initial commit / add all books

10 files changed, 747 insertions, 0 deletions

diff --git a/3136/CH6/EX6.1/Ex6_1.sce b/3136/CH6/EX6.1/Ex6_1.sce
new file mode 100755
index 000000000..7a146d0fa
--- /dev/null
+++ b/3136/CH6/EX6.1/Ex6_1.sce
@@ -0,0 +1,70 @@
+clear all; clc;

+

+disp("Pick the data rows for the flow rates of 10241 and 13965 cfm and list them in the first four columns of the table below.")

+disp("Convert the flow rate Q,static pressure SP and brake horsepower BHP values for various rpm into 300rpm based on the fan laws.")

+disp("That is Q1=Q*(300/N), SP1=SP((300/N)^2),BHP1=BHP*((300/N)^3)")

+disp("Calculate the static efficiency using ETAs=(Q*SP)/(6346*BHP)")

+disp("The results are plotted into the chart")

+

+

+

+

+

+Q=[10241 10241 10241 10241 10241 10241 10241 13965 13965 13965 13965 13965 13965 13965 13965 ];

+SP= [0.25 0.375 0.5 0.625 0.75 1 1.25 0.25 0.375 0.5 0.625 0.75 1 1.25 1.5];

+N= [300 321 341 363 385 427 466 380 396 413 428 444 473 506 537];

+BHP= [0.82 1.03 1.23 1.45 1.68 2.19 2.75 1.58 1.86 2.16 2.43 2.72 3.3 3.89 4.51];

+

+Q1= zeros(1,length(Q));

+SP1 = zeros(1,length(Q));

+BHP1 = zeros(1,length(Q));

+ETA=zeros(1,length(Q));

+

+for i = 1: length(Q)

+   

+   Q1(i)=Q(i)*(300/N(i))

+   SP1(i)=SP(i)*((300/N(i))^2)

+   BHP1(i)=BHP(i)*((300/N(i))^3)

+   ETA(i)=(Q(i)*SP(i))/(6346*BHP(i))

+    

+end

+

+//disp("    phi     psi      eff(%)   pai        N(rpm)      Ps(mw)       Q(m^3/s)")

+

+table = [Q' SP' N' BHP' Q1' SP1' BHP1' ETA'];

+disp("     Q       SP        N        BHP        Q1          SP1          BHP1         ETA")

+disp("   (cfm)   (in.wg)    rpm                 (cfm)      (in.wg)")

+disp(table)

+

+plot(Q1,SP1,'o',Q1,BHP1,'d',Q1,ETA,'s')

+legend("SP1(in.wg)","BHP1(hp)","ETA",-1)

+xlabel("Q(cfm)")

+ylabel("SP1(in.wg), BHP1(hp) , ETA")

+set(gca(),"grid",[1 1])

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diff --git a/3136/CH6/EX6.10/Ex6_10.sce b/3136/CH6/EX6.10/Ex6_10.sce
new file mode 100755
index 000000000..be54d5c45
--- /dev/null
+++ b/3136/CH6/EX6.10/Ex6_10.sce
@@ -0,0 +1,71 @@
+clear all; clc;

+

+disp("From table 6.1 at 1.25 SP,the rotating speeds for Q1=11172cfm and Q2=12103cfm are N1=474rpm and N2=483 rpm respectively")

+Ns=474+[(483-474)*(12000-11172)]/[12103-11172]

+printf(" Hence the rotating speed for the selected fan is determined by inetrpolation %0.0f rpm\n\n",Ns)

+

+disp("Select a few data points around 482 rpm from table 6.1 as:")

+Q=[14896 12103 11172  11172 10241 7448];

+N=[490 448 436 474 466 360];

+SP=[1.0 1.0 1.0 1.25 1.25 0.75];

+BHP=[3.66 2.67 2.40 2.97 2.75 1.2];

+

+disp(" Q(cfm)   N(rpm)   SP(in.wg)   BHP(hp)")

+table=[Q' N' SP' BHP']

+disp(table)

+

+disp("Convert them into conditiond of 482 rpm according to the similarity laws,resulting in")

+Q1=[14653 13021 12350 11360 10593 9972];

+SP1=[0.967 1.16 1.22 1.29 1.34 1.34];

+BHP1=[3.5 3.20 3.24 3.12 3.04 2.88];

+table1=[Q1' SP1' BHP1']

+disp(" Q(cfm)   SP(in.wg)   BHP(hp)")

+disp(table1)

+

+disp("The system curve can be calculated from the following table")

+

+Q2=[10000 11000 12000 13000 14000];

+H2=[0.87 1.05 1.25 1.47 1.70];

+

+sqrQ2 = zeros(1,length(Q2));

+

+for i = 1: length(Q2)

+   

+

+   sqrQ2(i) = [Q2(i)]^2;

+    

+end

+

+

+table2=[Q2' H2']

+disp("  Q(cfm)  H(in.wg)")

+disp(table2)

+

+disp("The system curve can be calculated from H versus Q^2. It is plotted as shown.")

+//The system curve has not been provided in the book for this numerical. However they have mentioned that the parameters for the curve are H and Q^2,and as such has been plotted here.

+plot(sqrQ2,H2)

+xlabel("Q^2 ")

+ylabel("H")

+set(gca(),"grid",[1 1])

+xtitle("System curve: H versus Q squared")

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diff --git a/3136/CH6/EX6.2/Ex6_2.sce b/3136/CH6/EX6.2/Ex6_2.sce
new file mode 100755
index 000000000..a073072e3
--- /dev/null
+++ b/3136/CH6/EX6.2/Ex6_2.sce
@@ -0,0 +1,53 @@
+clear all; clc;

+

+disp("Assume as given Na=2400 rpm")

+disp("T1a=68 degrees Farenheit=528R,p1=14.7 psia,p2a=8.5psig=23.2 psia")

+disp("Qa=1800cfm,Eta=0.70 Nb=3600rpm and T1b=50 to 95 degrees Farenheit")

+

+Q_a=1800

+N_b=3600

+N_a=2400

+Q_b=Q_a*(N_b/N_a)

+printf("\n Qb= %0.0f cfm",Q_b)

+

+disp("((p2/p1)_b)^((k-1)/k)-1=(T1a/T1b)*[((p2/p1)_a)-1]*((Nb/Na)^2)")

+disp("On simplifying ((p2/p1)_b)=0.313*(T1a/T1b)")

+disp("We obtain p2b=14.7*[1+0.313*(T1a/T1b)]^3.5=36.6 to 39.3 psia")

+disp("Also Psb=rho_1b*Q_b*H_i/Eta={(p_1b/(R*T_1b))*Qb*Cp*T_1b*[(p2/p1)^((k-1)/k)-1]}/Eta")

+disp("Psb=[(3.5*14.7*144*2700/(550*60))*0.313*(T1a/T1b)]/0.7")

+disp("Psb=271*(T1a/T1b)=257.8 to 280.6hp")

+

+disp("From rho_0*Q_dash=rho_1*Q,we have the flow rate measured at the standard condition,Q_dashb=(rho_1b/rho_0)*Qb=(T0/T1b)*Qb=2795 to 2568 cfm")

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diff --git a/3136/CH6/EX6.3/Ex6_3.sce b/3136/CH6/EX6.3/Ex6_3.sce
new file mode 100755
index 000000000..022d923de
--- /dev/null
+++ b/3136/CH6/EX6.3/Ex6_3.sce
@@ -0,0 +1,84 @@
+clear all; clc;

+//Answer of H_ib given in the book is 5830,however it is incorrect. The correct answer is found out to be 5837.4883

+

+disp("rho_a=p/(R*T)")

+rho_a=(13.7*0.491*144)/(53.33*(-10+460))

+printf(" rho_a= %0.5f lbm/ft^3",rho_a)

+

+disp("Qb=Q*(Nb/Na)")

+Q=(180/0.0403)*(12000/25000)

+printf(" q= %0.0f cfm",Q)

+

+disp("Hb=Ha*((Nb/Na)^2)")

+disp("we obtain")

+disp("((p2/p1)^((k-1)/k)_b)=[((p2/p1)^((k-1)/k)_a)-1]*((Nb/Na)^2)*(T1a/T1b)+1")

+//let x=((p2/p1)^((k-1)/k)_b)

+p2=34.5

+p1=13.7

+//let y=((k-1)/k)

+y=0.2857

+Nb=12000

+Na=25000

+T_1a=450

+T_1b=535

+x=[(p2/p1)^(y)-1]*((Nb/Na)^2)*(T_1a/T_1b)+1

+printf(" ((p2/p1)^((k-1)/k)_b)=%0.4f\n",x)

+

+disp("So p2b=((1.0585)^3.5)*(p1b)")

+p_1b=30

+p_2b=((1.0585)^3.5)*(p_1b)

+printf(" p2b= %0.1f in.Hg",p_2b)

+

+disp("H_ib=[(k*R*T_1b)/(k-1)]*[((p2/p1)^((k-1)/k)_b)-1]")

+k=1.4

+R=53.33

+T_1b=535

+p2=36.6

+p1=30

+y=0.2857

+H_ib=[(k*R*T_1b)/(k-1)]*[((p2/p1)^y)-1]

+printf(" H_ib=%0.4f ft-lbf/lbm",H_ib)//Answer of H_ib given in the book is 5830,however it is incorrect. The correct answer is found out to be 5837.4883 on calculating

+

+disp("rho_b*Qb=mb")

+mb=(30*0.491*144)/(53.33*535)*2144

+printf(" mb= %0.1f lbm/min",mb)

+

+disp("Thus Psb=mb*Hib/Eta")

+P_sb=159.4*5830/(60*550*0.70)

+printf(" Psb= %0.1f hp",P_sb)

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diff --git a/3136/CH6/EX6.4/Ex6_4.sce b/3136/CH6/EX6.4/Ex6_4.sce
new file mode 100755
index 000000000..6adac7dc4
--- /dev/null
+++ b/3136/CH6/EX6.4/Ex6_4.sce
@@ -0,0 +1,21 @@
+clear all; clc;

+

+Q_c=1000

+N_a=3550

+N_c=4000

+Q_a=Q_c*(N_a/N_c)

+printf("\n Qa=Qc*(Na/Nc)=%0.1f cfm",Q_a)

+

+disp("H=Cp*T1*[(p2/p1)^((k-1)/k)-1]")

+disp("Ha/Hc=((Na/Nc)^2)")

+disp("Where ka=1.40,Cpa=0.24 Btu/lbm*degrees Farenheit,,T1a=530R,((ka-1)/ka)=0.2857 and kc=1.30")

+disp("Cpc=0.20Btu/(lbm*degrees Farenheit),T1c=550R,((kc-1)/kc)=0.2307, we have:")

+disp("(Cpa*T1a)*[[(p2/p1)^((k-1)/k)-1]]_a/{(Cpc*T1c)*[[(p2/p1)^((k-1)/k)-1]]_c}=((3550/4000)^2)")

+//let x=(Cpa*T1a)*[[(p2/p1)^((k-1)/k)-1]]_a/{(Cpc*T1c)*[[(p2/p1)^((k-1)/k)-1]]_c}

+x=((3550/4000)^2)

+printf(" Thus the value is equal to %0.3f",x)

+

+disp("Or")

+disp("(0.24*530*[(p2/p1)^(0.2857-1]_a)/(0.20*550*[(19.7/17.7)^(0.2307)-1])=0.787")

+disp("Hence ((p2/p1)^0.2857)_a=1+(0.787*0.025)/1.156=1.017")

+disp("p2a=15.6 psia")

diff --git a/3136/CH6/EX6.5/Ex6_5.sce b/3136/CH6/EX6.5/Ex6_5.sce
new file mode 100755
index 000000000..3e8c17b5d
--- /dev/null
+++ b/3136/CH6/EX6.5/Ex6_5.sce
@@ -0,0 +1,17 @@
+clear all; clc;

+//the answer of p02b given in the book is 94.1,however the right answer is 92.05 which is rounded off to 92.1 here

+

+p_02b=90+0.5*0.00237*((500)^2)/144

+printf("\n p02b= %0.1f psia",p_02b)

+

+//let x=T02/T01

+x=(480+460)/(60+460)

+printf("\n T02/T01= %0.4f which is also =(94.1/14.7)^((0.2857)/(Eta_p)) ",x)//answer given in the book is 94.1,which is substituted

+disp("From (0.2857/Eta_p)*ln(94.1/14.7)=ln(1.807) we can obtain the polytropic efficiency")

+Eta_p=(log(94.1/14.7)/log(1.807))*0.2857

+printf("Eta_p= %0.4f",Eta_p)

+

+disp("0.85=[(4.5)^(0.2857)-1]/[(4.5)^(0.2857/Eta_p)-1")

+disp("Thus 0.5638/((4.5^(0.2857/Eta_p))-1)")

+disp("We have polytropic efficiency for compressor A,Eta_pa=0.878.")

+disp("Hence,compressor bB is moe efficient")

diff --git a/3136/CH6/EX6.6/Ex6_6.sce b/3136/CH6/EX6.6/Ex6_6.sce
new file mode 100755
index 000000000..7810a61f7
--- /dev/null
+++ b/3136/CH6/EX6.6/Ex6_6.sce
@@ -0,0 +1,80 @@
+clear all; clc;

+

+disp("The specifications are N=1800 rpm=188.5 rad/s,Q=14000cfm=233.3 cfs,and sp=5 in.wg")

+N=1800 

+Q=233.3

+sp=5 

+Ns=N*(Q^0.5)/(sp^0.75)

+disp("Ns=%0.0f rpm*(cfm^0.5)/(in water^0.75)")

+

+disp("From Figure 5.1,selecting the air foil blade,we have Etas=0.80 and Ds=d2*(sp^0.25)/Q^0.5=0.33")

+

+Q=14000

+sp=5

+Eta_s=0.8

+P_s=Q*sp/(Eta_s*6356)

+printf(" Ps=%0.2f hp",P_s)//incorrectly rounded off in the book

+

+d2=0.33*(14000^0.5)/(5^0.25)

+printf("\n d2=%0.0f in",d2)

+

+tau=(13.7*550)/(1800*%pi/30)

+printf("\n τ=%0.0f lbf-ft",tau)

+

+tau=40

+s_s=10000

+ds=[(16*tau)/(%pi*s_s)]^(1/3)

+printf("\n The shaft diameter is found out to be %0.2f in",ds)

+disp("Where s_s is the assumed maximum allowable shear stress of the shaft material.")

+disp("Hence d_d is set as 0.75in and d_h=1.0in or rh=0.5in. Using the maximum W1 criteria,we ave ßf1=35.2 degrees and r1=9.88 inches which is rounded off to 10 inches.")

+

+disp("Also we have b1=5 inches and ßb1=ßf1+i=37 degrees")

+omega=188.5

+r2=13/12

+U2=omega*r2

+printf(" To determine outlet dimensions we have U2= %0.1f ft/s",U2)

+

+disp("For a straight blade we have ßdashb2=52 degrees, so try ßb2=45 degrees")

+disp("Zb=26 and mu_s=0.794")

+disp("Since the static pressure is specified but the total pressure is needed in the Euler equation,the discharge flow is needed.")

+disp("Setting b2=b1=5 incheswe can determine the values of A2 and A3")

+

+r2=13

+b2=5

+A2=2*%pi*r2*b2/144

+printf(" A2=%0.3f ft^2",A2)

+

+A2=2.83

+A3=1.5*A2

+printf("\n The fan discharge area A3 is set as A3=1.5*A2=%0.2f ft^2",A3)

+disp("Hence we have V3=Q/A3=54.8 ft/s")

+

+sp=62.4*5/12

+rho=0.00237

+V3=54.8

+tp=sp+(0.5)*rho*(V3^2)

+printf(" tp=%0.2f lbf/ft^2",tp)

+

+disp("Also Eta_t=Eta_s*(tp/sp)=Eta_imp*Eta_v*Eta_m and assuming Eta_v*Eta_m=0.95")

+Eta_imp=((0.8*29.5)/26)/(0.95)

+printf(" So we hae Eta_imp= %0.4f",Eta_imp)

+

+disp("So from the Euler equation, we have (29.5/0.00237)=154.8*(204.2-(82.4/tanßb2))")

+disp("ß_b2=33.6 degrees")

+disp("Since Zb and mu_s are related to ßb2,we have to repeat the calculations")

+disp("The new alues Zb=20 and mu_s=0.781 and ß_b2=33.9 degrees are obtained")

+disp("Hence the final values are 20 and ß_b2=33.9 degrees")

+

+disp("From equation(6.12) we have(dΘ/dr)=(1/(2*tanßf1)*[2*(r/r1)*(1/r1)]")

+disp("Hence tanßdash_b2=[dr/(r*dΘ)_r2]=tanßf1*((r1/r2)^2)")

+tan_beta_dashb2=tan((35.2*%pi/180)*[(10/13)^2])

+printf(" Thus the value of tanßdash_b2= %0.3f",tan_beta_dashb2)//Answer f=given in the book is 0.417,however the more correct answer is 0.380

+betab2dash=((atan(tan_beta_dashb2))*180/%pi)

+printf("\n ß_dash_b2= %0.1f degrees",betab2dash)//Since value of tanß'b2 is different,ß'b2 is different

+disp("This value is smaller than ßb2 which is expected from 6.13c")

+

+

+

+

+

+

diff --git a/3136/CH6/EX6.7/Ex6_7.sce b/3136/CH6/EX6.7/Ex6_7.sce
new file mode 100755
index 000000000..fbb6862be
--- /dev/null
+++ b/3136/CH6/EX6.7/Ex6_7.sce
@@ -0,0 +1,193 @@
+clear all; clc;

+

+disp("Inlet Configuration selection: Mr1,t=0.75 and ßf1=25 degrees")

+M_r1t=0.75

+beta_f1=25*%pi/180

+M_1t=M_r1t*sin(beta_f1)

+printf(" M_1t=%0.3f",M_1t)

+

+disp("T1=To1/(1=((k-1))*(M_lt^2)/2")

+T1=530/(1+0.2*(0.317^2))

+printf("\n Thus the value of T1= %0.1fR",T1)

+

+a1=(1.4*53.33*32.2*519.6)^0.5

+printf("\n a1= %0.2f ft/s",a1)//answer provided here is more accurate 

+

+V_1t=0.317*1117.6

+printf("\n V1=%0.1f ft/s",V_1t)

+

+W_1t=0.75*1117.6

+printf("\n W_1t= %0.1f ft/s",W_1t)

+

+U_1t=[(838.2^2)-(354.3^2)]^0.5

+printf("\n U_1t= %0.1f ft/s",U_1t)

+

+omega=1623

+U_1t=759.6

+r_1t=U_1t/omega

+printf("\n So we have r_1t= %0.3f ft=5.6in",r_1t)

+

+//let x=k/k-1

+x=3.5

+po1=14.7

+T_1=519.6

+T_o1=530

+p1=po1*[(T_1/T_o1)^x]

+printf("\n So we have p1= %0.1f psia",p1)

+

+p1=13.7

+R=53.33

+T1=519.6

+rho1=(p1*144)/(R*T_1)

+printf("\n rho1= %0.4f lbm/ft^3",rho1)

+

+m=17

+rho1=0.0713

+V1=354.3

+A1=m/(rho1*V1)

+printf("\n A1= %0.3f ft^2=96.9 in ^2,assuming uniform inlet flow.\n\n",A1)

+

+disp("From pi*[(r_1t^2)-(r_1h^2)]=A1")

+disp("We have r_1h={[(r_1t^2)-A1]/pi}^0.5=0.72 in")

+disp("U_1h=97.0 ft/s")

+

+disp("ß_f1,h=taninverse(V_1h/U_1h)")

+V_1h=354.3

+U_1h=97

+beta_f1h=(atan(V_1h/U_1h))*180/%pi

+printf(" ßf1= %0.1f degrees",beta_f1h)

+

+disp("(B) Outlet Configuration From")

+

+Cp=0.24

+To1=530

+//let y=(k-1)/k=0.2857

+y=0.2857

+//let m=po2/po1

+m=2.5

+H_ad=Cp*To1*778*[(m)^(y)-1]

+printf(" H_ad=H_ad=Cp*To1*778[(po2/po1)^((k-1)/k)-1] %0.0f ft-lbf/lbm ",H_ad)

+

+m=17

+rho1=0.0713

+Q1=m/rho1

+printf("\n Q1=%0.1f ft^3/s",Q1)

+

+N=15500

+H_ad=29614

+Q1=238.4

+Ns=N*(Q1^0.5)/((H_ad)^0.75)

+printf("\n We obtain specific speed %0.0f rpm*{(ft^3/s)^0.5}(ft-lbf/lbm)^0.75 ",Ns)

+

+disp("Fom figure 6.7 we have estimated Eta_c=0.87 and Ds=D2*(H_ad)/(Q1^0.5)=1.50")

+D2=1.5*(238.4^0.5)/(29614^0.25)

+printf("\n D2=%0.4f ft=21.2 inches or r2=10.6 in. and U2=r2*omega=1433.7 ft/s",D2)

+

+disp("Referring to figure 6.16c,we have T_sso3=T_o1*(po3/po1)^((k-1)/k)")

+//((k-1)/k)=x

+x=0.2857

+T_o1=530

+//let l=po3/po1

+l=2.5

+T_sso3=T_o1*(l^x)

+printf(" T_sso3= %0.1f R ",T_sso3)

+disp("From Eta_c=(T_sso3-(T_o1))/(To3-To1) we have To2=To3")

+//let l=To2/To3

+l=(1/0.87)*(688.6-530)+530

+printf(" To2/To3 %0.1fR",l)

+disp("Also from Etam=U2*Vu2/[Cp*(T_o2-T_o1)]")

+

+Vu2=0.95*0.24*778*32.2*(712.3-530)/(1433.7)

+printf(" With the estimated Eta_m=0.95,Vu2=%0.1f ft/s",Vu2)

+

+disp("Flow coefficient φ=Vm2/U2=0.30 ")

+Vm2=0.3*1433.7

+printf(" Vm2=%0.1f ft/s",Vm2)

+

+disp("W2=[Vm2^2+(U2-Vu2)^2]^0.5=827.9 ft/s")

+disp("V2=[Vu2^2+Vm2^2]^0.5=844.1 ft/s")

+

+W1t=838.2

+W2=827.9

+Df=W1t/W2

+printf(" Hence we have diffusion factor Df=%0.3f. The value is less than 1.9 which is okay.",Df)

+

+disp("The impeller efiiciency can be estiamted form the losses fraction X=(1-Eta_imp)/(1-Eta_c) is approximately =0.6 ")

+Eta_imp=1-0.6*(1-0.87)

+printf("\n Eta_imp %0.3f",Eta_imp)

+

+disp("Hence from Eta_imp=(T_so2-T_o1)/(T_o2-T_o1),we have T_so2=T_o1+Eta_imp*(To2-T_o1)=698R and po2=po1*(T_so2/T_o1)^(k/(k-1))")

+po1=14.7

+T_so2=698.1

+T_o1=530

+//Let x=(k/(k-1))

+x=3.5

+po2=po1*(T_so2/T_o1)^x

+printf(" po2=%0.2f psia ",po2)

+

+disp("Then from the energy equation we have T2=T_o2-V2^2/(2*Cp)=653.0R")

+disp("Hence p2=p02*(T2/To2)^(k/(k-1))=28.4psia and rho2=p2/(R*T2)=0.117lbm/ft^3")

+

+disp("Selecting Zb=16 and using the Stanitz fromula for the slip coefficient we have Vdash_u2=Vu2+0.63*pi*U2/Zb")

+Vu2=726.3

+U2=1433.7

+Zb=16

+ Vdash_u2=Vu2+0.63*%pi*U2/Zb

+printf(" Vdash_u2= %0.1f ft/s",Vdash_u2)

+

+disp("tanß_b2=Vm2/(U2-Vdash_u2)")

+Vm2=430.1

+U2=1433.7

+Vdash_u2=903.6

+tan_beta_b2=Vm2/(U2-Vdash_u2)

+printf(" tanß_b2=%0.2f ",tan_beta_b2)

+

+betab2=(atan(tan_beta_b2))*180/%pi

+printf("\n ß_b2= %0.0f degrees",betab2)

+

+disp("With blade thickness t=0.15,contraction factor is determined")

+Zb=16

+t=0.15

+betab2=39*%pi/180

+D2=21.3

+epsilon2=1-[(Zb*t)/(sin(betab2))]/(%pi*D2)

+printf(" Thus epsilon2= %0.2f",epsilon2)

+

+disp("Hence from the mass equation we can determine b2")

+b2=17/(0.117*430.1*%pi*1.765*0.94)

+printf(" b2=%0.4f=0.7 8inch",b2)

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

diff --git a/3136/CH6/EX6.8/Ex6_8.sce b/3136/CH6/EX6.8/Ex6_8.sce
new file mode 100755
index 000000000..3258ac015
--- /dev/null
+++ b/3136/CH6/EX6.8/Ex6_8.sce
@@ -0,0 +1,65 @@
+clear all; clc;

+

+disp("Using figure 6.7 the specific speed Ns=N(V1^0.5)/(H_ad^0.75) should be calculated based on the inlet volumetric  flow rate V1 and the adiabetic head per stage H_ad")

+p1=14.7

+R=53.3

+T1=530

+rho1=p1*144/(R*T1)//144 is conversion factor.the actual formula is rho1=p1/(R*T1)

+printf(" From rho1=p1/(R*T1) =%0.3f lbm/ft^3, we have V1",rho1)

+

+V1=100/0.075

+printf("\n Thus V1= %0.0f ft^3/s.",V1)

+

+disp("Also from equation (A.3), we have total adiabetic head ΣH_ad=Cp*T1*[(pe/pi)^((k-1)/k)-1]")

+Cp=0.24

+T1=530

+pe=50

+pi=14.7

+//Let y= (k-1)/k

+y=0.2857

+H_ad=Cp*T1*778*[{(pe/pi)^(y)}-1]//778 is conversion factor

+printf(" Thus ΣH_ad= %0.0f lbf-ft/lbm \n",H_ad)

+

+disp("The specific speeds for different number of stages are calculated as follows ")

+

+Ns=4800*(1333^0.5)/(41436^0.75)

+printf(" For n=1 , Ns=4800*(1333^0.5)/(41436^0.75)=%0.0f ",Ns)

+

+Ns=4800*(1333^0.5)/(13812^0.75)

+printf("\n For n=3 , Ns=4800*(1333^0.5)/(13812^0.75)=%0.2f ",Ns)

+

+Ns=4800*(1333^0.5)/(10359^0.75)

+printf("\n For n=4 , Ns=4800*(1333^0.5)/(10359^0.75)=%0.0f ",Ns)

+

+Ns=4800*(1333^0.5)/(6906^0.75)

+printf("\n For n=6 , Ns=4800*(1333^0.5)/(6906^0.75)=%0.0f ",Ns)

+

+Ns=4800*(1333^0.5)/(5179^0.75)

+printf("\n For n=8 , Ns=4800*(1333^0.5)/(5179^0.75)=%0.0f ",Ns)

+

+disp("Reading the curves in figure 6.7,the best efficient point is around Ns=280 with Eta=0.90")

+disp("ds=D*(H_ad^0.25)/(V1^0.5)=0.7")

+disp("Hence 8 stage mixed flow impellers are selected.")

+

+D=0.7*(1333^0.5)/((41436/8)^0.25)

+printf(" The impeller diameter is calculated to be = %0.1f ft",D)

+

+m=100

+H_ad=41436

+Eta=0.9

+Ps=m*H_ad/(Eta*550)//converting units

+printf("\n The total required shaft power Ps=m*H_ad/(Eta)=%0.0f hp",Ps)

+

+

+

+

+

+

+

+

+

+

+

+

+

+

diff --git a/3136/CH6/EX6.9/Ex6_9.sce b/3136/CH6/EX6.9/Ex6_9.sce
new file mode 100755
index 000000000..7e8d593bd
--- /dev/null
+++ b/3136/CH6/EX6.9/Ex6_9.sce
@@ -0,0 +1,93 @@
+clear all; clc;

+

+disp("The inlet specific volume is calculated from the ideal gas equation")

+R=53.3

+T1=580

+p1=65

+nu1=(R*T1)/(144*p1)

+printf(" nu1=%0.3f ft^3/lbm=",nu1)

+

+disp("Q1=m*v1=4594 cfm")

+

+R=53.3

+T1=580

+//let y=(n/(n-1))

+y=2.625

+p2=250

+p1=65

+H_oa=R*T1*(y)*[(p2/p1)^(1/y)-1]

+printf(" The overall adiabetic head is calculated as H_o/a= %0.0f ft-lbf/lbm",H_oa)

+

+y=(0.75*1.4)/(1.4-1)

+printf("\n Where n/(n-1)=(Eta_p*k)/(k-1)=%0.3f",y)

+

+disp("From figure 6.7 , a centrifugal compressor with speed N=10000rpm is appropriate for the present application")

+

+disp("To use figure 6.7,the specific speed can be calculated from Ns=N*(V1^0.5)/(H_ad^0.75)")

+V1=4954/60

+printf(" Where V1= %0.1f cfs",V1)

+disp("H_ad=(H_o/a)/Eta_s is the head for each stage .")

+disp("Selecting the number of stages to be 2,4, and 6,the head for each stage and specific speed  can be calculated,then the total-to=total adiabetic efficiencies can be read ")

+disp("The required shaft horse power can be calculated with the volumetric and mechanical efficiencies assumed to be 0.98 and 0.95 respectively")

+disp("That is Ps=(m*(H_o/a)/(33000*Eta_ad*Eta_v*Eta_m)")

+

+H_oa=54417

+V1=82.6

+Eta_v=0.98

+Eta_m=0.95

+N=10000

+

+StageNo=[2 4 6];

+Eta_ad=[0.72 0.83 0.87];

+

+

+H_ad= zeros(1,length(StageNo));

+Ns = zeros(1,length(StageNo));

+Ps = zeros(1,length(StageNo));

+

+for i = 1: length(StageNo)

+   

+

+    H_ad(i) =H_oa/(StageNo(i));

+    Ns(i) =N*(V1^0.5)/(H_ad(i)^0.75);

+    Ps(i) = (m*H_oa)/(33000*Eta_ad(i)*Eta_v*Eta_m);

+end

+

+disp("StageNo   H_ad          Ns       Eta_ad      Ps")

+disp("       (ft-lbf/lbm)                         (hp)")

+table = [StageNo' H_ad' Ns' Eta_ad' Ps'];

+disp(table)

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

+

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