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In order to develop the liquid cooling plate of the battery pack with high efficiency, low resistance and uniform temperature, a special-shaped pin fin was proposed, and the influence mechanism of its structure and arrangement parameters on the flow and heat transfer performance in the flow channel of the liquid cooling plate is investigated numerically, and the temperature uniformity coefficient was used to quantify the distribution of temperature to verify the comprehensive heat dissipation performance. The results show that the arrangement of the pin fin disturbs the flow in the channel and increases the flow velocity near the upper surface of the channel, which is beneficial to enhance heat dissipation and increases the flow resistance at the same time; When the parameters of structure and layout of the pin fin are in a certain range, the comprehensive performance coefficient TP of the flow in the channel is greater than 1, in other words, the combined performance of the flow in the channel is improved. When the height ratio is 0.7, the width-length ratio is 0.5, the width ratio is 0.3, and the spacing ratio is 1.0, the TP of flow heat transfer in the flow channel is the best, and when Re = 1000, the TP of flow heat transfer is improved by 58%; When this pin fin is applied to the serpentine channel of the cooling plate of an in-use engineering vehicle, the highest temperature of the cooling plate is reduced by 3.5 K, the temperature difference is reduced by 3.5 K. The temperature uniformity coefficient is reduced by 56%, that is the heat dissipation performance of the liquid cooling plate can be improved comprehensively after adding the pin fin. [ABSTRACT FROM AUTHOR]

In this article, analysis of average Nusselt number (Nu avg), which indicates the heat removal from the battery pack cooled by flowing fluid is carried out considering coupled heat transfer condition at the pack and coolant interface. Five categories of coolant, mainly gases, common oils, thermal oils, nanofluids, and liquid metals, are selected. In each coolant category, five fluids (having different Prandtl number Pr) are selected and passed over the Li-ion battery pack. The analysis is made for different conductivity ratio (Cr), heat generation term (Q gen), Reynolds number (Re), and Pr. Pr varying in the range 0.0208–511.5 (25 coolants) and Cr for each category of coolant having its own upper and lower limit are used to analyze the heat removed from the battery pack. Using single feed-forward network and integrating two feed-forward networks having multi-layers with back-propagation is employed for artificial neural network (ANN) modelling. In this modelling, the concept of the main network and space network is devised for multiple back propagation (MBP). The numerical analysis revealed that the temperature distribution in battery and fluid is greatly affected by increasing Cr. The maximum temperature located close to the upper edge of battery is found to get reduced significantly with the increase of Cr , but upto a certain limit above which reduction is marginal. The analysis carried out reveals that Cr and Q gen have no role in improving Nu avg while Pr and Re vary it significantly in each step. Moreover, Nu avg is found to increase with Re continuously irrespective of any Cr and Q gen. While, for oils with an increase in Pr and Re , Nu avg was found to reduce significantly. Nanofluids are found to be more effective in improving heat transfer from the battery pack when cooled by flowing nano-coolants over it. The MBP networks proposed are successfully trained, and hence they can be used for prediction of Nu avg. • Conjugate numerical analysis of battery cells is carried for several coolants. • Multiple back propagation modelling of Nusselt number is carried. • Nanofluids provide maximum heat transfer. • Multiple feed forward with back propagation predicts Nusselt number properly. [ABSTRACT FROM AUTHOR]

Heat transfer and phase change flow inside a Li-ion battery enclosure filled with a copper metal foam embedded in paraffin wax phase change material (PCM) are studied numerically. For simplicity and due to the axisymmetric of the enclosure geometry, half of the battery cell is considered as the heat source on the right wall. The vertical walls are considered symmetric, while the bottom wall is insulated, and the top wall is subjected to the convective heat transfer. The governing equations of the flow and heat transfer are presented as partial differential equations and then transformed into non-dimensional forms and solved by employing the finite element method. The local thermal equilibrium model was used, which limits the model to metal foams with high pore densities. For validation, results are compared with some of the well-known studies in the literature. The isotherms and streamlines are presented for three levels of heat pulse intensity. Both melting and solidification occur as a result of the unsteady heat pulses induced by the thermal source. The vertical location of the battery inside the enclosure can affect the streamlines and isotherm contours. Results show that for higher heat pulse powers, the melt volume fraction (MVF) increases, and heatsink will have higher efficiency. For a comparatively strong heat pulse, the efficiency was increased about seven times. [ABSTRACT FROM AUTHOR]