Towards comprehensive multiphase flow modelling for nuclear reactor thermal hydraulics

核反应堆热工水力综合多相流建模

• 批准号: EP/S019871/2
• 负责人: Marco Colombo
• 金额: $ 12.51万
• 依托单位: University of Sheffield
• 依托单位国家: 英国
• 项目类别: Fellowship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FS019871%2F2
• 关键词: Towards; comprehensive; multiphase; flow; modelling

In any nuclear reactor, ensuring that the nuclear fuel always remains properly cooled is the main achievement of the thermal hydraulic design, which thus has utmost impact on the safety and the performance of the plant. Often, this thermal hydraulic design and the plant safety assessment rely on computational models that, by providing a mathematical representation of the physical system, predict the fluid dynamic behaviour of the coolant and the rate of heat transfer in the system. In a nuclear plant, in normal operating conditions or in accident scenarios that require emergency cooling, this often requires solving gas-liquid multiphase flow problems. Unfortunately, although computational tools of any degree of complexity are now available, modelling and computation of gas-liquid multiphase flows is still mainly limited to well-defined flow conditions and/or entirely based on empiricism. The aim of this fellowship is to develop an advanced computational model that overcomes these limitations and goes well-beyond currently available capabilities. At the present time, different techniques reach good accuracy in distinct and well-defined flow conditions, but none has been successful in modelling the entire spectrum of gas-liquid multiphase flows without a priori knowledge of the flow regime. This strongly limits the applicability of available models to flows that are of industrial interest, since these rarely exhibit the same well-characterized and defined flow features. In this project, by means of novel numerical techniques, advanced modelling methods will be coupled in the same computational model and selectively applied based on suitability to the local flow conditions. This will ensure accuracy and unprecedented applicability to multiphase gas-liquid flows, avoiding limiting assumptions but at the same time unrealistic computational requirements.In the nuclear sector, such a model will provide leading edge modelling and simulation capabilities, underpinning improved operation of the current reactor fleet and design and assessment of future plants. Confident predictions will inform the reactor design and the assessment of safety limits, reducing empiricism and conservatism. In addition, the number of costly experiments will be limited to a smaller number of model-driven tests. Reactors that are safer and produce electricity at a cheaper price and with a reduced waste footprint will underpin Government's plan for between 16 GW and 75 GW of new nuclear generation capacity by 2050. This new capacity will be essential to ensure a secure, sustainable and low-carbon energy future to the UK and respect the legally binding commitment to reduce carbon emission by 2050 of at least 80% with respect to 1990.In addition, the work will have wider application outside the nuclear sector in the optimization of the design and operation of the numerous industrial equipment exploiting gas-liquid multiphase flows across all branches of engineering (e.g. enhanced mixing by bubbles in bubble columns, fluid dispersion and mass transfer in separation equipment, two/three phase flow streams in extraction, treatment and transportation of oil and gas). At the same time, the fine resolution of spatial and temporal scales as well as of the majority of the interfacial details will allow more fundamental studies to be made. These will shed new light on the many aspects of multiphase flows that still miss thorough understanding, which negatively affects the design and operation of multiphase equipment. The project will benefit from close collaboration with esteemed academics within the UK and overseas (Massachusetts Institute of Technology and North Carolina State University) and industrial leaders in the development of computational products for the nuclear industry and in the analysis and assessment of nuclear reactor thermal hydraulics (Siemens Industry Software Ltd and Frazer-Nash Consultancy).

在任何核反应堆中，确保核燃料始终保持正确冷却是热液压设计的主要成就，因此，这对植物的安全性和性能产生了最大的影响。通常，这种热液压设计和植物安全评估依赖于计算模型，通过提供物理系统的数学表示，预测冷却剂的流体动态行为和系统中的热传递速率。在核电站，在正常工作条件或需要紧急冷却的事故情况下，这通常需要解决气体液体多相流量问题。不幸的是，尽管现在有任何复杂程度的计算工具，但气体液体多相流的建模和计算仍然主要限于定义明确的流动条件和/或完全基于经验主义。该奖学金的目的是开发一个高级计算模型，该模型克服了这些局限性，并在当前可用的功能中获得了良好的限制。目前，在不同的且定义明确的流动条件下，不同的技术达到了良好的准确性，但是在没有先验知识的流动状态的情况下，没有一个成功地对整个气体液体多相流进行建模。这很大程度上限制了可用模型在具有工业兴趣的流动中的适用性，因为这些模型很少表现出相同的特征和定义的流动特征。在该项目中，通过新颖的数值技术，高级建模方法将耦合在相同的计算模型中，并根据适用性对局部流动条件进行选择应用。这将确保对多相气体流动流的准确性和前所未有的适用性，避免限制假设，但同时却是不切实际的计算要求。在核部门，这种模型将提供领先的模型和仿真功能，从而提高了电流反应器的运行。舰队，设计和评估未来的植物。自信的预测将为反应堆设计和安全限制的评估提供信息，从而减少经验主义和保守主义。此外，昂贵的实验数量将仅限于较少的模型驱动测试。到2050年到2050年，以更便宜和发电的反应堆将支持政府在16吉瓦至75 GW的新核发电能力之间的计划。 - 英国的碳能源未来，并尊重在1990年至少80％之前将碳排放降低至少80％的法律约束力的承诺。此外，这项工作将在核部门以外更广泛地应用设计和运营。在工程的所有分支中利用气体液多相流的众多工业设备（例如，气泡柱中的气泡加强混合，流体分散和分离设备中的质量转移，两/三相流量流，在提取，处理和运输油以及油和运输中气体）。同时，空间和时间尺度以及大多数界面细节的精细分辨率将允许进行更多的基本研究。这些将为多相流的许多方面提供新的启示，这些流动仍然错过了彻底的理解，这对多相设备的设计和操作产生了负面影响。该项目将受益于与英国和海外尊敬的学者（马萨诸塞州技术学院和北卡罗来纳州立大学）的密切合作，以及工业领导者的核工业计算产品以及核反应堆热液压的分析和评估（西门子行业软件有限公司和Frazer-Nash咨询公司）。

项目成果

A Generalized Multifluid Modelling Approach (GEMMA): application to multiple flow regime phenomena in nuclear reactor thermal hydraulics.

广义多流体建模方法（GEMMA）：应用于核反应堆热工水力学中的多流态现象。

• 发表时间: 2022
• 作者: Colombo M.

Large eddy simulation for the modelling of the dynamic behaviour of the DYNASTY natural circulation loop

用于 DYNASTY 自然循环回路动态行为建模的大涡模拟

• 发表时间: 2022
• 作者: Battistini A.

A Review on the Modelling of Wave-Structure Interactions Based on OpenFOAM

• DOI: 10.51560/ofj.v2.65
• 发表时间: 2022-08
• 期刊: OpenFOAM® Journal
• 作者: Luofeng Huang;Yuzhu Li;Daniela Benites-Munoz;C. Windt;Anna Feichtner;S. Tavakoli;J. Davidson;R. Paredes;Tadea Quintuna;E. Ransley;M. Colombo;Minghao Li;P. Cardiff;G. Tabor

Prediction of Horizontal Gas-Liquid Segregated Flow Regimes with an All Flow Regime Multifluid Model

用全流态多流体模型预测水平气液分离流态

• DOI: 10.3390/pr10050920
• 发表时间: 2022
• 期刊: Processes
• 影响因子: 3.5
• 作者: Colombo M

A novel generalized multiphase modelling approach for the simulation of multiphase flows: model development and validation.

用于模拟多相流的新颖的广义多相建模方法：模型开发和验证。

• 发表时间: 2021
• 作者: Colombo M.