A separate effect test on the cooling behavior in a pressurized water reactor core under a low reflooding rate condition by using ATLAS and RELAP5/MOD3.3 code assessment

► A separate effect test was performed for the core quench behavior in a PWR core. ► A low reflooding rate test was performed for APR1400 by using the ATLAS. ► A DVI, a reverse heat transfer from SGs and the steam binding effect was simulated. ► The test data were used to assess the reflood models of the RELAP5/MOD3. ► The modified version of RELAP5/MOD3.3 showed better agreement with the test data.