Abstract The role of multiple discrete solar heaters have been studied for energy efficiency in the heating of fluids. Current work involves natural convection studies with the various locations of the double heat sources along each side wall of the triangular-design 1 (regular isosceles triangle), triangular-design 2 (inverted isosceles triangle) and square enclosures for various cases (case 1: larger heater in lower half and smaller heater in central half, case 2: larger heater in central half and smaller heater in lower half, case 3: two heaters of identical lengths are located at the central and lower halves) involving various fluids ( P r = 0.015 and 7.2) for various Rayleigh numbers, 10 3 ≤ R a ≤ 10 5 . The thermal mixing and energy flow in the cavities are visualized using the mathematical tool of heatlines. Also, the overall rate of heat transfer in conduction and convection dominant regimes is evaluated using Nusselt numbers (average and local). The case 2 discrete heating configuration is inferred as the optimal heating configuration based on the larger zone of uniform temperature and thermal mixing. Also, the thermal management is significantly improved in triangular-design 2 and square cavities.

中文翻译：

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在方形和三角形腔体的自然对流过程中，多个太阳能加热器沿墙壁的热管理作用

摘要 为了提高流体加热的能效，研究了多个离散太阳能加热器的作用。当前的工作涉及自然对流研究，沿着三角形设计 1（正等腰三角形）、三角形设计 2（倒等腰三角形）和各种情况下的方形外壳（案例 1：下半部较大的加热器和中部半部较小的加热器，案例 2：中部较大的加热器和下半部较小的加热器，案例 3：两个相同长度的加热器位于中部和下半部），涉及各种流体（P r = 0.015 和 7.2) 对于各种瑞利数，10 3 ≤ R a ≤ 10 5 。空腔中的热混合和能量流可以使用热线数学工具进行可视化。还，使用 Nusselt 数（平均和局部）评估传导和对流主导区域的总传热速率。情况 2 离散加热配置被推断为基于均匀温度和热混合的较大区域的最佳加热配置。此外，三角形设计 2 和方形腔体的热管理得到显着改善。