MINIPANDA - A Small Scale Containment Test Facility with Novel Instrumentation Is Used for Code Validation for an Air Ingress Scenario

Abstract

MiniPanda, a small-scale containment test facility built at ETH Zürich, was equipped with novel field measurement techniques. The capabilities of the facility were demonstrated in a first test series on an air ingress scenario. The ingress of air into a helium cooled reactor is considered to be one of the most severe accidents for the GenIV-type helium cooled reactor. The air once arrived inside the reactor can cause the oxidation of the graphite structures.The ingress of air into a helium environment was investigated experimentally and analytically using the commercial CFX-13 and StarCCM+ 5.06 CFD codes. The experimental volume consists of two cylindrical vessels that are filled separately with air or helium. The experiment is initiated by removing the blockage from the pipe connecting the two vessels. The experimental and analytical results of the consequent buoyancy-driven air ingress are compared against each other.