# Example 13.1     
 r0    =   0.890 g/cm^3
 T0   =   15.6 degC
 C0   =   0.00063 g/cm^3 degC
 T1  =   100.0 degC
 r = r0 - C0 * (T1 - T0)  ; g/cm^3 
 b0   =   0.220  cp cm^3 / s g
 d0   =   180.0 cp s cm^3 / g
 S1  =   58.0 s
 m1 = (b0 * S1 - d0 / S1) * r  ; cp ; reyn 

# Example 13.2     
 m1   =   0.050 Pa s
 n1  =   10.0 rps
 R1  =   50.0 mm
 c1  =   0.05 mm
 F1  =   5000.00 N
 L1  =   80.00 mm
 P1 = F1 / 2 / R1 / L1 ; Mpa 
 f1 = pi() * m1 * n1 * R1 / P1 / c1  
 T1 = f1 * F1 * R1  ; N m 
 Power = T1 * n1 ; W 

# Example 13.3     
 D1  =   2 in
 R  =   1 in
 c  =   0.0015 in
 n  =   50 rps
 W1  =   1000 lbf
 L1  =   1 in
 P = W1 / 2 / R/  L1 ; psi 
 mu   =   4.00E-06 reyn
 S = (R/c)^2 * (mu * n / 2 / pi() / P) 
 h0_over_c  =   0.30  # Fig 13.13
 h0 = h0_over_c * c ; in 
 x  =   5.40  # Fig 13.14
 f = x * (c / R)  
 P_over_pmax   =   0.32  # Fig 13.15
 pmax = P / P_over_pmax  ; psi 
 f  =   40.00 deg  # Fig 13.16
 qp0   =   54.00 deg  # Fig 13.17
 qpmax   =   16.90 deg  # Fig 13.17
 y  =   5.15  # Fig 13.18
 Q = y * R * c * n * L1 / (2 * PI()); in^3/s 
 Qs_over_Q   =   0.81  # Fig 13.19

# Example 13.4      
 P1  =   1.511 MPa 
 W1  =   17000 N 
 R  =   75 mm 
 L1 = W1 / 2 / R / P1 ; mm 
 L2 =  75 mm 
 L_over_D = L1 / 2 / R  
 mu   =   6.30 cp 
 n  =   30.0 rps 
 Slo   =   0.037 
 chi   =   0.138 mm 
 S1 = (R/chi)^2 * mu * n / P1  
 err1 = S1 - Slo   
 Shi   =   0.350 
 clo   =   0.0448 mm 
 S2 = (R/clo)^2 * mu * n / P1  
 err2 = S2 - Shi  
 f  =   0.0053  
 Tf = W1 * f * R  ; N m 
 Hf = Tf * n ; kW 
 Qs   =   2.15E-05 m^3/s 
 cr   =   1.36E+06 N/m^2 degC 
 Dt = Hf / Qs / cr  ; degCdiff

# Homework Problems:

TBD