20 ++++++++++++++++++++
 172/CH8/EX8.5/ex5.sce   | 16 ++++++++++++++++
 172/CH8/EX8.6/ex6.sce   | 17 +++++++++++++++++
 172/CH8/EX8.7/ex7.sce   | 15 +++++++++++++++
 172/CH8/EX8.8/ex8.sce   | 13 +++++++++++++
 172/CH8/EX8.9/ex9.sce   |  8 ++++++++
 10 files changed, 148 insertions(+)
 create mode 100755 172/CH8/EX8.1/ex1.sce
 create mode 100755 172/CH8/EX8.10/ex10.sce
 create mode 100755 172/CH8/EX8.2/ex2.sce
 create mode 100755 172/CH8/EX8.3/ex3.sce
 create mode 100755 172/CH8/EX8.4/ex4.sce
 create mode 100755 172/CH8/EX8.5/ex5.sce
 create mode 100755 172/CH8/EX8.6/ex6.sce
 create mode 100755 172/CH8/EX8.7/ex7.sce
 create mode 100755 172/CH8/EX8.8/ex8.sce
 create mode 100755 172/CH8/EX8.9/ex9.sce

(limited to '172/CH8')

diff --git a/172/CH8/EX8.1/ex1.sce b/172/CH8/EX8.1/ex1.sce
new file mode 100755
index 000000000..b5c2504e1
--- /dev/null
+++ b/172/CH8/EX8.1/ex1.sce
@@ -0,0 +1,15 @@
+//example 1
+//coefficient of performance of refrigerator
+clear
+clc
+Th=60 //temperature at which heat is rejected from R-134a
+Tl=0 //temperature at which heat is absorbed into the R-134a 
+s1=1.7262 //specific entropy at 0 Celsius
+s2=s1 //process of state change from 1-2 is isentropic 
+s3=1.2857 //specific entropy at 60 celsius
+s4=s3 //process of state change from 3-4 is isentropic
+disp('if Pressure is 1400 kPa,then s=1.7360 kJ/kg-K and if P=1600 kPa,then s=1.7135 kJ/kg-K.Therefore')
+P2=1400+(1600-1400)*(1.7262-1.736)/(1.7135-1.736) //pressure after compression in kPa
+B=(Th+273)/(Th-Tl) //coefficient of performance of refrigerator
+printf(" \n hence,pressure after compression is P2=%.3f kPa.\n",P2) 
+printf("\n and coefficient of performance of refrigerator is B=%.3f .\n",B)
\ No newline at end of file
diff --git a/172/CH8/EX8.10/ex10.sce b/172/CH8/EX8.10/ex10.sce
new file mode 100755
index 000000000..018a8b3ce
--- /dev/null
+++ b/172/CH8/EX8.10/ex10.sce
@@ -0,0 +1,17 @@
+//example 10
+//Determiining the entropy generated
+clear
+clc
+B=4 //COP of air conditioner
+W=10 //power input of air conditioner in kW
+Qh=B*W //in kW
+Ql=Qh-W //in kW
+Thigh=323 //in Kelvin
+Tlow=263 //in Kelvin
+SgenHP=(Qh*1000/Thigh)-(Ql*1000/Tlow) //in W/K
+Tl=281 // in K
+Th=294 //in K
+SgenCV1=Ql*1000/Tlow-Ql*1000/Tl //in W/K
+SgenCV2=Qh*1000/Th-Qh*1000/Thigh //in W/K
+SgenTOT=SgenCV1+SgenCV2+SgenHP //in W/K
+printf(" \n Hence,Total entropy generated is SgenTOT=%.1f W/K. \n",SgenTOT)
\ No newline at end of file
diff --git a/172/CH8/EX8.2/ex2.sce b/172/CH8/EX8.2/ex2.sce
new file mode 100755
index 000000000..36431002e
--- /dev/null
+++ b/172/CH8/EX8.2/ex2.sce
@@ -0,0 +1,16 @@
+//example 2 
+//heat transfer in a given process
+clear
+clc
+u1=87.94 //specific internal energy of R-12 at state 1 in kJ/kg
+u2=276.44 //specific internal energy of R-12 at state 2 in kJ/kg
+s1=0.3357 //specific entropy at state 1 in kJ/kg-K
+s2=1.2108 //specific entropy at state 2 in kJ/kg-K
+V=0.001 //volume of saturated liquid in m^3
+v1=0.000923 //specific volume in m^3/kg
+m=V/v1 //mass of saturated liquid in kg
+T=20 //temperature of liquid in celsius
+Q12=m*(T+273.15)*(s2-s1) //heat transfer in kJ to accomplish the process
+W12=m*(u1-u2)+Q12 //work required to accomplish the process
+printf(" \n hence,work required to accomplish the process is W12=%.1f kJ.\n",W12)
+printf(" \n and heat transfer is Q12=%.1f kJ.\n",Q12)
\ No newline at end of file
diff --git a/172/CH8/EX8.3/ex3.sce b/172/CH8/EX8.3/ex3.sce
new file mode 100755
index 000000000..15ab12073
--- /dev/null
+++ b/172/CH8/EX8.3/ex3.sce
@@ -0,0 +1,11 @@
+//example 3
+//entropy change
+clear
+clc
+C=4.184 // specific heat of water in kJ/kg-K
+T1=20 //initial temperature of water in celsius
+T2=90 //final temperature of water in celsius
+dS1=C*log((T2+273.2)/(T1+273.2)) //change in entropy in kJ/kg-K
+dS2=1.1925-0.2966 //in kJ/kg-K using steam tables
+printf("\n hence,change in entropy assuming constant specific heat is dS1=%.4f kJ/kg-K.\n",dS1)
+printf("\n using steam table is dS2=%.4f kJ/kg-K.\n",dS2) 
\ No newline at end of file
diff --git a/172/CH8/EX8.4/ex4.sce b/172/CH8/EX8.4/ex4.sce
new file mode 100755
index 000000000..9399182cc
--- /dev/null
+++ b/172/CH8/EX8.4/ex4.sce
@@ -0,0 +1,20 @@
+//example 4
+//entropy change with different assumptions
+clear
+clc
+T1=300 //initial temperature in kelvins
+T2=1500 //final temperature in kelvins
+P1=200 //initial pressure in kPa
+P2=150 //final pressure in kPa
+R=0.2598 // in kJ/kg-K
+Cp=0.922 //specific heat in kJ/kg-K at constant pressure
+dsT2=8.0649 //in kJ/kg-K
+dsT1=6.4168 //in kJ/kg-K
+dS1=dsT2-dsT1-R*log(P2/P1) //entropy change calculated using ideal gas tables
+dS2=integrate('0.88/x-0.0001+0.54*x-0.33*x^2','x',0.3,1.5)-R*log(P2/P1) //entropy change calculated using empirical equation 
+dS3=Cp*log(T2/T1)-R*log(P2/P1) //entropy change assuming constant specific heat in kJ/kg-K
+dS4=1.0767*log(T2/T1)+0.0747 //entropy change assuming specific heat is constant at its value at 990K
+printf("\n hence,change in entropy using ideal gas tables is dS1=%.4f kJ/kg-K.\n",dS1)
+printf("\n hence,change in entropy using empirical equation is dS2=%.4f kJ/kg-K.\n",dS2)
+printf("\n hence,change in entropy using the value of specific heat at 300K is dS3=%.4f kJ/kg-K.\n",dS3)
+printf("\n hence,change in entropy assuming specific heat is constant at its value at 900K is dS4=%.4f kJ/kg-K.\n",dS4)
\ No newline at end of file
diff --git a/172/CH8/EX8.5/ex5.sce b/172/CH8/EX8.5/ex5.sce
new file mode 100755
index 000000000..f23cb3ac9
--- /dev/null
+++ b/172/CH8/EX8.5/ex5.sce
@@ -0,0 +1,16 @@
+//example 5
+//entropy change
+clear
+clc
+Cp=1.004 //specific heat at constant pressure in kJ/kg-K
+R=0.287 //gas constant in kJ/kg-K
+P1=400 //initial pressure in kPa
+P2=300 //final pressure in kPa
+T1=300 //initial temperature in K
+T2=600 //final temperature in K
+dS1=Cp*log(T2/T1)-R*log(P2/P1) //entropy change assuming constant specific heat
+s1=6.8693 //specific entropy at T1
+s2=7.5764 //specific entropy at T2
+dS2=s2-s1-R*log(P2/P1) //entropy change assuming variable specific heat
+printf("\n hence,entropy change assuming constant specific heat is dS1=%.4f kJ/kg-K.\n",dS1)
+printf("\n and assuming variable specific heat is dS2=%.4f kJ/kg-K.\n",dS2)
\ No newline at end of file
diff --git a/172/CH8/EX8.6/ex6.sce b/172/CH8/EX8.6/ex6.sce
new file mode 100755
index 000000000..ebfbe454d
--- /dev/null
+++ b/172/CH8/EX8.6/ex6.sce
@@ -0,0 +1,17 @@
+//example 6
+//work done by air
+clear
+clc
+T1=600 //initial temperature of air in K
+P1=400 //intial pressure of air in kPa
+P2=150 //final pressure in kPa
+u1=435.10 //specific internal energy at temperature T1 in kJ/kg
+sT1=7.5764 //specific entropy at temperature T1 in kJ/kg-K
+R=0.287 //gas constant in kJ/kg-K
+ds=0
+sT2=ds+sT1+R*log(P2/P1) //specific entropy at temperature T2 in kJ/kg-K
+disp('we know the values of s and P for state 2.So,in order to fully determine the state,we will use steam table')
+T2=457 //final temperature in K
+u2=328.14 //specific internal energy at temperature T2 in kJ/kg
+w=u1-u2 //work done by air in kJ/kg
+printf("\n hence,work done by air is w=%.2f kJ/kg.\n",w)
\ No newline at end of file
diff --git a/172/CH8/EX8.7/ex7.sce b/172/CH8/EX8.7/ex7.sce
new file mode 100755
index 000000000..18fd02c90
--- /dev/null
+++ b/172/CH8/EX8.7/ex7.sce
@@ -0,0 +1,15 @@
+//example 7
+//work and heat transfer
+clear
+clc
+P2=500  //final pressure in cylinder in kPa
+P1=100 //initial pressure in cylinder in kPa
+T1=20+273.2 //initial temperature inside cylinder in Kelvins
+n=1.3 
+T2=(T1)*(P2/P1)^((n-1)/n) //final temperature inside cylinder in K
+R=0.2968 //gas constant in kJ/kg-K
+w12=R*(T2-T1)/(1-n) //work in kJ/kg
+Cvo=0.745 //specific heat at constant volume in kJ/kg-K
+q12=Cvo*(T2-T1)+w12 //heat transfer in kJ/kg
+printf(" \n hence,work done is w12=%.1f kJ/kg.\n",w12)
+printf("\n and heat transfer are q12=%.1f kJ/kg.\n",q12)
\ No newline at end of file
diff --git a/172/CH8/EX8.8/ex8.sce b/172/CH8/EX8.8/ex8.sce
new file mode 100755
index 000000000..d5a5dbad8
--- /dev/null
+++ b/172/CH8/EX8.8/ex8.sce
@@ -0,0 +1,13 @@
+//example 3
+//calculating increase in entropy
+clear
+clc
+m=1 //mass of saturated water vapour
+sfg=6.0480 //in kJ/K
+T=25 //temperature of surrounding air in celsius
+dScm=-m*sfg //change in entropy of control mass in kJ/K
+hfg=2257.0 //in kJ/kg
+Qtosurroundings=m*hfg //heat transferred to surroundings in kJ
+dSsurroundings=Qtosurroundings/(T+273.15) //in kJ/K
+dSnet=dScm+dSsurroundings //net increase in entropy in kJ/K
+printf(" hence,net increase in entropy of water plus surroundings is dSnet=%.4f kJ/K.\n",dSnet)  
\ No newline at end of file
diff --git a/172/CH8/EX8.9/ex9.sce b/172/CH8/EX8.9/ex9.sce
new file mode 100755
index 000000000..4065db4e6
--- /dev/null
+++ b/172/CH8/EX8.9/ex9.sce
@@ -0,0 +1,8 @@
+//example 9
+//entropy generation
+clear
+clc
+Qout=1 //value of heat flux generated by 1kW of electric power
+T=600 //temperature of hot wire surface in K
+Sgen=Qout/T //entropy generation in kW/K
+printf(" \n hence,entropy generation is Sgen=%.5f kW/K.\n",Sgen)
\ No newline at end of file
-- 
cgit