Energy, Exergy, and flow fields analysis to enhance performance potential of a heat-driven thermoacoustic refrigerator

IF 5.1 3区工程技术 Q2 ENERGY & FUELS

Thermal Science and Engineering Progress Pub Date : 2024-10-01 DOI:10.1016/j.tsep.2024.102938

Mahyar Fazli, Karim Mazaheri

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Abstract

This study focuses on the design, optimization, and analysis of a heat-driven thermoacoustic refrigerator system to be used in a medium-size Combined Heat and Power (CHP) system, using its exhaust hot gases. Two configurations are investigated to maximize the total Coefficient of Performance (

{C O P}_{T o t}

). Several approaches, including energy, sensitivity, displacement, and exergy analyses were conducted to understand the underlying physics, identify more effective performance configurations, and to find areas with the most potential for improvements. In an energy analysis, the engine and resonator efficiency, and the refrigerator COP (

{C O P}_{R F}

) were examined. The effects of engine and refrigerator stacks and their heat exchanger lengths and spacings on engine efficiency and the

{C O P}_{T o t}

were investigated. Work and heat transfer dynamics are investigated across the system. Component interactions were explored through studying the acoustic intensity and pressure and velocity phase difference (

θ_{P U}

) distribution, and variations in velocity and pressure amplitudes in the engine and refrigerator stacks. Displacement analysis was introduced to assess the impact of stack length variations on refrigerator and engine displacement amplitudes. The analysis revealed the significant influence of the hot heat exchanger in the engine (HHX_e) and the cold heat exchanger in the refrigerator (CHX_RF) on design optimality. Sensitivity analysis identifies that the performance indices of the refrigerator are mainly sensitive to the stack length and spacing. Additionally, based on three new performance indices, an exergy analysis identified why and how the refrigerator heat exchanger closest to the engine performs better.

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能量、Exergy 和流场分析，提升热驱动热声冰箱的性能潜力

本研究的重点是设计、优化和分析中型热电联产（CHP）系统中使用的热驱动热声制冷系统，并利用其排出的热气。研究了两种配置，以最大限度地提高总性能系数（COPTot）。为了了解基本物理原理，确定更有效的性能配置，并找到最具改进潜力的领域，我们采用了多种方法，包括能量、灵敏度、排量和放能分析。在能量分析中，研究了发动机和谐振器的效率以及冰箱的 COP（COPRF）。还研究了发动机和制冷机堆栈及其热交换器长度和间距对发动机效率和 COPTot 的影响。研究了整个系统的功和热传递动态。通过研究声强、压力和速度相位差 (θPU)分布，以及发动机和冰箱烟囱中速度和压力振幅的变化，探讨了各组成部分之间的相互作用。还引入了位移分析，以评估堆栈长度变化对冰箱和发动机位移振幅的影响。分析表明，发动机中的热交换器（HHXe）和制冷机中的冷热交换器（CHXRF）对设计优化有重大影响。敏感性分析表明，制冷机的性能指标主要对堆栈长度和间距敏感。此外，基于三个新的性能指标，放能分析确定了最靠近发动机的冰箱热交换器性能更好的原因和方式。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Thermal Science and Engineering Progress Chemical Engineering-Fluid Flow and Transfer Processes

CiteScore

7.20

自引率

10.40%

发文量

327

审稿时长

41 days

期刊介绍： Thermal Science and Engineering Progress (TSEP) publishes original, high-quality research articles that span activities ranging from fundamental scientific research and discussion of the more controversial thermodynamic theories, to developments in thermal engineering that are in many instances examples of the way scientists and engineers are addressing the challenges facing a growing population – smart cities and global warming – maximising thermodynamic efficiencies and minimising all heat losses. It is intended that these will be of current relevance and interest to industry, academia and other practitioners. It is evident that many specialised journals in thermal and, to some extent, in fluid disciplines tend to focus on topics that can be classified as fundamental in nature, or are ‘applied’ and near-market. Thermal Science and Engineering Progress will bridge the gap between these two areas, allowing authors to make an easy choice, should they or a journal editor feel that their papers are ‘out of scope’ when considering other journals. The range of topics covered by Thermal Science and Engineering Progress addresses the rapid rate of development being made in thermal transfer processes as they affect traditional fields, and important growth in the topical research areas of aerospace, thermal biological and medical systems, electronics and nano-technologies, renewable energy systems, food production (including agriculture), and the need to minimise man-made thermal impacts on climate change. Review articles on appropriate topics for TSEP are encouraged, although until TSEP is fully established, these will be limited in number. Before submitting such articles, please contact one of the Editors, or a member of the Editorial Advisory Board with an outline of your proposal and your expertise in the area of your review.