Share device of Shanghai Jiao Tong University (SJTU)

4.1 HYMIT (a Mid-scale Hydrogen Behavior Test Facility)

HYMIT is a midsize Hydrogen Mitigation Test facility. The main part is the steel cylinder tank which is 4 meters high and 2 meters in diameter. The tank volume is about 12 m3. It is designated to test the hydrogen recombination and combustion behavior. The mixed gas content, gas temperature and pressure and speed of flame can be measured with gas analyzer, thermocouple array, piezoelectric pressure sensors and photodiode array. The facility is designed to test the characteristics of current available ignitor and passive autocatalytic recombiners (PAR) as well as new hydrogen mitigation technologies. It can deal with hydrogen concentrations between 0 and 30 vol.% , as well as steam concentrations between 0 and 50 vol %.

4.2 WAFT (Water Film Test)

The Water Film Test (WAFT) facility is dedicated to study Passive Containment Cooling system (PCCS) of GEN-III plants. WAFT consists of a stainless plate (5m long, 1.2m wide) mounted on a metallic frame allowing for plate inclination. The surface of the plate undergoes a preparation by painting with organic zinc to maintain designated wettability. The plate flat is heated by heating oil, and the power can reach 100 kW/m2. A parallel plate with visualization windows, about 30 cm apart from the test plate, constitutes a part ofa rectangular channel whichenables the simulationof the air gap between the containment steel envelope and the metallic baffles in the reference passive reactor design. A blower at the bottom of the channel simulates the natural circulation air flow occurring in the reference plant conditions. Variation of the reference air velocity approximately from 0 to 12 m/s is allowed. The water film distribution box is mounted on the top of the facility to ensure the uniform water film distribution of the inlet. The water film and air temperature, and water film thickness are measured with thermocouples; air flow velocity and surface wave velocity are measured with optical sensor, hot-wire anemometer and high-speed camera;and heat fluxes are measured withheat flux sensors (please give the measurement point densities of temperature and heat flux).

4.3 REPEC-II (Full-height ERVC Facility)

REPEC is a series of test facilities in Shanghai Jiao Tong University (SJTU) studying external reactor vessel cooling (ERVC) related thermos-hydraulic phenomena under in-vessel retention (IVR) strategy for severe accident mitigation. REPEC-II, the recent version facility of REPEC, has been erected in the year of 2012, which has been successfully applied for investigation and understanding on ERVC flow boiling characteristics, natural circulation(NC) ability in the channel between reactor pressure vessel (RPV) and the thermal insulation, as well as corresponding experimental techniques. It is of full-height, and has been constructed based on the data, features and experience acquired from its pilot facility, REPEC-I. The main object of REPEC-II is to study in detail feasibility of IVR-ERVC strategy and its behavior for large-scale advanced reactors. REPEC-II facility is functionally designed and expected to investigate limits of external cooling, ie. CHF distribution on RPV wall under various non-uniform heating conditions, flow characteristics within ERVC natural circulation (including flow instabilities), influences of real plant and severe accident conditions on ERVC abilities (e.g. considering such factors as heating material identical with real RPV, various aging surface conditions, chemistry of cooling water, dynamic load on thermal insulation, etc.), along with possible, practical enhanced heat removal approaches.
Basic Information of REPEC-II facility:
·         Height of the facility: 11568 mm (available for full-height test);
·         Ratio of important NC flow area: 1:100 (model/prototype)
·         Heating capacity of test section: up to 1.2MW;
·         Heat flux attained in the past test: up to 2.2-2.6MW/m2;
·         Heat surface materials: copper; RPV material (eg. SA508-III steel); aged surface
·         Heating capacity of auxiliary heater: 75kW;
·         Working fluids: Deionized water, Tap water, BA solution, TSP solution, BA+TSP solution (please give the full name of the working fluids in term of BA and TSP).