scholarly journals Analysis on passive residual heat removal system with heat pipes for longterm decay heat removal of small lead-based reactor

2021 ◽  
Vol 236 ◽  
pp. 01018
Author(s):  
Chongju Hu ◽  
Wangli Huang ◽  
Zhizhong Jiang ◽  
Qunying Huang ◽  
Yunqing Bai ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Heat Removal ◽  
Heat Pipes ◽  
Decay Heat ◽  
The Core ◽  
Accident Condition ◽  
Computational Fluid Dynamics Cfd ◽  
Heat Removal System ◽  
Removal System ◽  
Residual Heat

.A lead-based reactor with employing heat pipes as passive residual heat removal system (PRHRS) for longterm decay heat removal was designed. Three-dimensional computational fluid dynamics (CFD) software FLUENT was adopted to simulate the thermal-hydraulic characteristics of the PRHRS under Station-Black-Out (SBO) accident condition. The results showed that heat in the core could be removed smoothly by the PRHRS, and the core temperature difference is less than 20 K.

CFD Investigation of Thermal-Hydraulic Behaviors in Full Reactor Core for Sodium-Cooled Fast Reactor

2018 ◽  
Author(s):  
Jing Chen ◽  
Dalin Zhang ◽  
Suizheng Qiu ◽  
Kui Zhang ◽  
Mingjun Wang ◽  
...  
Keyword(s):  
Fast Reactor ◽  
Power Distribution ◽  
Three Dimensional ◽  
Reactor Core ◽  
Heat Removal ◽  
The Core ◽  
Computational Fluid Dynamics Cfd ◽  
Heat Removal System ◽  
China Experimental Fast Reactor ◽  
Full Core

As the first developmental step of the sodium-cooled fast reactor (SFR) in China, the pool-type China Experimental Fast Reactor (CEFR) is equipped with the openings and inter-wrapper space in the core, which act as an important part of the decay heat removal system. The accurate prediction of coolant flow in the reactor core calls for complete three-dimensional calculations. In the present study, an investigation of thermal-hydraulic behaviors in a 180° full core model similar to that of CEFR was carried out using commercial Computational Fluid Dynamics (CFD) software. The actual geometries of the peripheral core baffle, fluid channels and narrow inter-wrapper gap were built up, and numerous subassemblies (SAs) were modeled as the porous medium with appropriate resistance and radial power distribution. First, the three-dimensional flow and temperature distributions in the full core under normal operating condition are obtained and quantitatively analyzed. And then the effect of inter-wrapper flow (IWF) on heat transfer performance is evaluated. In addition, the detailed flow path and direction in local inter-wrapper space including the internal and outlet regions are captured. This work can provide some valuable understanding of the core thermal-hydraulic phenomena for the research and design of SFRs.

Transient Study on Sodium Heat Pipe in Passive Heat Removal System of Molten Salt Reactor

2013 ◽  
Author(s):  
Chenglong Wang ◽  
Suizheng Qiu ◽  
Wenxi Tian ◽  
Yingwei Wu ◽  
Guanghui Su
Keyword(s):  
High Temperature ◽  
Molten Salt ◽  
Heat Pipe ◽  
Heat Removal ◽  
Heat Pipes ◽  
Molten Salt Reactor ◽  
Sodium Heat Pipe ◽  
Heat Removal System ◽  
Removal System ◽  
Residual Heat

High temperature heat pipes are effective devices for heat transfer, which are characterized by remarkable advantages in conductivity, isothermality and passivity. It is of significance to apply heat pipes on new concept passive residual heat removal system (PRHRS) of molten salt reactor (MSR). In this paper, the transient performance of high temperature sodium heat pipe is simulated with numerical method in the case of MSR accident. The model of the heat pipe is composed of three conjugate heat transfers, i.e. the vapor space, wick structure and wall. Based on finite element method, the governing equations and boundary conditions are solved by using FORTRAN code to acquire the profiles of the temperature, velocity and pressure for the heat pipe transient operation. The results indicated that high temperature sodium heat pipe had a good operating characteristic and removed the residual heat of fuel salt rapidly under the accident of MSR.

scholarly journals Effect of heat pipe failure on performance of residual heatremoval system with heat pipe for small lead-based reactor

2021 ◽  
Vol 248 ◽  
pp. 01021
Author(s):  
Chongju Hu ◽  
Hongyan Wang ◽  
Bo Wu ◽  
Xiuxiang Zhang ◽  
Pinghua Zhang
Keyword(s):  
Heat Pipe ◽  
Waste Heat ◽  
Heat Removal ◽  
Heat Pipes ◽  
Normal Operation ◽  
Pipe Failure ◽  
The Core ◽  
External Power ◽  
Heat Removal System ◽  
Removal System

Heat pipe have the characteristics of high thermal conductivity, high safety performance, without external power, etc. In this paper, The numerical simulation CFD software FLUENT is used to study the thermal-hydraulic characteristics performance of heat pipe waste heat removal system with heat pipe for lead-based reactor under normal conditions and Station-Black-Out (SBO) with partial heat pipes damage respectively. Results showed that heat pipes promote heat transfer in the reactor and reduced the temperature of the fluid around the reactor during normal operation; Heat in the core could be removed smoothly by the PRHRS during SBO accident without heat pipe damage ; and when the proportion of failed heat pipes is less than 50% during SBO accident , the PRHRS could still ensure safe operation of the reactor and the distribution of failed heat pipes in the reactor results the core temperature variation by less than 5 K.

scholarly journals CFD Analysis of the Passive Decay Heat Removal System of an LBE-Cooled Fast Reactor

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Jiarun Mao ◽  
Lei Song ◽  
Yuhao Liu ◽  
Jiming Lin ◽  
Shanfang Huang ◽  
...  
Keyword(s):  
Heat Exchange ◽  
Fast Reactor ◽  
Natural Circulation ◽  
Heat Removal ◽  
Engineering Project ◽  
Decay Heat ◽  
The Core ◽  
Main Vessel ◽  
Heat Removal System ◽  
Removal System

This paper presents capacity of the passive decay heat removal system (DHRS) operated under the natural circulation conditions to remove decay heat inside the main vessel of the Lead-bismuth eutectic cooled Fast Reactor (LFR). The motivation of this research is to improve the inherent safety of the LFR based on the China Accelerator Driven System (ADS) engineering project. Usually the plant is damaged due to the failure of the main pumps and the main heat exchangers under the Station Blackout (SBO). To prevent this accident, we proposed the DHRS based on the diathermic oil cooling for the LFR. The behavior of the DHRS and the plant was simulated using the CFD code STAR CCM+ using LFR with DHRS. The purpose of this analysis is to evaluate the heat exchange capacity of the DHRS and is to provide the reference for structural improvement and experimental design. The results show that the stable natural circulations are established in both the main vessel and the DHRS. During the decay process, the heat exchange power is above the core decay heat power. In addition, in-core decay heat and heat storage inside the main vessel are efficiently removed. All the thermal-hydraulics parameters are within a safe range. Moreover, the highest temperature occurs at the upper surface of the core. A swirl occurs at the corner of the lateral core surface and some improvements should be considered. And the natural circulation driving force can be further increased by reducing the loop resistance or increasing the natural circulation height based on the present design scenario to enhance the heat exchange effect.

Transient Analyses of Passive Residual Heat Removal System of 10MW Molten Salt Reactor Experiment

2014 ◽  
Vol 953-954 ◽  
pp. 621-626
Author(s):  
Hang Bin Zhao ◽  
Chang Qi Yan ◽  
Li Cheng Sun ◽  
Kai Bin Zhao
Keyword(s):  
Molten Salt ◽  
Power Plants ◽  
Heat Removal ◽  
Molten Salt Reactor ◽  
Inherent Safety ◽  
Decay Heat ◽  
Reactor Experiment ◽  
Heat Removal System ◽  
Removal System ◽  
Residual Heat

In order to improve the inherent safety of the Molten Salt Reactor (MSR), a concept of passive residual heat removal system (PRHRS) for the 10MW Molten Salt Reactor Experiment (MSRE) was put forward. Its transient characteristics were investigated by developing a model of it using C++ code. The effects of environmental temperature, finned tube number and chimney height on the PRHRS were analyzed. The results show that the PRHRS can remove the decay heat timely. Three natural circulations are established in the PRHRS when it begins to operate. With the decay heat power reducing, the PRHRS can automatically adjust its heat removal ability. It needs not any external power for the PRHRS to operate, which enhances the inherent safety and reliability of the reactor, especially under the condition that power plants lose power.

Experimental Research on Characteristics of Passive Residual Heat Removal System for Small Modular Reactors Under the Station Blackout Accident

2016 ◽  
Author(s):  
Xiaodong Lu ◽  
Chuanxin Peng ◽  
Yan Zhang ◽  
Xuesong Bai ◽  
Yuanfeng Zan ◽  
...  
Keyword(s):  
Experimental Research ◽  
Heat Removal ◽  
Injection System ◽  
Primary System ◽  
Water Tank ◽  
The Core ◽  
Station Blackout ◽  
Heat Removal System ◽  
Removal System ◽  
Residual Heat

An experimental research on performance characteristics of passive residual heat removal system (PRHRS) for the small modular reactor designed by Nuclear Power Institute of China (NPIC) under the station blackout accident was performed in the CREAS facility, which consists of the primary system, the secondary system, the passive safety injection system, the passive residual heat removal system, the overpressure protection system and the auxiliary system. The experimental results show that, after the station blackout accident, a stable two-phase natural circulation between the steam generators and the heat exchanger in the PRHRS was established with a mass flow of 0.4T/h, thus the heat from the primary system was removed to the water in the containment water tank (CWT). During this period, the core decay residual heat and the sensible heat were removed from the primary system by the PRHRS effectively. The cold water from the core makeup tanks was injected into the reactor pressure vessel for core cooling. The peaked primary pressure was 16.3MPa and less than relief valve opening pressure 16.9MPa. In addition, the average coolant temperature of the reactor core reduced below 483 K, and the reactor operated safely.

Transient Analysis of Passive Decay Heat Removal System for CEFR

2013 ◽  
Author(s):  
H. Qian ◽  
Z. Li ◽  
L. Ren
Keyword(s):  
Steady State ◽  
Transient Analysis ◽  
Heat Removal ◽  
Transfer System ◽  
Thermal Transfer ◽  
Decay Heat ◽  
The Core ◽  
Calculation Results ◽  
Heat Removal System ◽  
Removal System

A passive decay heat removal system (DHRS) has been installed on Chinese Experimental Fast Reactor (CEFR). To well predict the thermal-hydraulics behavior of DHRS in transient, an integrated model has been developed for CEFR by using OASIS code. The model included the main thermal transfer system and DHRS circuit. The transient analysis of loss of off-site power (LOSP) accident with various initial steady states has been performed. The calculation results show that the initial steady state does not essentially effect on the peak cladding temperature in the core.

scholarly journals CFD Analysis of the ESFR Reactor Pit Cooling System in Case of Sodium Leakage

2021 ◽  
Author(s):  
Aleksander Grah ◽  
Haileyesus Tsige-Tamirat ◽  
Joel Guidez ◽  
Antoine Gerschenfeld ◽  
Konstantin Mikityuk ◽  
...  
Keyword(s):  
Vessel Wall ◽  
Cooling System ◽  
Heat Removal ◽  
Strong Line ◽  
Cooling Systems ◽  
Decay Heat ◽  
Cooling Loops ◽  
Heat Removal System ◽  
Removal System ◽  
Residual Heat

Abstract The Decay Heat Removal System (DHRS) for the ESFR Concept consists of three cooling systems, which provide highly reliable, redundant and diversified decay heat removal function. Two of the systems provide strong line of defense, whereas the third system provides a weak line of defense. This third DHR system, DHRS-3, involves separate oil and water cooling loops integrated in the reactor pit, which is installed instead of the safety vessel. It is hoped that the proposed DHR concept enables a robust demonstration of the practical elimination. For its confirmation, detailed numerical analysis is needed as a basis for further investigation. Supporting this approach, the current CFD computation provides a preliminary thermal analysis of the capability of the oil cooling system in the reactor to be used for residual heat removal pit in case of an emergency. For the evaluation, different heat flux values are assumed at the vessel wall to examine the range of the resulting temperatures. The temperature of the main vessel wall should remain below 800°C. Furthermore, a sodium leakage at 500°C into the reactor pit is assumed. The concrete structure should remain below 70°C.

Sign in / Sign up

Export Citation Format

Share Document