Advanced Fundamental Studies on Supercritical Fluids

超临界流体高级基础研究

• 批准号: RGPIN-2016-05080
• 负责人: Pioro, Igor
• 金额: $ 1.89万
• 依托单位: University of Ontario Institute of Technology
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=662239
• 关键词: Advanced; Fundamental; Studies; Supercritical; Fluids

Supercritical fluids are fluids at pressures above a critical pressure (critical pressure and temperature are characteristics of a critical point in which the distinction between the liquid and vapour phases disappears, i.e., both phases have the same temperature, pressure and volume). Critical parameters for water are pressure of 22.1 MPa and temperature of 374 C; for carbon dioxide - 7.4 and 31 C; and for R-134a - 4.1 and 101 C; respectively. Supercritical fluids exhibit a unique set of properties, which allow to store a lot of energy during heating and retrieve this energy during cooling or during expansion through a turbine, which make them ideal working fluids or coolants for use in a variety of industrial and laboratory applications. The largest industrial application of supercritical fluids is the extensive use of supercritical water in power industry in supercritical-pressure coal-fired power plants, which have quite high thermal efficiency (up to 55%) compared to other power plants. However, there are many other areas of application for these fluids such as coolants in Generation-IV nuclear-reactor concepts (supercritical water and helium); in power cycles of these reactors (supercritical water, helium and carbon dioxide); etc.****Specifics of supercritical fluids' properties have significant impact on heat transfer and pressure drop at these conditions. Despite more than 60 years of active research into supercritical fluids, many of physical phenomena and behavioural characteristics are not fully understood (for example, improved and deteriorated heat-transfer regimes, pseudo-boiling, pseudo-film boiling, etc.). Solid knowledge and understanding of thermophysical properties and heat-transfer specifics at supercritical pressures are very important for a safe and efficient use of supercritical fluids in various industries. The applicant has made significant progress investigating specifics of supercritical fluids that have resulted in numerous publications and the first technical book on heat transfer and pressure drop at supercritical pressures. His latest heat-transfer correlation, developed together with his students, for supercritical water flowing in tubes is currently the most accurate one when compared to other correlations developed within the last 50 years. The proposed research, which will include analytical, numerical, Computational Fluid Dynamics (CFD) and experimental work, is based on his extensive expertise on properties and heat-transfer specifics of supercritical water, carbon dioxide, helium and freons and various industrial applications of these fluids including in Generation IV reactors. The objective of this research program is to broaden our knowledge of the fundamental behaviour and various phenomena in supercritical fluids and develop a scientific foundation for understanding parameters that govern behavior of these fluids.**

超临界流体是压力高于临界压力的流体（临界压力和温度是临界点的特征，其中液相和气相之间的区别消失，即，两相具有相同的温度、压力和体积）。水的临界参数分别为22.1 MPa和374 ℃;二氧化碳为7.4和31 ℃; R-134 a为4.1和101 ℃。超临界流体表现出一组独特的性质，其允许在加热期间存储大量能量，并且在冷却期间或在通过涡轮机膨胀期间回收该能量，这使它们成为用于各种工业和实验室应用的理想工作流体或冷却剂。超临界流体最大的工业应用是超临界水在电力工业中的广泛使用，超临界压力燃煤电厂与其他电厂相比具有相当高的热效率（高达55%）。然而，这些流体还有许多其他应用领域，例如第四代核反应堆概念中的冷却剂（超临界水和氦）;这些反应堆的动力循环（超临界水，氦和二氧化碳）等。超临界流体的特性对传热和压降有着重要的影响。尽管对超临界流体进行了60多年的积极研究，但许多物理现象和行为特征尚未完全理解（例如，改善和恶化的传热机制，伪沸腾，伪膜沸腾等）。对超临界压力下的热物理性质和传热特性的扎实了解和理解对于在各个行业中安全有效地使用超临界流体非常重要。申请人已经在研究超临界流体的细节方面取得了重大进展，这导致了大量出版物和第一本关于超临界压力下的传热和压降的技术书籍。他与学生们共同开发的最新传热相关性，与过去50年开发的其他相关性相比，目前是最准确的。拟议的研究将包括分析，数值，计算流体动力学（CFD）和实验工作，基于他对超临界水，二氧化碳，氦气和氟利昂的特性和传热特性以及这些流体的各种工业应用（包括第四代反应堆）的广泛专业知识。该研究计划的目的是扩大我们对超临界流体的基本行为和各种现象的了解，并为理解这些流体的行为参数奠定科学基础。