Improvements to CTF for Modeling of Boiling Water Reactor Geometry and Operating Conditions

The experiments were performed on the test loop HRTL-5, which simulates geometry and system design of the 5-MW Nuclear Heating Reactor developed by the Institute of Nuclear Energy Technology, Tsinghua University. Because of the difference of the geometry design and operating conditions between the heating reactor and the boiling water reactor, the flow behavior presents great differences too, some of which haven’t been deeply studied so far. Results show that in heating reactor, sub-cooled boiling, condensation and flashing play an important role on the flow instabilities of the natural circulation system. Correspondingly, geysering instability, flashing instability, and flow excursion are the very typical instabilities occurring in the primary loop of HRTL-5, which are different from those in boiling water reactor conditions. The compressibility of the steam space on the top of the primary loop has also great influence on the instability of the natural circulation system.

Download Full-text

Electrochemical Impedance Study of Zirconium under Simulated Boiling Water Reactor Operating Conditions

ECS Meeting Abstracts ◽

10.1149/ma2006-01/34/1176 ◽

2006 ◽

Keyword(s):

Electrochemical Impedance ◽

Operating Conditions ◽

Boiling Water ◽

Boiling Water Reactor ◽

Water Reactor ◽

Impedance Study ◽

Reactor Operating

Download Full-text

Development and Validation of a Computational Fluid Dynamics Model for the Simulation of Two-Phase Flow Phenomena in a Boiling Water Reactor Fuel Assembly

Volume 5: Fuel Cycle and High and Low Level Waste Management and Decommissioning; Computational Fluid Dynamics (CFD), Neutronics Methods and Coupled Codes; Instrumentation and Control ◽

10.1115/icone17-75135 ◽

2009 ◽

Author(s):

Adrian Tentner ◽

W. David Pointer ◽

Simon Lo ◽

Andrew Splawski

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Two Phase Flow ◽

Operating Conditions ◽

Boiling Water ◽

Boiling Water Reactor ◽

Phase Flow ◽

Two Phase ◽

Water Reactor ◽

Development And Validation

This paper presents the current status in the development and validation of an advanced Computational Fluid Dynamics (CFD) model, CFD-BWR, which allows the detailed analysis of the two-phase flow and heat transfer phenomena in Boiling Water Reactor (BWR) fuel assemblies under various operating conditions. The CFD-BWR model uses an Eulerian Two-Phase (E2P) approach, and is also referred to as the E2P modeling framework. It is being developed as a customized module built on the foundation of the commercial CFD-code STAR-CD which provides general two-phase flow modeling capabilities. The integral validation efforts have focused on the analysis of the NUPEC Full-Size Boiling Water Reactor Test (BFBT) within the framework of the OECD/NRC benchmark exercise. The paper reviews the two-phase models implemented in the CFD-BWR code, and emphasizes recently implemented models of inter-phase and coolant-cladding momentum and energy exchanges. Results of recent BFBT experiment simulations using these models are presented and the effects of the new models on the calculated void distribution are discussed. The paper concludes with a discussion of future model development and validation plans.

Download Full-text