• The Euler-Eulerian and Euler-Lagrangian two-fluid model were used to study the hydrodynamic behavior of DTB crystallizer.
• The theory of particle dynamics was introduced to focus on the distribution of crystals in the DTB crystallizer.
• Leading to an improved prediction of crystal growth , the growth kinetic model was introduced by loading the UDF program.
• Pure liquid phase methanol was taken to simulate the temperature change of the selected DTB during the cooling process.
The suspension state of crystals in the crystallizer is one of the important indicators for evaluating the adaptability of the crystallizer. This study adopted the Euler-Eulerian two-fluid model to simulate and analyze the fluid motion of solid-liquid two-phase flow in the industrial-grade DTB crystallization kettle, as well as the phase suspension distribution of crystal particles. The main influencing factors investigated are: the heat transfer effect, the height of the bottom of the crystallizer, the number and position of the stirring paddle, crystal size and crystal volume fraction. Based on the research of Euler-Eulerian method to simulate fluids, the Euler-Lagrangian method was further used to simulate the motion state of particle phases with different particle sizes in the crystallizer. It was found that the designed DTB crystallizer has good recycle mixing effect. The particles can be mixed evenly during the operation, which can fully realize the solid-liquid mixing and suspension effect of the drug under study.