On the effect of structural forces on a condensing film profile near a fin-groove corner

Capillary boosting for enhanced heat pipe performance through bifurcation of grooves: Numerical assessment and experimental validation

“…The reason for these deviations may be attributed to the implementation of the 4 th -order polynomial approach for the modeling of condensing thin film. Fourth-order polynomial approach is a robust and widely accepted model; however, there is experimental evidence [44] that it may not accurately predict the film thickness on the fin top by enforcing slope continuity near the fin groove corner [45]. Accordingly, the transition of the liquid film on the fin top between the condenser and evaporator may not be properly captured.…”

“…Accordingly, the transition of the liquid film on the fin top between the condenser and evaporator may not be properly captured. Although comprehensive condensation models proposed for grooved heat pipes [45,46] are available in the literature, the implementation of these condensation models for the modeling of grooved heat pipes is not straightforward. The simulated and experimental results are tabulated in Table 2.…”

Fast and Predictive Heat Pipe Design and Analysis Toolbox: H-Pat

“…First and fore-most, it requires the analytical solutions and/or correlations for the liquid flow along the wick, which may not be available for unconventional complex geometries. Moreover, skipping the solution of detailed thin film phase change models may prevent obtaining the precise variation of the liquid film at a cross-section due to the absence of near wall effects such as dispersion and structural components of disjoining pressure (Akdag et al, 2020;Setchi et al, 2019). In addition, in its current form, H-PAT does not solve the vapor flow, thereby neglecting the associated viscous losses, and assumes uniform vapor properties along the heat pipe.…”

“…Counter flow of vapor and liquid results in viscous losses due to shear stresses between liquid-wall, vapor-wall and liquid-vapor at the interface. While the amount of mass transported through the adiabatic region remains nearly constant, the main change is along the evaporator and condenser regions; consequently, additional models (Akkus and Dursunkaya, 2016;Akdag et al, 2020) to account for phase change rates along the evaporator and condenser sections should be employed. When all of these effects are considered, the solution approach is to numerically solve the mass and momentum balance equations in both domains together with the Young-Laplace equation (Do et al, 2008;Lefèvre et al, 2008;Odabasi, 2014).…”