As part of a series of impact tests, the Federal Railroad Administration (FRA) sponsored a research team from Transportation Technology Center, working with Volpe National Transportation Systems Center (Volpe), to analyze the side impact puncture performance of a surrogate DOT-113 tank car filled with cryogenic liquid nitrogen (LN2). This was the third test in a planned series of four tests on DOT-113 tank cars and surrogates. Researchers performed pre-test analyses of the DOT-113 surrogate filled with LN2 (Test 12), and the research team conducted the impact test on July 24, 2021. The surrogate tank car was impacted by a 297,200-lb ram car fitted with a 12 x 12-inch impactor traveling at 18.3 mph. The impact resulted in a significant amount of deformation but did not puncture the tank car. After the test, the team updated the pre-test finite element (FE) model to represent the measured speed of the ram car but observed some discrepancies between the test measurements and simulation results. The testing and modeling effort is described in detail in a separate FRA Technical Report; this report is focused on a phase change discrepancy noted during Test 12.