Main Basic information of the centre Certification rus/eng
Â-213

       The VITRA test facility is a thermo-hydraulic test facility designed for investigation of the transfer of the debris of different types and sizes, generated during loss of coolant accident within NPP containment.
       The thermo-hydraulic configuration of the test facility allows creating and maintaining flow with flat velocity profile in the open channel of 0,5 õ 0,5 meters within the velocity range of 0,01 to 0,5 m/sec at constant temperature of 30–35°Ñ.
       The test facility consists of a core simulator, a pump, a module for water injection into the channel and flow rate measurement, filtering module, temperature stabilization circuit and pump load controller.
       The core simulator is an open channel of rectangular cross-section, with the following dimensions: width – 0.513 m, height 0,8 m, and length - 3,5 m. Maximal pumping capacity provides for the average water flow rate of 0,5 m/sec in the 0,5 õ 0,5 m channel.
       The module for water injection into the channel and flow rate measurement consists of:
  • distribution pressure header;
  • four pipelines of different diameters with isolation valves, regulating valve and measurement diaphragm;
  • channel inlet pipe.

       The filtering module protects the pump against the particles exceeding 0,2 mm in size.
       The test facility is equipped with instrumentation, including detectors of the water level in the channel, flow rate in the test facility circuit, flow rate in the channel and temperature. The flow rate of the patterns (debris) is measured with the aid of optical video-system by means of recording and subsequent computer processing of the images.

Purpose of the VITRA test facility

  • investigation of the processes of deposition and transfer with water flow of the debris (heat insulation, paint, concrete and iron oxides) generated during LOCA in the containment.
  • investigation of the process of pressure decrease due to clogging of filters by debris.


Channel dimensions — 0,513 õ 0,8 õ 3,5 m
Maximal water velocity in the channel — 0,5 m/sec
Minimal water velocity in the channel — 0,011 m/sec
Maximal flow rate in the channel — 450 m3/hour
Minimal flow rate in the channel — 10 m3/hour
Water temperature in the channel — 30–35°Ñ
   1 – core simulator; 2 – level meter; 3 – debris loading point; 4 – meshwork; 5 – pump; 6 – regulating valve; 7 – filters;
   8 – flow meter; 9 – isolation valve; 10 – heat exchanger


Results

       In 2002–2003, an experimental program was conducted under a contract with IRSN (France) to investigate the processes of transfer and deposition of the debris and decrease of pressure in relation to the French PWR reactors.

Prospects

       Increased concern in the outstanding problem of filters loading in NPP pit pumps in accidents with leaks that was confirmed during the International meeting of experts in Albuquaque (USA, February 2004), provides with objective basis for performance of research activity in this field including the use of the VITRA test facility. In addition the test facility capacity ensures to perform the tests on validation of the designed CFD codes.