initial commit / add all books

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+clc

+p1 = 1 // Air pressure at compressure inlet in bar

+t1 = 30 // Air temperature at compressure inlet in degree Celsius

+p2 = 3.5 // Air pressure at compressure exit in bar

+t2 = 141 // Air temperature at compressure exit in degree Celsius

+v = 90 // Air velocity at compressure exit in m/s

+cp = 1.0035 // Specific heat capacity of air in kJ/kg

+y = 1.4 // Heat capacity ratio

+R = 0.287 // Gas constant

+printf("\n Example 8.20\n")

+T2s = (t1+273)*(p2/p1)^((y-1)/y)

+if T2s>(t2+273) then

+    printf("\n Part A:")

+    printf("\n There is heat loss to surrounding.")

+end

+n =(1/(1-((log((t2+273)/(t1+273)))/(log(p2/p1)))))

+printf("\n\n Part B:")

+printf("\n The polytropic index is %f ",n)

+Wa = cp*(t1-t2)-(v^2)/2000 // Actual work 

+Wt = -R*(t1+273)*log(p2/p1) - (v^2)/2000 // Isothermal work

+nt =Wt/Wa // Isothermal efficency

+printf("\n\n Part C:")

+printf("\n Isothermal efficiency is %f percent ",nt*100)

+df = cp*(t1-t2) + (t1+273)*(R*log(p2/p1) - cp*log((t2+273)/(t1+273))) -(v^2)/2000

+Wm = df // Minimum work input

+I = Wm-Wa // Irreversibility

+

+printf("\n\n Part D:")

+printf("\n The minimum work input is %f kJ/kg, and irreversibility is %f kJ/kg",Wm,I)

+// The answers given in the book contain round off error

+

+neta = Wm/Wa

+printf("\n\n Part E:")

+printf("\n Second law efficiency is %d percent",ceil(neta*100))

+