PWR PACTEL facility

The PWR PACTEL test facility is designed and constructed to be utilized in the safety studies related to EPR type pressurized water reactor thermal hydraulics. A significant design and construction basis for the PWR PACTEL facility is the utilization of some parts of the original PACTEL facility constructed at year 1990. The original PACTEL facility is used to simulate the thermal hydraulic behavior of the Soviet-designed VVER-440 pressurized water reactors currently in use in Finland. The PWR PACTEL facility consists of a reactor vessel model, two loops with vertical steam generators, a pressurizer, and Emergency Core Cooling Systems (ECCSs). The pressure vessel model is comprised of a U-tube construction modeling the downcomer, lower plenum, core, and upper plenum. The core is simulated by a 1 MW electric heater rod assembly which consists of 144 heater rods. The four loops of the reference PWR are lumped into two model loops. The possibility to use the original PACTEL facility for future needs is maintained.

Completely new construction of loops and steam generators is introduced to the PWR PACTEL facility. The two primary loops with vertical steam generators are fully representative for PWR applications. Each loop has a steam generator of 51 full size inverted U-tubes with five different tube heights, a hot leg, and a cold leg. The instrumentation of the loops and especially of the primary side U-tubes is considerably extensive. All together about 250 temperature, pressure, and differential pressure measurement transducers are attached to allow deeper analysis of steam generator behavior. In one of the steam generators, six U-tubes are instrumented with bottom-to-top differential pressure measurements for both up flow and down flow sides of the tube.

The specific focus of the PWR PACTEL studies is to gain experience on thermal hydraulic behavior of the EPR type pressurized water reactor and related accident management procedures. The focus is set on vertical steam generator construction and operation, in particular. The experimental data base of the PWR PACTEL experiments will contribute to validation processes of several computer codes. Education of experts on EPR specific issues and preservation of know-how on experimental research are the two major tasks of the PWR PACTEL project.

Reference power plant	PWR (EPR)
Volumetric scale	1:405 (pressure vessel) 1:400 (steam generators) 1:562 (pressurizer)
Height scale	1:1 (pressure vessel) 1:4 (steam generators) 1:1.6 (pressurizer)
Maximum heating power	1 MW
Maximum primary / secondary pressure	8.0 MPa / 4.65 MPa
Maximum primary /secondary temperature	300 °C / 260 °C
Maximum cladding temperature	800 °C
Number of loops	2
Steam generator tube diameter	Ø19.05 x 1.24 mm
Average steam generator tube length	6.5 m
Number of U-tubes in one steam generator	51
Number of instrumented U-tubes	SG1 8 SG2 14 (51)
Main material of components	stainless steel AISI 304
Insulation material	mineral wool, aluminum cover plate