Study On The Intensification And Application Of The Heat Transfer Process In Stirred Tanks With Gas-liquid Phases

Energetic matrials are playing a fundamental role in national defense and economic construction. As the energy source of weapon system, its performance decides the safety and damage efficiency. Energetic compounds are basic components of energetic materials. Producing energetic compounds with high energy, stability good and long service life is one of the foreland fields in the present energetic materials research. In this thesis, the intensification of the heat transfer process in stirred tanks was studied in order to solve problems in the synthetic processes of the energetic compounds, which contains strong exothermic reactions. Firstly, the experiments were conducted in a stirred tank with helical coil on different airflow rate. Convective heat transfer coefficients of the outer coil surface were obtained. Secondly, the heat transfer process in stirred tanks with differnet constructive parameters of coils was simulated by CFD software. The coil design suggestions were put forward. Finally, the nitration tank reactor (430 L) and the hydrolysis tank reactor (900 L) were designed. The main contents are as follows:1. The products of some strong exothermic reactions contain gas. Experiments in a stirred tank with coil of five different air flowrate were conducted. The temperature of the stirred tank and coil were measured to calculate the convective heat transfer coefficients. These data could be taken as the reference to design some special strong exothermic reactors.2. Coil is the key part of heat transfer process in strong exothermic stirred tanks. The structure models of coils with different front diameters and screw pitches were built by GAMBIT. The heat transfer process in stirred tanks with simulated by FLUENT. The velocity fields, temperature fields and heat transfer coefficients were obtained. These data could help us to put forward coil design suggestions.3. According to the research results of heat transfer experiments and computer simulation. The 430 L nitration stirred tank used in a synthetic process of energetic compounds was designed, simulated and optimized. The nitration stirred tank performed well in the pilot experiment4. The 900 L hydrolysis stirred tank used in a synthetic process of energetic compounds was designed. This reactor performed well in the pilot experiment.