A MOPSO-based design optimization on molten salt steam generator forced circulation system under off-design conditions

IF 2.6 3区工程技术 Q2 ENGINEERING, MECHANICAL

International Journal of Heat and Fluid Flow Pub Date : 2024-11-17 DOI:10.1016/j.ijheatfluidflow.2024.109659

Jiaming Tian, Biao Li, Bo Ren, Yueshe Wang

{"title":"A MOPSO-based design optimization on molten salt steam generator forced circulation system under off-design conditions","authors":"Jiaming Tian, Biao Li, Bo Ren, Yueshe Wang","doi":"10.1016/j.ijheatfluidflow.2024.109659","DOIUrl":null,"url":null,"abstract":"<div><div>The concentrating solar power (CSP) technologies have been demonstrated their effectiveness in providing ancillary services for peak regulation in power systems with high penetration of renewable energy. Investigating control mechanisms of a forced circulation mode applied in the steam generator, which a shell-and-tube heat exchanger, in the CSP plant is imperative for swift adaptation to its off-design operating conditions. This study aims to develop a predictive model for the hydrodynamics of a molten salt steam generator in a forced circulation mode, integrating heat transfer and phase change through the lumped parameter method. Additionally, a solution approach is proposed based on multi-objective particle swarm optimization (MOPSO) to achieve thermal-economic optimization designs of the steam generator under varying off-design conditions. Optimization analyses are conducted separately for the constant load and the off-design conditions, considering variables such as molten salt flow rate, steam-water circulation flow rate, number of baffles, and tube diameter of the heat exchanger. The results reveal that during the prolonged operation at low evaporation rates, employing an evaporator with more baffles and a larger tube diameter of 20 mm leads to favorable outcomes. Conversely, meticulous design considerations are imperative when planning for sustained high evaporation rates due to the significant impact of the number of baffles on both efficiency and economic costs. At a load of 215 t/h, the adding of two baffles results in an approximate increase of $20 million in operational costs by nearly and an improvement in efficiency by 0.01. Additionally, a fitting formula is provided to offer recommendations on optimal mass flow rates that maximize effectiveness and minimize economic costs for varying evaporation demands under off-design conditions, thereby assisting engineers in optimizing peak regulation operations.</div></div>","PeriodicalId":335,"journal":{"name":"International Journal of Heat and Fluid Flow","volume":"110 ","pages":"Article 109659"},"PeriodicalIF":2.6000,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Heat and Fluid Flow","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0142727X24003849","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, MECHANICAL","Score":null,"Total":0}

引用次数: 0

Abstract

The concentrating solar power (CSP) technologies have been demonstrated their effectiveness in providing ancillary services for peak regulation in power systems with high penetration of renewable energy. Investigating control mechanisms of a forced circulation mode applied in the steam generator, which a shell-and-tube heat exchanger, in the CSP plant is imperative for swift adaptation to its off-design operating conditions. This study aims to develop a predictive model for the hydrodynamics of a molten salt steam generator in a forced circulation mode, integrating heat transfer and phase change through the lumped parameter method. Additionally, a solution approach is proposed based on multi-objective particle swarm optimization (MOPSO) to achieve thermal-economic optimization designs of the steam generator under varying off-design conditions. Optimization analyses are conducted separately for the constant load and the off-design conditions, considering variables such as molten salt flow rate, steam-water circulation flow rate, number of baffles, and tube diameter of the heat exchanger. The results reveal that during the prolonged operation at low evaporation rates, employing an evaporator with more baffles and a larger tube diameter of 20 mm leads to favorable outcomes. Conversely, meticulous design considerations are imperative when planning for sustained high evaporation rates due to the significant impact of the number of baffles on both efficiency and economic costs. At a load of 215 t/h, the adding of two baffles results in an approximate increase of $20 million in operational costs by nearly and an improvement in efficiency by 0.01. Additionally, a fitting formula is provided to offer recommendations on optimal mass flow rates that maximize effectiveness and minimize economic costs for varying evaporation demands under off-design conditions, thereby assisting engineers in optimizing peak regulation operations.

查看原文本刊更多论文

非设计条件下基于 MOPSO 的熔盐蒸汽发生器强制循环系统优化设计

聚光太阳能发电（CSP）技术在为可再生能源渗透率较高的电力系统提供调峰辅助服务方面的有效性已得到证实。为了迅速适应非设计运行条件，研究 CSP 电站蒸汽发生器（管壳式热交换器）强制循环模式的控制机制势在必行。本研究旨在为强制循环模式下的熔盐蒸汽发生器建立流体力学预测模型，通过集合参数法整合传热和相变。此外，还提出了一种基于多目标粒子群优化（MOPSO）的求解方法，以实现蒸汽发生器在不同非设计条件下的热经济优化设计。考虑到熔盐流速、蒸汽-水循环流速、挡板数量和换热器管径等变量，分别对恒定负荷和非设计工况进行了优化分析。结果表明，在低蒸发率的长时间运行中，采用具有更多挡板和更大管径（20 毫米）的蒸发器会带来有利的结果。相反，由于挡板数量对效率和经济成本都有显著影响，因此在规划持续高蒸发率时，必须进行细致的设计考虑。在负荷为 215 吨/小时的情况下，增加两块挡板可使运营成本增加近 2000 万美元，效率提高 0.01。此外，还提供了一个拟合公式，针对非设计条件下的不同蒸发需求，提出了最佳质量流量的建议，以实现效率最大化和经济成本最小化，从而帮助工程师优化调峰操作。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

International Journal of Heat and Fluid Flow 工程技术-工程：机械

CiteScore

5.00

自引率

7.70%

发文量

131

审稿时长

33 days

期刊介绍： The International Journal of Heat and Fluid Flow welcomes high-quality original contributions on experimental, computational, and physical aspects of convective heat transfer and fluid dynamics relevant to engineering or the environment, including multiphase and microscale flows. Papers reporting the application of these disciplines to design and development, with emphasis on new technological fields, are also welcomed. Some of these new fields include microscale electronic and mechanical systems; medical and biological systems; and thermal and flow control in both the internal and external environment.