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Go to Editorial ManagerNumerical analysis of transient laminar three- dimensional buoyancy-driven convection in an inclined three- dimensional trapezoidal air-filled enclosure was investigated in this paper. The right and left sidewalls of the enclosure are kept at constant cold temperatures. The bottom wall is maintained at a constant hot temperature , while the top wall is considered adiabatic. Numerical investigation is performed for Rayleigh numbers varied as 10 3 ≤ Ra ≤ 10 5 , while the trapezoidal enclosure inclination angle is varied as 0° ≤ ≤ 180°. Prandtl number is considered constant at Pr = 0.71. Flow and thermal fields are presented in both two and three- dimensional pattern. Also, both local and average Nusselt numbers are calculated and discussed. The results show that when the Rayleigh number increases, the flow patterns are changed especially in three-dimensional results and the flow circulation increases. The minimum average Nusselt number inside the trapezoidal cavity corresponds to the highest 180 ].While, the average Nusselt inclination angle [i.e., 30 . Moreover, number reaches its maximum value at when the Rayleigh number increases the average Nusselt number increases as expected.
The thermoelectric behavior of different materials under various conditions has been investigated numerically by using the heat transfer module of the COMSOL Multiphysics software platform. A simulation study of the thermoelectric materials (TEM) performance was created by altering the current applied from 0.1 to 1.0 A and setting the hot side temperature (T H ) as 273 K. The impact of different performance metrics, such as cold side temperature and output voltage, has been proven and investigated. It has been shown that the material of the thermoelectric legs', length of leg, and thickness of electrodes significantly impact the thermal and electrical performance of the thermoelectric (TE) module. Appropriate ranges have been studied in the simulation, such as the amperage values applied to the unit as mentioned above, the length of the leg within a range of 1 to 8 mm, and the thickness of the electrode with different values of 0.1 to 0.5 mm, which will achieve excellent performance for the Thermoelectric unit. Modeling and simulation results demonstrated and revealed the optimal and potential use of bismuth telluride (Bi 2 Te 3 ) as well as lead telluride (PbTe) as suitable for Peltier cooling applications. As for the use of cobalt triantimonide (CoSb 3 ), it is in contrast to the two previous metals, as it is effective and appropriate if applied to power generation. The results are validated with another study from the literature, and there is an excellent agreement with an error rate that does not exceed 0.164%.