Study on combustion and flame retardant mechanism of combustible working fluid ammonia

The current environmental problems are becoming increasingly prominent, and the natural refrigerant ammonia as an environmentally friendly refrigerant has once again attracted widespread attention in the scientific community. However, NH3 has the problem of flammability and explosion, and there are certain safety hazards in practical applications. In this paper, we adopt the quantum chemical density generalized theory calculation method to investigate the combustion and flame-retardant mechanism of NH3 at the calculation level of M06-2X/6-311+G(d, p), and obtain the microscopic reaction path of the reaction process. It is shown that NH3 can react with H, O and OH radicals in three ways: firstly, it undergoes its own cleavage reaction to produce H radicals; secondly, it collides with oxygen to produce OOH radicals; thirdly, it collides with reactive radicals to produce new reactive radicals, and NH3 can react with H, O and OH radicals, and the reaction has a low energy barrier. In addition, the microscopic flame retardant paths of two typical flame retardant groups, F and CF3, to the combustible molecule NH3 were calculated to verify their flame retardant effects. In this paper, the combustion and flame retardant mechanism of the combustible work material ammonia is investigated from the microscopic molecular perspective, which provides a reference for the combustion and flame retardant mechanism of the new generation of low greenhouse effect work materials. © 2021, Editorial Board of CIESC Journal. All right reserved.