summaryrefslogtreecommitdiff
path: root/965/CH9
diff options
context:
space:
mode:
Diffstat (limited to '965/CH9')
-rw-r--r--965/CH9/EX9.1/1.sci16
-rw-r--r--965/CH9/EX9.10/10.sci17
-rw-r--r--965/CH9/EX9.11/11.sci18
-rw-r--r--965/CH9/EX9.12/12.sci20
-rw-r--r--965/CH9/EX9.13/13.sci25
-rw-r--r--965/CH9/EX9.14/14.sci20
-rw-r--r--965/CH9/EX9.15/15.sci18
-rw-r--r--965/CH9/EX9.16/16.sci19
-rw-r--r--965/CH9/EX9.17/17.sci32
-rw-r--r--965/CH9/EX9.18/18.sci22
-rw-r--r--965/CH9/EX9.19/19.sci20
-rw-r--r--965/CH9/EX9.2/2.sci13
-rw-r--r--965/CH9/EX9.20/20.sci28
-rw-r--r--965/CH9/EX9.3/3.sci16
-rw-r--r--965/CH9/EX9.4/4.sci20
-rw-r--r--965/CH9/EX9.5/5.sci25
-rw-r--r--965/CH9/EX9.6/6.sci21
-rw-r--r--965/CH9/EX9.7/7.sci15
-rw-r--r--965/CH9/EX9.8/8.sci16
-rw-r--r--965/CH9/EX9.9/9.sci20
20 files changed, 401 insertions, 0 deletions
diff --git a/965/CH9/EX9.1/1.sci b/965/CH9/EX9.1/1.sci
new file mode 100644
index 000000000..0081c4219
--- /dev/null
+++ b/965/CH9/EX9.1/1.sci
@@ -0,0 +1,16 @@
+clc;
+clear all;
+disp("The heat flux")
+d=1.2/1000;//m diameter of wire
+L=0.2;//m length of wire
+p=7;// bar
+I=135;// Amp
+V=2.18;//V
+ts=200;// degree C
+A=%pi*d*L;//m^2
+tsat=164.97;// degree C corresponding to 7 bar
+Q=V*I;//W
+flux=Q/A;// W/m^2 heat flux
+disp("W/m^2",flux,"the heat flux =")
+h=flux/(ts-tsat);
+disp("W/m^2.C",h,"boiling heat transfer coefficient =")
diff --git a/965/CH9/EX9.10/10.sci b/965/CH9/EX9.10/10.sci
new file mode 100644
index 000000000..d27c82347
--- /dev/null
+++ b/965/CH9/EX9.10/10.sci
@@ -0,0 +1,17 @@
+clc;
+clear all;
+disp("Thickness of film")
+L=0.4;//m
+tsat=100;// degree C
+hfg=2257*1000;// J/kg
+ts=90;// degree C
+rhol=965.3;// kg/m^3
+k=0.68;// W/m.C
+mu=3.153*10^(-4);// Ns/m^2
+g=9.81;// m/s^2
+del=(4*k*mu*(tsat-ts)*L/(g*hfg*rhol^2))^0.25;// m
+disp("mm",del*1000,"Thickness of film at bottom edge of the fin ")
+h=4*k/(3*del);
+disp("W/m^2.C",h,"Overall heat transfer coefficient ")
+Q=1.2*h*(tsat-ts)*L;
+disp("W",Q,"heat transfer rate wuth McAdams correction =")
diff --git a/965/CH9/EX9.11/11.sci b/965/CH9/EX9.11/11.sci
new file mode 100644
index 000000000..8de29035c
--- /dev/null
+++ b/965/CH9/EX9.11/11.sci
@@ -0,0 +1,18 @@
+clc;
+clear all;
+disp("heat transfer rate")
+L=0.5;//m
+b=1;//m
+ts=30;// degree C
+rho=980.3;//kg/m^3
+k=66.4*10^(-2);//W/m.C
+mu=434*10^(-6);// kg/ms
+hfg=2257*10^3;// J/kg
+g=9.81;// m/s
+tsat=100;// degree C
+ts=30;// degree C
+h=0.943*(rho^2*k^3*g*hfg/(mu*L*(tsat-ts)))^0.25;
+Q=h*L*b*(tsat-ts)*3600/1000;
+disp("kJ/h",Q,"rate of heat transfer per metre width, Q =")
+m=Q*1000/hfg;
+disp("kg/h",m,"The condensate rate per metre width =")
diff --git a/965/CH9/EX9.12/12.sci b/965/CH9/EX9.12/12.sci
new file mode 100644
index 000000000..c47264bcb
--- /dev/null
+++ b/965/CH9/EX9.12/12.sci
@@ -0,0 +1,20 @@
+clc;
+clear all;
+disp("film thickness at bottom")
+L=0.35;//m
+b=.42;//m
+ts=40;// degree C
+rho=977.8;//kg/m^3
+k=0.667;//W/m.C
+mu=400*10^(-6);// kg/ms
+hfg=2257*10^3;// J/kg
+g=9.81;// m/s
+tsat=100;// degree C
+del=(4*k*mu*(tsat-ts)*L/(g*rho^2*hfg))^0.25;
+disp("mm",del*1000,"The film thickness at the bottom of plate =")
+u=rho*g*del^2/(2*mu);
+disp("m/s",u,"Maximum velocity at the bottom of plate =")
+h=0.943*(rho^2*k^3*g*hfg/(mu*L*(tsat-ts)))^0.25;
+Q=h*L*b*(tsat-ts);
+disp("kW",Q/1000,"rate of heat transfer per metre width, Q =")
+
diff --git a/965/CH9/EX9.13/13.sci b/965/CH9/EX9.13/13.sci
new file mode 100644
index 000000000..21c28b680
--- /dev/null
+++ b/965/CH9/EX9.13/13.sci
@@ -0,0 +1,25 @@
+clc;
+clear all;
+disp("film thickness at bottom")
+L=0.6;//m
+b=1;//m
+ts=60;// degree C
+rhol=971.8;//kg/m^3
+k=67.413*10^(-2);//W/m.C
+mu=355.3*10^(-6);// kg/ms
+hfg=2257*10^3;// J/kg
+rhov=0.596;//kg/m^3
+g=9.81;// m/s
+tsat=100;// degree C
+del=(4*k*mu*(tsat-ts)*L/(g*rhol*(rhol-rhov)*hfg))^0.25;
+disp("mm",del*1000,"The film thickness at the bottom of plate =")
+h=4*k/(3*del);
+h=1.2*h;
+disp("W/m^2.C",h,"The overall heat transfer coefficient =")
+Q=h*L*b*(tsat-ts);
+disp("kW",Q/1000,"rate of heat transfer per metre width, Q =")
+m=Q/hfg;//kg/hr
+disp("kg/hr",m*3600,"Condensate flow rate =")
+Re=4*m/(mu*b);
+disp(Re,"Re =")
+
diff --git a/965/CH9/EX9.14/14.sci b/965/CH9/EX9.14/14.sci
new file mode 100644
index 000000000..487b4324e
--- /dev/null
+++ b/965/CH9/EX9.14/14.sci
@@ -0,0 +1,20 @@
+clc;
+clear all;
+disp("heat transfer rate")
+d=0.06;//m diameter
+L=1.2;//m
+ts=50;// degree C
+tsat=100;//degree C
+rhol=975;//kg/m^3
+mu=375*10^(-6);// Ns/m^2
+k=0.67;// W/m.C
+rhov=0.596;// kg/m^3
+hfg=2257*10^3;// J/kg
+g=9.81;//m/s
+h=1.13*(rhol*(rhol-rhov)*k^3*g*hfg/(mu*L*(tsat-ts)))^0.25;
+Q=h*(%pi*d*L)*(tsat-ts);
+disp("kW",Q/1000,"The rate of heat transfer =")
+m=Q/hfg;//kg/s
+disp("kg/h",m*3600,"rate of condensation of steam =")
+Re=4*m/(%pi*d*mu);
+disp(Re,"Re =")
diff --git a/965/CH9/EX9.15/15.sci b/965/CH9/EX9.15/15.sci
new file mode 100644
index 000000000..a91e32d7d
--- /dev/null
+++ b/965/CH9/EX9.15/15.sci
@@ -0,0 +1,18 @@
+clc;
+clear all;
+disp("rate of condensate formation")
+d=0.02;//m diameter
+ts=84;// degree C
+tsat=100;//degree C
+rhol=963.4;//kg/m^3
+mu=306*10^(-6);// Ns/m^2
+k=0.677;// W/m.C
+rhov=0.596;// kg/m^3
+hfg=2257*10^3;// J/kg
+g=9.81;//m/s
+h=0.725*(rhol*(rhol-rhov)*k^3*g*hfg/(mu*d*(tsat-ts)))^0.25;
+Ql=h*(%pi*d)*(tsat-ts);
+disp("W/m",Ql,"The rate of heat transfer =")
+ml=Ql/hfg;//kg/s
+disp("kg/h",ml*3600,"rate of condensation of steam =")
+
diff --git a/965/CH9/EX9.16/16.sci b/965/CH9/EX9.16/16.sci
new file mode 100644
index 000000000..c680f5f01
--- /dev/null
+++ b/965/CH9/EX9.16/16.sci
@@ -0,0 +1,19 @@
+clc;
+clear all;
+disp("heat transfer coefficient")
+n=625;// number of tubes
+N=n^0.5;
+d=0.006;//m diameter
+ts=25;// degree C
+tsat=54;//degree C
+rhol=992;//kg/m^3
+mu=663*10^(-6);// Ns/m^2
+k=0.631;// W/m.C
+rhov=0.098;// kg/m^3
+hfg=2373*10^3;// J/kg
+g=9.81;//m/s
+h=0.725*(rhol*(rhol-rhov)*k^3*g*hfg/(N*mu*d*(tsat-ts)))^0.25;
+disp("W/m^2.C",h,"The heat transfer coefficient =")
+ml=h*%pi*d*(tsat-ts)/hfg;//kg/s
+m=n*ml;
+disp("kg/s.m",m,"rate of condensation of steam for complete array =")
diff --git a/965/CH9/EX9.17/17.sci b/965/CH9/EX9.17/17.sci
new file mode 100644
index 000000000..c6112b5a0
--- /dev/null
+++ b/965/CH9/EX9.17/17.sci
@@ -0,0 +1,32 @@
+clc;
+clear all;
+disp("square plate")
+x=0.4;//m
+L=0.75;//mm
+ts=28;// degree C
+rhol=993.95;//kg/m^3
+k=62.53*10^(-2);//W/m.C
+mu=728.15*10^(-6);// kg/ms
+hfg=2402*10^3;// J/kg
+rhov=0.561;//kg/m^3
+g=9.81;// m/s
+tsat=42;// degree C
+delx=(4*k*mu*(tsat-ts)*x/(g*rhol*(rhol-rhov)*hfg))^0.25;
+disp("mm",delx*1000,"The film thickness at the bottom of plate =")
+hx=k/delx;
+disp("W/m^2.C",hx,"heat transfer coefficient =")
+delL=(4*k*mu*(tsat-ts)*L/(g*rhol*(rhol-rhov)*hfg))^0.25;
+disp("mm",delL*1000,"The film thickness at the bottom of plate =")
+hL=4*k/(3*delL);
+disp("W/m^2.C",hL,"heat transfer coefficient =")
+h=1.2*hL;
+disp("W/m^2.C",h,"The overall heat transfer coefficient =")
+Q=h*L*L*(tsat-ts);
+disp("kW",Q/1000,"rate of heat transfer per metre width, Q =")
+m=Q/hfg;//kg/hr
+disp("kg/hr",m*3600,"Condensate flow rate =")
+hinc=h*(sin(%pi*25/180))^0.25;
+disp("W/m^2.C",hinc,"heat transfer coefficient when the plate is inclined 25 degree with the horizontal")
+Re=4*m/(mu*L);
+disp(Re,"Re =")
+
diff --git a/965/CH9/EX9.18/18.sci b/965/CH9/EX9.18/18.sci
new file mode 100644
index 000000000..2a9409f45
--- /dev/null
+++ b/965/CH9/EX9.18/18.sci
@@ -0,0 +1,22 @@
+clc;
+clear all;
+disp("heat transfer rate")
+L=3.2;//m
+d=0.006;//m diameter
+ts=54;// degree C
+tsat=100;//degree C
+rhol=973.7;//kg/m^3
+mu=365*10^(-6);// Ns/m^2
+k=0.668;// W/m.C
+rhov=0.596;// kg/m^3
+hfg=2257*10^3;// J/kg
+g=9.81;//m/s
+disp("h=0.0077*(rhol*(rhol-rhov)*k^2*g/(mu^2))^0.333*Re^0.4")
+disp("Eliminating h from euqation we get the condition that the flow will be turbulent if ")
+disp("0.00296*((rhol*(rhol-rhov)*k^3*g*(tsat-ts)^3*L^3/(mu^5*hfg^3))^(5/9)>1800")
+x=0.00296*(rhol*(rhol-rhov)*k^3*g*(tsat-ts)^3*L^3/(mu^5*hfg^3))^(5/9);
+if(x>1800)
+Re=x
+h=0.0077*(rhol*(rhol-rhov)*k^2*g/(mu^2))^0.333*Re^0.4
+Q=h*L*1*(tsat-ts);
+disp("kW/m",Q/1000,"hear transfer rate per unit width =")
diff --git a/965/CH9/EX9.19/19.sci b/965/CH9/EX9.19/19.sci
new file mode 100644
index 000000000..4ac2a64b2
--- /dev/null
+++ b/965/CH9/EX9.19/19.sci
@@ -0,0 +1,20 @@
+clc;
+clear all;
+disp("heat transfer coefficient")
+m=1800/3600;// kg/s
+d=8/1000;//m
+ts=24;// degree C
+tsat=45.8;// degree C
+rhov=0.0676;// kg/m^3
+hf=2393*10^(3);// J/kg
+rhol=993.95;// kg/m^3
+k=62.53*10^(-2);// W/m.C
+mu=728.15*10^(-6);// kg/m.s
+n=400;
+N=n^0.5;
+h=0.725*(rhol*(rhol-rhov)*k^3*g*hfg/(N*mul*(tsat-ts)*d));
+disp("W/m^2.C",h,"Average heat transfer coefficient =")
+Q=m*hfg;
+L=Q/(%pi*d*h*(tsat-ts));
+disp("m",L,"Length of each tube, assuming single pass =")
+
diff --git a/965/CH9/EX9.2/2.sci b/965/CH9/EX9.2/2.sci
new file mode 100644
index 000000000..bd02d43dc
--- /dev/null
+++ b/965/CH9/EX9.2/2.sci
@@ -0,0 +1,13 @@
+clc;
+clear all;
+disp("the heat flux")
+d=1.25/1000;// m diameter of wire
+L=0.25;//m length of wire
+V=18;// V
+I=45;// amp
+Q=V*I;// W
+A=%pi*d*L;//m^2
+q=Q/A;// W/m^2
+disp("W/m^2",q,"the heat flux =")
+delTe=((1.58*q^0.75)/5.62)^(1/3);// degree C
+disp("degree C",delTe,"The excess temperature")
diff --git a/965/CH9/EX9.20/20.sci b/965/CH9/EX9.20/20.sci
new file mode 100644
index 000000000..ba6b28a7d
--- /dev/null
+++ b/965/CH9/EX9.20/20.sci
@@ -0,0 +1,28 @@
+clc;
+clear all;
+disp("cylindrical drum")
+d=0.35;// m diameter
+ts=80;// degree C
+rhol=956.4;//kg/m^3
+k=68.23*10^(-2);//W/m.C
+mu=283*10^(-6);// kg/ms
+hfg=2201.6*10^3;// J/kg
+vg=0.885;// m^3/kg
+rhov=1/vg;//kg/m^3
+g=9.81;// m/s
+m=70/3600;// kg/s
+tsat=120.2;// degree C
+disp("delL=(4*k*mu*(tsat-ts)*L/(g*rhol*(rhol-rhov)*hfg))^0.25")
+a=(4*k*mu*(tsat-ts)/(g*rhol*(rhol-rhov)*hfg))^0.25
+disp("delL=a*L^0.25")
+disp("hL=4*k/(3*delL)")
+b=1.2*4*k/(3*a)//hl=b*L^(-0.25)
+//Q=h*%pi*d*L*(tsat-ts)
+Q=m*hfg;
+L=(Q/(b*%pi*d*(tsat-ts)))^(4/3);
+disp("mm",L*1000,"length of drum =")
+delL=(4*k*mu*(tsat-ts)*L/(g*rhol*(rhol-rhov)*hfg))^0.25;
+disp("mm",delL,"Thickness of condensate layer =")
+Re=4*m/(mu*d);
+disp(Re,"Re =")
+
diff --git a/965/CH9/EX9.3/3.sci b/965/CH9/EX9.3/3.sci
new file mode 100644
index 000000000..2168fe212
--- /dev/null
+++ b/965/CH9/EX9.3/3.sci
@@ -0,0 +1,16 @@
+clc;
+clear all;
+disp("Volatge at burnout point")
+d=0.001;//m diameter of wire
+I=190;//amp
+L=0.4;//m length of wire
+rhol=958.4;//kg/m^3
+rhov=0.5955;//kg/m^3
+hfg=2257*10^3;//J/kg
+s=58.9*10^(-3);// N/m
+g=9.81;//m/s^2
+qsc=0.18*rhov^0.5*hfg*(g*s*(rhol-rhov))^0.25;// at burnout i.e. points of critical flux
+A=%pi*d*L;
+Q=A*qsc;
+Vb=Q/I;// V
+disp("V",Vb,"Voltage at burnout point =")
diff --git a/965/CH9/EX9.4/4.sci b/965/CH9/EX9.4/4.sci
new file mode 100644
index 000000000..95c81a377
--- /dev/null
+++ b/965/CH9/EX9.4/4.sci
@@ -0,0 +1,20 @@
+clc;
+clear all;
+disp("temperature at the bottom")
+m=25/3600;//kg/s
+d=0.28;// m diameter of copper pan
+tsat=100;// degree C
+rhol=958.4;// kg/m^3
+rhov=0.5955;// kg/m^3
+cpl=4220;//J/kg.K
+mul=279*10^(-6);//Pa.s
+Prl=1.75;
+hfg=2257*1000;// J/kg
+s=58.9*10^(-3);// N/m
+n=1;// for water
+A=%pi*d^2/4;// m^2
+qs=m*hfg/A;// W/m^2
+csl=0.013;
+te=(qs/(mul*hfg)*(s/(g*(rhol-rhov)))^0.5)^0.333*(csl*hfg*Prl/cpl);
+ts=tsat+te;
+disp("degree C",ts,"The temperature of the bottom surface of the plan")
diff --git a/965/CH9/EX9.5/5.sci b/965/CH9/EX9.5/5.sci
new file mode 100644
index 000000000..8f934ce98
--- /dev/null
+++ b/965/CH9/EX9.5/5.sci
@@ -0,0 +1,25 @@
+clc;
+clear all;
+disp("Power of burner")
+d=0.35;// diameter of pan
+ts=115;// degree C
+rhol=958.4;// kg/m^3
+rhov=0.5955;// kg/m^3
+cpl=4220;// J/kg.K
+mul=279*10^(-6);// Ns/m^2
+Prl=1.75;
+hfg=2257*10^3;// J/kg
+s=58.9*10^(-3);// N/m
+te=15;// degree C excess temperature
+g=9.81;//m/s^2
+n=1;
+csl=0.013;
+qs=mul*hfg*(g*(rhol-rhov)/s)^0.5*(cpl*te/(csl*hfg*Prl^n))^3// W/m^2
+Q=qs*%pi*d^2/4;//
+disp("W",Q,"Power of burner to maintain boiling =")
+mw=Q/hfg*3600;// kg/hr
+disp("kg/hr",mw,"Rate of evaporation =")
+qsc=0.18*(rhov)^0.5*hfg*(g*s*(rhol-rhov))^0.25;// W/m^2
+disp("W/m^2",qsc,"Critical heat flux =")
+
+
diff --git a/965/CH9/EX9.6/6.sci b/965/CH9/EX9.6/6.sci
new file mode 100644
index 000000000..bfd1f4b3d
--- /dev/null
+++ b/965/CH9/EX9.6/6.sci
@@ -0,0 +1,21 @@
+clc;
+clear all;
+disp("power dissipation/length")
+d=0.01;//m
+e=0.92;
+ts=260;// degree C
+rhol=958.4;// kg/m^3
+hfg=2257*10^3;//J/kg
+rhov=4.807;// k/m^3
+cpv=2.56*10^3;// J/kg.K
+k=0.0331;// W/m.K
+muv=14.85*10^(-6);// Ns/m^2
+mug=muv;;
+g=9.81;//m/s
+ta=100;// degree C
+te=ts-ta;// excess temperature
+hconv=0.65*(k^3*rhov*(rhol-rhov)*g*(hfg+0.4*cpv*te)/(muv*d*te))^0.25;
+hrad=5.67*10^(-8)*e*(ts^4-ta^4)/(ts-ta);
+h=hconv+3*hrad/4;
+Q=h*%pi*d*(ts-ta);//
+disp("W",Q,"power dissipation per unit length for the heater =")
diff --git a/965/CH9/EX9.7/7.sci b/965/CH9/EX9.7/7.sci
new file mode 100644
index 000000000..3a6fc3bc1
--- /dev/null
+++ b/965/CH9/EX9.7/7.sci
@@ -0,0 +1,15 @@
+clc;
+clear all;
+disp("different types of processes for condensation of capours on a solid surface")
+disp("there are two types of methods for condensation")
+disp("filmwise - in which condensation wets the surface forming a continuous film whic corners the entire surface")
+disp("dropwise - in which vapour condenses into small droplets of various sizes which fall down the surface in a random fashion")
+disp("filmwise - generally occurs on clean uncontaminated surfaces.")
+disp("in this type of condensation the film covering the entire surface grows in thickness as it moves down the surface by gravity.")
+disp("There exists a thermal gradient in the film and so it acts as a resistance to heat transfer")
+disp("Although a dropwise condensation would be preferred to filmwise condensation yet it is extremely difficult to achieve and maintain")
+disp("This is because most surface become wetted after being exposed to condensing vapours over a period of time. ")
+disp("Dropwise condensation can be obtained under controlled conditions with the help of certain additives to the condensate and various surface coatings,")
+disp("But its commercial viability has not yet been proved")
+disp("For this reason the condensaing equipments in use are designed on the basis of filmwise condensation.")
+
diff --git a/965/CH9/EX9.8/8.sci b/965/CH9/EX9.8/8.sci
new file mode 100644
index 000000000..ffc5e3204
--- /dev/null
+++ b/965/CH9/EX9.8/8.sci
@@ -0,0 +1,16 @@
+clc
+clear all;
+disp("local transfer coefficient")
+tsat=90;// degree C
+ta=70;// degree C
+L=1.5;//m
+d=2.5;//m outer diameter;//
+rhol=974;//kg/m^3
+k=0.668;// W/m.K
+mul=0.335*10^(-3);//kg/m.s
+hfg=2309*1000;//J/kg
+g=9.81;// m/s^2
+hL=((rhol^2)*(k^3)*g*hfg/(4*mul*L*(tsat-ta)))^0.25;
+disp("W/m^2.C",hL,"Local heat transfer coefficient =")
+h=4*hL/3;//
+disp("W/m^2.C",h,"average heat transfer coefficient =")
diff --git a/965/CH9/EX9.9/9.sci b/965/CH9/EX9.9/9.sci
new file mode 100644
index 000000000..bc3954ca6
--- /dev/null
+++ b/965/CH9/EX9.9/9.sci
@@ -0,0 +1,20 @@
+clc
+clear all;
+disp("average heat transfer coefficient")
+ts=120;// degree C
+d=2/100;//m
+L=0.2;//m
+ta=119;// degree C
+psat=1.985;// bar
+rhow=943;//kg/m^3
+hfg=2202.2*1000;//J/kg
+kw=0.686;// W/m.K
+mu=273.3*10^(-6);// Ns/m^2
+
+g=9.81;//m/s^2
+del=(4*kw*mu*(ts-ta)*L/(rhol^2*g*hfg))^0.25;//
+hL=k/del;
+disp("mm",del*1000,"Thickness of condensate film =")
+h=4*hL/3;
+disp("W/m^2.C",h,"Average heat transfer coefficient =")
+
generated by cgit (git 2.34.1) at 2025-03-07 20:26:54 +0000