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Fuel variability plays a major role in biogas combustion utilisation, where modelling and simulation can be used to provide guidelines. The construction of a flamelet generated manifold (FGM) is an important step for the simulation of complex turbulent flames. The FGM is made from premixed laminar flames and the limited literature on biogas combustion has led to this study on the effects of the fuel composition on biogas combustion in a freely propagating laminar premixed flame. The results have shown that methane concentration has a significant impact on the combustion process. There was no major difference observed among fuel mixtures with a fixed CH 4 volume concentration of 50%, with CO 2 varied from 40%, 49% to 50% and completed with either 10% of N 2 or 1% H 2 . The study can be further extended for numerical simulations under more realistic and practical conditions in order to develop guidelines for industrial combustors.

Lithium-ion (Li-ion) battery cooling using a phase change material (PCM)/compressed expanded natural graphite (CENG) composite is investigated, for a cylindrical battery cell and for a battery module scale. An electrochemistry model (average model) is coupled to the thermal model, with the addition of a one-dimensional model for the solution and solid diffusion using the nodal network method. The analysis of the temperature distribution of the battery module scale has shown that a two-dimensional model is sufficient to describe the transient temperature rise. In consequence, a two-dimensional cell-centred finite volume code for unstructured meshes is developed with additions of the electrochemistry and phase change. This two-dimensional thermal model is used to investigate a new and usual battery module configurations cooled by PCM/CENG at different discharge rates. The comparison of both configurations with a constant source term and heat generation based on the electrochemistry model showed the superiority of the new design. In this study, comparisons between the predictions from different analytical and computational tools as well as open-source packages were carried out, and close agreements have been observed.

The thermal management of a cylindrical battery cell by a phase change material (PCM)/compressed expanded natural graphite (CENG) is investigated in this study. The transient thermal behaviour of both the battery and the PCM/CENG is described with a simplified one-dimensional model taking into account the physical and phase change properties of the PCM/CENG composite. The 1D analytical/computational model yielded nearly identical results to the three-dimensional simulation results for various cooling strategies. Therefore, the 1D model is sufficient to describe the transient behaviour of the battery cooled by a PCM/CENG composite. Moreover, the maximum temperature reached by the PCM/CENG cooling strategy is much lower than that by the forced convection in the same configuration. In the test case studied, the PCM showed superior transient characteristics to forced convection cooling. The PCM cooling is able to maintain a lower maximum temperature during the melting process and to extend the transient time for temperature rise. Furthermore, the graphite-matrix bulk density is identified as an important parameter for optimising the PCM/CENG cooling strategy.

A simplified one-dimensional transient computational model of a prismatic lithium-ion battery cell is developed using thermal circuit approach in conjunction with the thermal model of the heat pipe. The proposed model is compared to an analytical solution based on variable separation as well as three-dimensional (3D) computational fluid dynamics (CFD) simulations. The three approaches, i.e. the 1D computational model, analytical solution, and 3D CFD simulations, yielded nearly identical results for the thermal behaviours. Therefore the 1D model is considered to be sufficient to predict the temperature distribution of lithium-ion battery thermal management using heat pipes. Moreover, a maximum temperature of 27.6 °C was predicted for the design of the heat pipe setup in a distributed configuration, while a maximum temperature of 51.5 °C was predicted when forced convection was applied to the same configuration. The higher surface contact of the heat pipes allows a better cooling management compared to forced convection cooling. Accordingly, heat pipes can be used to achieve effective thermal management of a battery pack with confined surface areas.

Takotsubo syndrome is characterized by transient and regional left ventricular dysfunction, which does not correspond anatomically to coronary distribution, without obstructive coronary lesions and frequently follows episodes of emotional or physical stress. The authors present a case of takotsubo syndrome, complicated by acute heart failure and functional severe mitral regurgitation, in a newborn after fetal distress caused by the umbilical cord being twisted around the chest and neck. In newborns after birth asphyxia, left ventricular dysfunction has been reported as global and due to ischemia. In this case, the transient and regional left ventricular dysfunction involving segments of multiple epicardial coronary territories, with associated hyperkinesis of the ventricular septum and basal segments of other walls, could have been caused by delivery stress with catecholamine-mediated cardiac toxicity.