The Thermal—Flow Processes and Flow Pattern in a Pulsating Heat Pipe—Numerical Modelling and Experimental Validation

Abstract

The aim of the article is to numerically model a two-dimensional multiphase flow based on the volume of fluid method (VOF) in a pulsating heat pipe (PHP). The current state of knowledge regarding the modeling of these devices was studied and summarised. The proposed model is developed within open source software, OpenFOAM, based on the predefined solver called interPhaseChangeFoam. The analyses were carried out in terms of the influence of four different mass transfer models between the phases, proposed by Tanasawa, Lee, Kafeel and Turan, and Xu et al. on the shape and dynamics of the internal flow structures. The numerical models were validated against data obtained from a specially designed experimental setup, consisting of three bends of pulsating heat pipes. The numerical calculations were carried out with ethanol being treated as a working medium and the initial and boundary conditions taken directly from the measurement procedures. The variable input parameter for the model was the heat flux implemented in the evaporation section and a fixed temperature applied to the condensation section. The flow structures obtained from the numerical analyses were compared and discussed with the flow structures gained from experimental studies by employing a high speed camera. In addition, to verify the quantitative results obtained from the numerical analyses with the experimental data, a technique called particle image velocimetry (PIV) was used for the velocity vector field. For the analysed velocity ranges, the relative error obtained was reached at the level of 10%.

Thermal Investigations of Hemispherical Shell Vapor Chamber Heat Sink

“…Four sweep mesh models were analyzed to determine the appropriate mesh size for the CFD analysis. In particular, the current CFD simulation is a three-dimensional structure that is different from the two-dimensional modeling of previous research in the literature [45][46][47][48][49][50][51]. Moreover, Song et al [52] reported the importance of 3D simulation to reach accuracy and to see multidimensional flow behavior.…”

“…Several heat pipes [45][46][47][48][49][50][51][52] were subjected to numerical analysis. The volume of fluid (VOF) methodology, which is one of the most well-known methods, was used in their computational fluid dynamics to simulate the two-phase flow of liquid-vapor phases.…”

“…The computational fluid dynamics (CFD) modeling of heat pipes using a VOF model was used to address these issues by identifying the motion of all phases and indirectly characterizing the motion of the interfaces. Previous CFD simulation studies from the literature are two-dimensional simulation works [45][46][47][48][49][50][51]. This is induced by a long calculation time.…”

Turbulence and Fluid Mechanics

“…The article [7] titled "The Thermal-Flow Processes and Flow Pattern in a Pulsating Heat Pipe-Numerical Modelling and Experimental Validation" deals with very challenging and important problems related to multi-phase flows. Additionally, the authors present very interesting and original experiment of a flow in pulsating heat pipe.…”

1-D Modeling of Two Phase Flow Process in Concentric Annular Heat Pipe and Experimental Investigation

“…Blasiak et al [23] studied a pulsating heat pipe using 2-D multiphase simulation. For this simulation, the VOF (volume of fluid) model was adopted, and the analysis was carried out with various mass transfer models between phases.…”