Experimental study of explosion characteristics caused by High-Temperature sodium leakage from a heat pipe into air

Abstract

Heat pipe cooled reactor is an advanced reactor design that uses an array of in-core heat pipes for passive heat transfer.In heat pipe leakage accident, combustion or even explosions produced by high-temperature sodium reacting with the air can cause core damage. In this paper, the explosion characteristics of the sodium leakage are studied by analyzing the physical phenomena and studying the pressure pulse and the temperature rise. Based on the explosion phenomena, this paper proposes a phenomenological model for sodium heat pipe leakages. A small explosion, accompanied by yellow light, occurred at the instant of the sodium heat pipe leakage. The overpressure observed, increased with an increase in the initial temperature and also with the break size. The results of this paper include experimental phenomena and quantitative analysis of explosion, which provide a basis for the development of subsequent mechanistic model and safety evaluation of the heat pipe cooled reactor.