LIBRARY
HeatTransfer.ConstantPhasic
Phase-resolved heat-transfer model with constant coefficients per regime.
For each cell, the heat-transfer coefficient is selected from the cell vapor quality: alpha_liq for liquid (x <= 0), alpha_vap for vapor (x >= 1), and alpha_2ph in the two-phase interior, with smooth transitions across the xdot_1 / xdot_2 boundaries. Drop this in wherever a PartialTwoPhaseHeatTransfer is required — e.g. the StraightPipe's heatTransfer slot.
This component extends from PartialTwoPhaseHeatTransfer
Usage
HVACComponents.HeatTransfer.ConstantPhasic(medium_data, surfaceAreas, lengths, dimensions, roughnesses, diameters=missing, As=missing, alpha0, ps_start, hs_start, alpha_liq, alpha_2ph, alpha_vap, xdot_1, xdot_2)
Parameters:
| Name | Description | Units | Default value |
|---|---|---|---|
N | Number of heat-transfer control volumes | – | |
medium_data | Refrigerant medium properties | – | |
surfaceAreas | Per-cell heat-transfer surface area [m^2] (length N) | – | |
lengths | Per-cell axial length [m] (length N) | – | |
dimensions | Per-cell characteristic dimension (hydraulic diameter) [m] (length N) | – | |
roughnesses | Per-cell wall roughness [m] (length N) | – | |
alpha0 | Nominal heat-transfer coefficient used as the solver guess for alphas [W/(m^2.K)] | – | |
ps_start | Initial pressure profile across the cells [Pa] (length N) | Pa | |
hs_start | Initial specific-enthalpy profile across the cells [J/kg] (length N) | J/kg | |
alpha_liq | Liquid-phase heat-transfer coefficient [W/(m^2.K)] | – | |
alpha_2ph | Two-phase heat-transfer coefficient [W/(m^2.K)] | – | |
alpha_vap | Vapor-phase heat-transfer coefficient [W/(m^2.K)] | – | |
xdot_1 | Lower vapor-quality blending bound between liquid and two-phase [-] (typically ~0.05) | – | |
xdot_2 | Upper vapor-quality blending bound between two-phase and vapor [-] (typically ~0.9) | – |
Connectors
heatPorts- This connector represents a thermal port with temperature and heat flow as the potential and flow variables, respectively. (HeatPort)
Variables
| Name | Description | Units |
|---|---|---|
vs | Per-cell mean velocity [m/s] (length N); typically bound externally | – |
Ts | Per-cell fluid temperature [K] (length N) | K |
ds | Per-cell fluid density [kg/m^3] (length N) | – |
m_flows | Per-cell mass flow rate [kg/s] (length N; = ds * vs * As) | kg/s |
alphas | Per-cell heat-transfer coefficient [W/(m^2.K)] (length N); extender supplies | – |
xs | Per-cell vapor quality [-] (length N); typically bound externally | – |
Q_flows | Per-cell heat flow into the fluid [W] (length N; = heatPorts[i].Q_flow) | W |