Scaling of Passive Condenser System Separate Effect Facility

2008 ◽  
Author(s):  
Shripad T. Revankar ◽  
Seungmin Oh ◽  
Wenzhong Zhou ◽  
Gavin Henderson
Keyword(s):  
Cooling System ◽  
Forced Flow ◽  
Test Facility ◽  
Prototype System ◽  
Scaling Analysis ◽  
Reactor Accident ◽  
Cooling Period ◽  
Separate Effect ◽  
Suppression Pool

The Passive Containment Cooling System (PCCS) of the Simplified Boiling Water Reactor (SBWR) is a passive condenser system designed to remove energy from the containment for long term cooling period after a postulated reactor accident. Depending on pressure condition and noncondensable (NC) gas fraction in drywell (DW) and suppression pool (SP), three different modes are possible in the PCCS operation namely the forced flow, cyclic venting and complete condensation modes. The prototype SBWR has total of six condenser units with each units consist of hundreds of condenser tubes. Simulation of such prototype system is very expensive and complex Hence a scaling analysis is used in designing an experimental model for the prototype PCCS condenser system. The motive for scaling is to achieve a homologous relationship between an experiment and the prototype which it represents. A scaling method for separate effect test facility is first presented. The design of the scaled test facility for PCCS condenser is then given. Data from the test facility are presented and scaling approach to relate the scaled test facility data to prototype is discussed.

Scaling Analysis of Mixing and Thermal Stratification in Passive Containment

2013 ◽  
Author(s):  
Junchi Cai ◽  
Shengfei Wang ◽  
Fenglei Niu ◽  
Pengyu Shi ◽  
Xin Liu ◽  
...  
Keyword(s):  
Thermal Stratification ◽  
Cooling System ◽  
Mixing Time ◽  
Develop Model ◽  
Prototype System ◽  
Scaling Analysis ◽  
Reactor Accident ◽  
Cooling Period ◽  
Geometric Scaling

The passive containment cooling system (PCCS) is one of typical passive systems of AP1000, which is a passive condenser system, designed to remove energy from the containment for long term cooling period after a postulated reactor accident, like LOCA or MSLB. One of the key phenomena of PCCS is mixing and thermal stratification inside the containment. In order to establish empirical correlations and develop model of this phenomenon, the experimental study is essential. Because it is difficult to use prototype system for research, so a scaling analysis is needed to design an experimental facility with smaller scale and accelerated time to simulate the prototype system. In this paper, a scaling method for mixing and thermal stratification is given and gets the governing equations and scaling criterions. In final, a group of primary parameters of the experiment, such as mixing time and volume rate of flow, is given in the form of geometric scaling ratio which is chosen by the designer.

Experimental Study of Effects of Non-Condensable on Condensation in a Vertical Tube Bundle

2009 ◽  
Author(s):  
Wenzhong Zhou ◽  
Gavin Henderson ◽  
Shripad T. Revankar
Keyword(s):  
Heat Transfer ◽  
Cooling System ◽  
Tube Bundle ◽  
Condensation Heat Transfer ◽  
Forced Flow ◽  
Test Facility ◽  
Flow Mode ◽  
Scaling Analysis ◽  
Condenser Tube ◽  
Air Concentration

One of the engineered safety systems in the advanced boiling water reactor is a passive containment cooling system (PCCS) which is composed of a number of vertical heat exchanger. After a loss of coolant accident, the pressurized steam discharged from the reactor and the noncondensable (NC) gases mixture flows into the PCCS condenser tube. The PCCS condenser must be able to remove sufficient energy from the reactor containment to prevent containment from exceeding its design pressure. The efficient performance of the PCCS condenser is thus vital to the safety of the reactor. In PCCS condenser tube three flow conditions are expected namely the forced flow, cyclic venting and complete condensation modes. The PCCS test facility consists of steam generator (SG), instrumented condenser with secondary pool boiling section, condensation tank, suppression pool, storage tank, air supply line, and associated piping and instrumentation. The specific design of condensing tube is based on scaling analysis from the PCCS design of ESBWR. The scaled PCCS is made of four tubes of diameter 52.5mm and height 1.8 m arranged in square pitch. Steam air mixture condensation tests were carried out in a through flow mode of operation where the mixture flows through the condenser tube with some steam condensation. Data on condensation heat transfer were obtained for two nominal pressures, 225 kPa and 275 kPa and for air concentration fraction from 0 to 13%. Test results showed that with increase in pressure the condensation heat transfer increased. The presence of the air in the steam decreased the condensation heat transfer coefficient from 10 to 45% depending on air fraction in the steam.

Evaluation of the Scaling Analysis Model of the EU-APR1400 Core Catcher Cooling System Test Facility

2014 ◽  
Author(s):  
Bo W. Rhee ◽  
K. S. Ha ◽  
R. J. Park ◽  
J. H. Song
Keyword(s):  
Performance Test ◽  
Cooling System ◽  
Reactor Core ◽  
Test Facility ◽  
Scaling Analysis ◽  
Analysis Model ◽  
System Pressure ◽  
Test Loop ◽  
Core Catcher ◽  
The Eu

This paper describes the basic design features of the EU-APR1400 reactor core catcher cooling system and its test facility, and the associated scaling analysis model. An assessment of the validity of the scaling analysis using the preliminary performance test result of the test facility is described. This includes comparison of the predicted mass flow rate of the test loop as a function of the heat load to the facility, inlet flow subcooling and system pressure to the experimental results.

Three Cooling Seasons Monitoring of Exergetic Performance Analysis of an EAHE Assisted Solar Greenhouse Building

2012 ◽  
Vol 135 (2) ◽  
Author(s):  
Onder Ozgener ◽  
Leyla Ozgener
Keyword(s):  
Heat Exchanger ◽  
Closed Loop ◽  
System Analysis ◽  
Cooling System ◽  
Experimental System ◽  
Cooling Mode ◽  
Cooling Period ◽  
Solar Greenhouse ◽  
And Performance

The present manuscript experimentally investigated the exergetic performance (efficiency) of a closed loop earth to air heat exchanger (underground air tunnel) in the cooling mode. The experimental system was commissioned in June 2009 and experimental data collecting have been conducted since then. The data, consisting of hourly thermodynamics records a year cooling period, 2009–2011, were measured in the Solar Energy Institute of the Bornova Campus at Ege University. At the present time, the database contains more than 40,000 records of measurements. Exergetic efficiencies value of the system and system components have been analyzed. Furthermore, a long term exergetic modeling of a closed loop earth-to-air heat exchanger solar greenhouse cooling system for system analysis and performance assessment is presented. Exergetic efficiency of the system and its compenents at various reference states are also determined.

Design of 1/4 Scale Performance Test Facility for the PMR200 RCCS

2014 ◽  
Author(s):  
Y. Y. Bae ◽  
B. H. Cho ◽  
J. H. Kim ◽  
M. H. Kim ◽  
Y. W. Kim
Keyword(s):  
Performance Test ◽  
Cooling System ◽  
Test Facility ◽  
Maximum Temperature ◽  
Scaling Analysis ◽  
Reactor Safety ◽  
Key Technologies ◽  
Scale Test ◽  
Demonstration Plant ◽  
Cavity Cooling

One of the key technologies for the development of the PMR200, a VHTR demonstration plant, is a verification of the reactor cavity cooling system (RCCS) performance, which ensures reactor safety by passively removing heat from the reactor cavity. A preliminary numerical analysis of the RCCS showed that the maximum temperature in RCCS reached up to 700°C. Since radiation dominates the heat transfer at such a high temperature, it should be considered in both the design and associated numerical works for the test facility. For a verification of the RCCS performance, a 1/4 scale test facility has been constructed, and a performance test is being carried out. As the first step for the design of the test facility, a scaling analysis has been performed; and the ratio of variables between the model and prototype were determined. Numerical calculations using a CFD code were also performed to support the scaling analysis. It was confirmed that the scaling analysis was reasonably correct.

Vertical Tube Passive Condenser Under Secondary Pool Water Level Transient

2010 ◽  
Author(s):  
Shripad T. Revankar ◽  
Wenzhong Zhou
Keyword(s):  
Water Level ◽  
Cooling System ◽  
Vertical Tube ◽  
Test Facility ◽  
Flow Mode ◽  
Scaling Analysis ◽  
Water Level Change ◽  
Level Change ◽  
Pool Water ◽  
System Pressure

An experimental work was carried out on a passive containment cooling system (PCCS) test facility where the effect of PCCS pool water level change on the PCCS heat transfer characteristics was investigated. The specific design of condensing tube was based on scaling analysis from the PCCS design of Economic Simplified Boiling Water Reactor (ESBWR). The annulus between the primary condensing tube and the secondary boiling tube is filled with water and serves as water pool. During the test, steam generated in the pool is discharged through three steam exit nozzles located symmetrically at the top of the secondary boiling tube. Transient tests carried out with secondary pool water level change show that the system pressure for complete condensation mode increases with decrease in water level, however rate of condensation is almost constant. However, if the PCCS is operated in through flow mode the system pressure (primary side pressure) is constant, however, the condensate rate decreases indicating that some of the steam does not condense.

Containment Sump Active Strainers

2005 ◽  
Author(s):  
A. R. Mehta ◽  
A. J. Bilanin ◽  
J. Hamel ◽  
A. Kaufman
Keyword(s):  
Nuclear Power ◽  
Cooling System ◽  
Safety Issue ◽  
Water Source ◽  
Nuclear Regulatory Commission ◽  
Test Facility ◽  
Plant Design ◽  
Test Environment ◽  
Pressurized Water

The containment sump, also known as emergency or recirculation sump, is part of the Emergency Core Cooling System (ECCS). Every nuclear power plant is required by regulations to have an ECCS to mitigate a design basis accident. The containment sump of a Pressurized Water Reactor (PWR) collects reactor coolant and chemically reactive spray solutions following a Loss of Coolant Accident (LOCA). The containment sump serves as the water source to support long-term recirculation. This water source, the related pump inlets and the piping between the source and inlets are all important safety components. Suppression pools in Boiling Water Reactors (BWRs) serve the same purpose as PWR containment sumps. Historically, a passive debris screen has been used to prevent debris from entering the ECCS suction lines surrounding the containment sump. Previous incidents demonstrated that the potential for excessive head loss across the containment sump screens exists because of the accumulation of debris on the containment sump. Because of this, the US Nuclear Regulatory Commission (NRC) has concluded that containment sump blockage is a potential concern for PWRs. US BWRs were required to conduct plant-specific evaluations of their suction strainer performance and, as required, modify their plant design. While all US PWRs are required to resolve this Generic Safety Issue (GSI-191), containment sump blockage continues to be a major concern for both BWRs and PWRs internationally. This paper describes the GE Active Strainer design, one of several strainers developed to resolve this generic safety issue. The Active Strainer presents an innovative and novel method of addressing containment sump blockage. This strainer employs a rotating, or “active”, plow and brush that sweep over a perforated surface. By keeping the perforated surface free of debris, fluid is allowed to pass through, providing sufficient coolant to the ECCS pumps to support long-term recirculation. Due to the unique method by which the Active Strainer filters coolant, a test program was developed to demonstrate its functionality and viability. Intrinsic differences between passive and active solutions make previous methods of testing obsolete for the GE Active Strainer. Moreover, the complex and varying geometries and conditions of actual plant containment sumps are difficult to replicate. Therefore, a methodology was developed to ensure prototypical test environment and strainer debris loads in a scaled test facility. This paper will discuss the GE Active Strainer design, the testing conducted and subsequent conclusions.

Post Small-Break LOCA Long Term Core Cooling Performance in ACME Test Facility

2016 ◽  
Author(s):  
Zhanfei Qi ◽  
Sheng Zhu
Keyword(s):  
Nuclear Power ◽  
Cooling System ◽  
Safety Margin ◽  
Test Facility ◽  
Passive Safety ◽  
Pressurized Water Reactor ◽  
Pressurized Water ◽  
Safety Features ◽  
Core Cooling

CAP1400 Pressurized Water Reactor is developed by China’s State Nuclear Power Technology Corporation (SNPTC) based on the passive safety concept and advanced system design. The Advanced Core-cooling Mechanism Experiment (ACME) integral effect test facility, which was constructed at Tsinghua University, represents a 1/3-scale height of CAP1400 RCS and passive safety features. It is designed to simulate the performance of CAP1400 passive core cooling system in the small break loss of coolant accidents (SBLOCA) for design certification, safety review and safety analysis code development. The Long Term Core Cooling (LTCC) post-LOCA could be simulated by ACME as well. A series of test cases with various break sizes and locations with post-LOCA LTCC period were conducted in ACME facility. This paper describes the post-LOCA LTCC test conducted in ACME test facility. The LTCC phenomena in different cases are very similar. It’s found that the interval that switching from IRWST injection to sump recirculation has the least safety margin. However, it’s shown that the post-LOCA LTCC in ACME could be well maintained by passive core cooling system according to the test results even though the recirculation water level in ACME IRWST-2 is lower than the containment recircualtion level in CAP1400 conservatively.

ACME Upper Plenum Entrainment Phenomena Scaling Analysis and Criteria

2012 ◽  
Author(s):  
Zishen Ye ◽  
Yuquan Li ◽  
Han Wang ◽  
Lian Chen ◽  
Wei Li
Keyword(s):  
Cooling System ◽  
Surface Region ◽  
Test Facility ◽  
Scaling Analysis ◽  
Analysis Method ◽  
Hydraulic Facility ◽  
Near Surface ◽  
The Core ◽  
Cooling Mechanism ◽  
Core Cooling

ACME (Advanced Core-cooling Mechanism Experiment) is an integral thermal-hydraulic facility designed to produce data for validating the software that is intended to be used to calculate the behavior of large advanced PWRs in China. Design of ACME is working on now. ACME would simulate the important phenomenon of the reactor cooling system and passive core cooling system of PWR. When the level is lower than the hot leg nozzles, droplets would be carried out by the vapor. This phenomenon is entrainment of upper plenum. Entrainment is a important phenomena in the upper plenum both of prototype and test facility. It would influence the level and inventory of the core. We analyzed entrainment phenomena in the upper plenum through H2TS scaling analysis method [1] based on Ishii’s pool entrainment model [2] in this paper. H2TS scaling analysis method includes two parts: one is the top-down system scaling and the other is the bottom-up process scaling analysis. Ishii’s pool entrainment model define the entrainment as the ratio of the droplet to vapor mass flux and divide three regions by the diameter and velocity of the droplet, including near surface region, momentum controlled region and deposition controlled region. The key scaling criteria and scaling ratios which should be met under ACME design are given for different entrainment regions. Based on these criteria and ratios, ideal upper plenum design of ACME facility will simulate the entrainment phenomena conservatively.

An electric propulsion long term test facility

1979 ◽  
Author(s):  
G. TRUMP ◽  
E. JAMES ◽  
R. VETRONE ◽  
R. BECHTEL
Keyword(s):  
Electric Propulsion ◽  
Test Facility
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