Heating and cooling of fluids play an important role in energy engineering, such as solar air heaters and the internal cooling of gas turbine blades. Heat transfer in the heat exchanger channels can be enhanced by ribs, which will also result in a significant decrease in coolant pressure. In our previous work, a novel bioinspired rib design with a rhombus-shaped pattern was proposed to enhance the channel cooling. The Nusselt numbers and flow characteristics are further compared to angled and parallel broken ribs in this work. It is interesting to find that the proposed channel with decreasing-height rhombus-shaped patterned ribs exhibits the best heat transfer performance. At the same time, the Nusselt number and friction factor are related to the Reynolds number in the studied range. The surface with rhombus-shaped patterned ribs shows greater thermal performance factors than that with angled ribs, while the surface with a decreasing-height rib arrangement has the highest thermal performance factor due to a better Coanda effect. This work confirms that the proposed ribs with decreasing height rhombus-shaped patterns are effective for enhancing the internal cooling of the channel.

中文翻译：

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斜角、平行折断和菱形肋条增强通道冷却的比较研究

流体的加热和冷却在能源工程中发挥着重要作用，例如太阳能空气加热器和燃气轮机叶片的内部冷却。肋片可以增强热交换器通道中的传热，这也会导致冷却剂压力显着降低。在我们之前的工作中，提出了一种具有菱形图案的新型仿生肋设计来增强通道冷却。在这项工作中，努塞尔数和流动特性进一步与成角度和平行的断肋进行了比较。有趣的是，所提出的具有高度递减的菱形图案肋的通道表现出最佳的传热性能。同时，在研究范围内，努塞尔数和摩擦因数与雷诺数相关。具有菱形图案肋的表面比具有角度肋的表面表现出更大的热性能系数，而具有高度递减肋布置的表面由于更好的柯恩达效应而具有最高的热性能系数。这项工作证实了所提出的具有高度递减的菱形图案的肋对于增强通道的内部冷却是有效的。