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This study analyzes how anode thickness and working temperature affect heat/mass transport characteristics and cell performance of the anode-supported SOFC button cell by the finite-volume SIMPLE-C method coupled with preconditioned conjugate gradient methods. The numerical results of this work are compared with the experimental data and good agreement is observed. The simulation is carried out for various anode thicknesses (0.1, 0.5, and 1.0 mm) and working temperatures (873, 1073, and 1273 K). The results showed that the cell performance reduces about 5.05% as the anode thickness is increased from 0.1 mm to 1.0 mm; however, the influence of anode thickness on the heat/mass transport phenomenon is slight because the geometric size of anode thickness is tiny for the whole SOFC. In addition, the cell performance increases about 50.54% as the working temperature is increased from 873 K to 1273 K. A higher working temperature enhances the fluid velocity and convection and consequently promotes the chemical reaction and obtains a better cell performance.

Phase change materials have been overwhelmingly used for thermal energy storage applications. Among organics, fatty acids are an important constituent of latent heat storage. Most of the saturated fatty acid PCMs so far studied are either unary or binary constituents of pure fatty acids. In the present study, ternary blends of saturated fatty acids i.e., capric, lauric, myristic, stearic, and palmitic acids have been developed with different weight proportions. A series of 28 ternary blends viz. CA-LA-MA, CA-LA-PA, CA-LA-SA, CA-MA-PA, CA-MA-SA, and CA-PA-SA were prepared and analyzed with differential scanning calorimetry, thermal gravimetric analysis, and Fourier transform infrared spectroscopy. DSC analysis revealed that the prepared materials lie in the 15–30 °C temperature range. Also, 300 thermal melt/freeze cycles were conducted which showed ±10% variation in terms of the melting peak for most of the PCMs, with the average latent heat of fusion between 130 and 170 kJ/kg. The TGA analysis showed that most of the PCMs are thermally stable up to 100 °C and useful for medium-low storage applications, and FTIR analysis showed that the materials are chemically stable after repeated thermal cycles. Based on cycle test performances, the developed materials were found to be reliable for long-term use in building and photovoltaic applications.

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The purpose of this paper is to create a rapid temperature balancing container which can firstly absorb heat from the stored thing to change its temperature within minutes into a desired value set by the melting temperature and type of the used phase change materials (PCMs), and then keep that temperature last longer as the absorbed heat is later released. Models in different geometrical shapes using a commercial PCM, called PW-70, with melting temperature of 70 o C have been made and tested carefully in laboratory. The best results of the four tested models, derived from the multi-layer model, have shown that average temperature of the boiled water which was acting as the stored substance reached the desired range of 55 ~ 65 o C within only about 15 minutes and this temperature range lasted within nearly 5 hours. It is also shown that this period is even much longer if the desired temperature value is lower. This is a big advantage compared with the vacuum container without PCM in which the desired range was reached after about 4 hours but lasted for only more than 2 hours. With this good performance, the new design has shown much more effective utilization of heat energy in food or beverage preservation purpose.