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HeatPipe_CircArteries_Limits_CL

 

 

Call Heatpipe_CircArtery_Limits_CL(T_e, L_e, L_a, L_c, theta, R_in, Fluid$, th_ds, th_sc, R_artery, R_pore, A, N_artery, N_no, Flag: Q_dot_cap, Q_dot_sonic, Q_dot_entr)

The function HeatPipe_CircArtery_Limits_CL calculates the limits of performance of a circular artery heat pipe using the techniques described by Prenger (1979) and Woloshun and Merrigan (1988).  

 

Inputs:

 T_e - temperature of vapor leaving the evaporator [K, C, F, or R]

 L_e - length of evaporator [m or ft]

 L_a - length of adiabatic section [m or ft]

 L_c - length of condenser [m or ft]

 theta - angle of heat pipe [rad or deg], note that positive corresponds to evaporator down

 R_in - inner radius of heat pipe [m or ft]

 Fluid$ - fluid ('lithium', 'sodium', 'potassium', 'mercury', or 'water')

 th_ds - the thickness of the distribution screen [m or ft]

 R_artery - the radius of the arteries [m or ft]

 R_pore - effective pore radius for maintaining pressure difference at liquid-vapor interface [m or ft]

 A - velocity profile correction factor used by HTPIPE [-]

  A is defined as u^2/V^2 where u = local velocity and V = average velocity at the evaporator exit

  A = 1.234 for laminar flow and A = 2.22 for turbulent flow

 N_artery - number of operating arteries [-]

 N_no - number of non-operating arteries [-]

 Flag - flag to set flow condition, set to 0 to ignore

  1 = laminar vapor and laminar liquid

  2 = turbulent vapor and laminar liquid

  3 = laminar vapor and turbulent liquid

  4 = turbulent vapor and turbulent liquid

 

Outputs:

 Q_dot_cap - capillary limit [W or Btu/hr]

 Q_dot_sonic - sonic limit [W or Btu/hr]

 Q_dot_entr - entrainment limit [W or Btu/hr]

 

The units for the inputs to the function are based on the unit setting in EES. 

 

Example:

$Load Component Library

$UnitSystem SI Mass J K Pa Radian

$VarInfo Q_dot_sonic Units = 'W'

$VarInfo Q_dot_entr Units = 'W'

$VarInfo Q_dot_cap Units = 'W'

 

T_e = 775 [K]

L_e = 0.35 [m]

L_a = 0 [m]

L_c = 4.5 [m]

theta = 0 [rad]

R_in = 0.0185 [m]

Fluid$ = 'Potassium'

th_ds = 0.03048 [cm]*Convert(cm,m)

th_sc = 0.03048 [cm]*Convert(cm,m)

R_artery = 0.125 [cm]*Convert(cm,m)

R_pore = 0.0025 [cm]*Convert(cm,m)

N_artery = 3 [-]

N_no = 0 [-]

A = 1.234 [-]

Flag = 0 [-]

Call Heatpipe_CircArtery_Limits_CL(T_e, L_e, L_a, L_c, theta, R_in, Fluid$, th_ds, th_sc, R_artery, R_pore, A, N_artery, N_no, Flag: Q_dot_cap, Q_dot_sonic, Q_dot_entr)

 

 

{Solution:

Q_dot_cap = 24807 [W]

Q_dot_sonic = 20655 [W]

Q_dot_entr = 34928 [W]

}

 

Index