Purpose

The purpose of this paper is to investigate the impact of mechanical vibration on the heat transfer and pressure drop characteristics of semicircular channel printed circuit heat exchangers (PCHEs), while also establishing correlations between vibration parameters and thermal performance.

Design/methodology/approach

By combining experimental and numerical simulation methods, the heat transfer coefficient and pressure drop characteristics of supercritical carbon dioxide (S-CO₂) in a semicircular channel with a diameter of 2 mm under vibration conditions were studied. Reinforce the research by conducting computational fluid dynamics studies using ANSYS Fluent 22.0, the experimental results were compared with the numerical simulation results to verify the accuracy of the numerical method.

Findings

The use of vibration has the potential to attenuate the degradation of wall heat transfer caused by buoyancy-induced PCHEs on the upward-facing surface. The heat transfer enhancement (HTE) was maximized by an increase of 18.2%, while the pressure drop enhancement (PDE) was elevated by over 25-fold. The capacity to enhance the heat exchange between S-CO₂ and channel walls through increasing vibration intensity is limited, indicating maximum effectiveness in improving thermal performance.

Originality/value

Conducting heat transfer experiments on PCHEs with mechanical vibration enhancement and verifying the accuracy of the vibration numerical model. The relation based on the dimensionless factor is derived. To provide theoretical support for using vibration to enhance the heat transfer capability of PCHEs.

中文翻译：

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机械振动下印刷电路热交换器的传热特性

 目的

本文的目的是研究机械振动对半圆形通道印刷电路热交换器（PCHE）的传热和压降特性的影响，同时建立振动参数和热性能之间的相关性。

设计/方法论/途径

采用实验与数值模拟相结合的方法，研究了振动条件下超临界二氧化碳（S-CO ₂ ）在直径2 mm半圆形通道内的传热系数和压降特性。加强研究，利用ANSYS Fluent 22.0进行计算流体动力学研究，将实验结果与数值模拟结果进行对比，验证数值方法的准确性。

 发现

振动的使用有可能减弱由浮力引起的向上表面上的 PCHE 引起的壁传热退化。传热强化 (HTE) 最大化，增加了 18.2%，而压降强化 (PDE) 则提高了 25 倍以上。通过增加振动强度来增强S-CO ₂和通道壁之间的热交换的能力是有限的，这表明在改善热性能方面具有最大的有效性。

 原创性/价值

对机械振动增强的PCHE进行传热实验，验证振动数值模型的准确性。推导了基于无量纲因子的关系。为利用振动增强PCHE的传热能力提供理论支持。