Balanced Regenerator
A regenerator heat exchanger is an indirect heat transfer device where a hot fluid transfers heat to a solid at one point in the process and the solid then transfers heat to a cold fluid at a different point. A balanced regenerator is one where the hot and cold fluids have the same capacitance rate. The effectiveness-NTU solution is available for a balanced counterflow regenerator. A numerical model that can include unbalanced situations is available in the procedure RegeneratorHX. Solution is from Dragutinovic and Baclic.
Example:
$UnitSystem SI Mass J K Pa
$VarInfo UA C_dot Units = 'W/K'
$VarInfo C_matrix Units = 'J/K'
$VarInfo FlowTime Units = 's'
$VarInfo epsilon NTU Units = '-'
UA = 600 [W/K]
C_dot = 50 [W/K]
C_matrix = 500 [J/K]
FlowTime = 1 [s]
NTU = UA/C_dot
epsilon=hx('Regenerator', Ntu, C_dot, C_matrix/FlowTime, 'epsilon')
{Solution:
epsilon = 0.8559}