Comparison of Heat Transport Capability of a Steam Generator (SG) in a High-Temperature Gas-Cooled Reactor with That of an SG in Other Types of Reactors

1987 ◽  
Vol 78 (3) ◽  
pp. 216-226
Author(s):  
Takao Hayashi
Keyword(s):  
High Temperature ◽  
Heat Transport ◽  
Steam Generator ◽  
Heat Transport Capability ◽  
High Temperature Gas

The Water Ingress Mass Analysis on Steam Generator Heat-Exchange Tube Rupture Accident of High Temperature Gas-Cooled Reactor

2009 ◽  
Author(s):  
Yan Wang ◽  
Yanhua Zheng ◽  
Fu Li ◽  
Lei Shi ◽  
Zhiwei Zhou
Keyword(s):  
High Temperature ◽  
Heat Exchange ◽  
Steam Generator ◽  
Mechanical Load ◽  
Radioactive Isotopes ◽  
Primary Circuit ◽  
Secondary Circuit ◽  
Water Ingress ◽  
Heat Exchange Tube ◽  
High Temperature Gas

The module high temperature gas-cooled reactor (HTGR) is an advanced reactor with high safety level. The steam generator heat-exchange tube rupture (SGTR) accident (or water ingress accident) is an important and particular accident which will result in water ingress to the primary circuit of reactor. Water ingress may, in turn, result in chemical reaction of graphite fuel and structure with water, causing release of radioactive isotopes and generation of explosive gaseous in large quantity. The analysis of SGTR is significant for verifying the inherent safety characteristics of HTGR. One of the key factors is to estimate the amount of water ingress mass which is used to evaluate the severity of the accident consequence. The 200MWe high temperature gas-cooled reactor, which is designed by the Institute of Nuclear and New Energy Technology of Tsinghua University, is selected as an example to analyze. The accident scenarios of double-ended rupture of both single and two heat-exchange tubes at the inlet and outlet of steam generator are simulated respectively by RETRAN-02. The results show that the amount of water ingress mass is related to the break location, the number of ruptured tubes (or the break size). The greater the number of ruptured tubes or the break size, the larger the amount of water ingress mass. It is important to design the draining pipe line with reasonable diameter, which should be optimized based on economy and safety considerations for preventing large water ingress to the reactor primary circuit, restricting the change rate of mechanical load on SG, and reducing the radioactive isotopes release to the secondary circuit.

Simulation of a Once-Through, Helical-Coiled Steam Generator of High Temperature Gas-Cooled Reactor

2009 ◽  
Author(s):  
Jinliang Ye ◽  
Yangping Zhou ◽  
Xiaoming Chen ◽  
Yuanle Ma ◽  
Fu Li ◽  
...  
Keyword(s):  
High Temperature ◽  
Steam Generator ◽  
Static Model ◽  
Mass Energy ◽  
Design Data ◽  
The Difference ◽  
Steady State Simulation ◽  
Energy And Momentum ◽  
Blast Program ◽  
High Temperature Gas

A quasi-static model of a helical coiled Once-Through Steam Generator of High Temperature gas-cooled Reactor-Pebble Bed Module (HTR-PM) is developed based on the fundamental conservation of fluid mass, energy and momentum. The steam generator is handled with single tube concept and is divided into three regions as subcooled region, boiling region and superheated region. The equations are solved by Rung-Kutta method. The steady-state simulation results agree well with the design data. Furthermore, the results are compared with the results gotten from THERMIX/BLAST program, and the difference between them is small which shows the model and the methodology are reasonable.

Modeling of the Supercritical Steam Generator of MHTGR in Engineering Simulator

2014 ◽  
Author(s):  
Dan Liu ◽  
Jun Sun ◽  
Zhe Sui ◽  
Chun-lin Wei ◽  
Yu-liang Sun
Keyword(s):  
Heat Transfer ◽  
High Temperature ◽  
Steam Generator ◽  
Supercritical Water ◽  
Heat Transfer Characteristics ◽  
Coupling Effects ◽  
Transfer Characteristics ◽  
Helical Tubes ◽  
Steam Generator Model ◽  
High Temperature Gas

The Modular High Temperature Gas-cooled Reactor (MHTGR) could realize higher efficiency and lower costs by developing the multi-modular high temperature gas-cooled reactors combined with supercritical steam turbine unit. The coupling effects among different modules are crucial to the designs and operation analyses of the multi-modular reactors. By establishing the engineering simulator for multi-modular reactors, the coupling effects can be studied and optimized to advance the reactor designs, due to the advantages of real-time calculations and coupled calculations. As key energy transfer equipment, the steam generator is very important to the reactor operation, and focused in the modeling of the engineering simulator system for multi-modular reactors. In this paper, the once-through steam generator consisted of helical coils was modeled and optimized in the vPower integrated simulation platform. From the detailed analyses of the distributions of temperatures, heat flux, and other parameters along the heat transfer tubes, it showed that the steam generator model well presented the supercritical water properties and heat transfer characteristics inside helical tubes. Also, the heat transfer correlations of the supercritical water inside helical tubes were investigated, discussed and also compared to test the uncertainty and influence to the whole steam generator model. And the results indicated that most heat transfer correlations showed similar results and had little effect on the primary side in the steady state operation condition. In future work, the model and heat transfer characteristics of the supercritical steam generator will be further tested in more transients and integrated into complete engineering simulator for multi-module reactors.

scholarly journals Procedure of Active Residual Heat Removal after Emergency Shutdown of High-Temperature-Gas-Cooled Reactor

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Xingtuan Yang ◽  
Yanfei Sun ◽  
Huaiming Ju ◽  
Shengyao Jiang
Keyword(s):  
High Temperature ◽  
Heat Shock ◽  
Steam Generator ◽  
Flow Rate ◽  
Heat Removal ◽  
Emergency Shutdown ◽  
Start Up ◽  
Sudden Load ◽  
High Temperature Gas ◽  
Residual Heat

After emergency shutdown of high-temperature-gas-cooled reactor, the residual heat of the reactor core should be removed. As the natural circulation process spends too long period of time to be utilized, an active residual heat removal procedure is needed, which makes use of steam generator and start-up loop. During this procedure, the structure of steam generator may suffer cold/heat shock because of the sudden load of coolant or hot helium at the first few minutes. Transient analysis was carried out based on a one-dimensional mathematical model for steam generator and steam pipe of start-up loop to achieve safety and reliability. The results show that steam generator should be discharged and precooled; otherwise, boiling will arise and introduce a cold shock to the boiling tubes and tube sheet when coolant began to circulate prior to the helium. Additionally, in avoiding heat shock caused by the sudden load of helium, the helium circulation should be restricted to start with an extreme low flow rate; meanwhile, the coolant of steam generator (water) should have flow rate as large as possible. Finally, a four-step procedure with precooling process of steam generator was recommended; sensitive study for the main parameters was conducted.

A Numerical Analysis on Graphite Dust Deposition and Resuspension in HTR-10 Steam Generator

2014 ◽  
Author(s):  
Wei Peng ◽  
Tian-qi Zhang ◽  
Ya-nan Zhen ◽  
Su-yuan Yu
Keyword(s):  
High Temperature ◽  
Steam Generator ◽  
Load Capacity ◽  
Fission Products ◽  
Dust Deposition ◽  
Preliminary Calculation ◽  
Transfer Tube ◽  
High Load Capacity ◽  
Fuel Elements ◽  
High Temperature Gas

The behavior of graphite dust is important to the safety analysis of High-Temperature Gas-cooled Reactor (HTGR). The fission products released by fuel elements would enter the primary loop and combine with dust, resulting in that the dust has a high load capacity of cesium, strontium, iodine and tritium. It would bring difficulty and inconvenience to the maintenance and repair of steam generator. Therefore, the behavior of graphite dust in the steam generator is essential to the safety of High Temperature Gas-cooled Reactors. The present study focused on the deposition and resuspension of graphite dust in steam generator of HTR by numerical method. The results show that the graphite dust in steam generator deposits on the surface of heat transfer tube through turbulent deposition, thermophoretic deposition, and other depositional mechanisms, of which thermophoretic deposition is the main mechanism for the particles with the diameter of 2.2μm in the present study. The preliminary calculation result shows that about 6760mg/m2 of graphite dust tends to load on the tube surface.

Sign in / Sign up

Export Citation Format

Share Document