Flow Field Simulation And Optimization Of Horizontal Spiral Dryer With Rotatory Conical Jacket

Chlorosilane solid-liquid mixture is mainly consist of chlorosilane and Silica.The conventional treating processes such as washing are unable to recycle the chlorosilane in the slurry,resulting in material waste. Generally,the slurry is pretreatment in the airtight dryer to separate the chlorosilane from the slurry. Therefore, a continuous dryer is developed,which is very important for the chlorosilane recovery and ensuring continuous and safe production.3-D flow field with different internal and external ribbon pitch, stirring speed,viscosity inlet velocity were calculated and optimized.The results showed that external ribbon had larger stirring influence on the fluid,leading to a lager velocity in the region outside the cone compared with that in the region inside the cone. Vortex and boundary layer separation appeared at the back of ribbon and the spoke bar. The ratio between internal ribbon pitch and internal ribbon diameter was defined as ξ₂ and that between external ribbon pitch and external ribbon diameter was defined as ξ₁ ξ₂ which is equal to 0.9,1.0,1.2,1.33 and ξ₁ which is equal to 0.9,1.0,1.13 were studied in this paper.It was found that stirring effect increased with lager internal ribbon pitch and then decreased rapidly.In order to gain a better stirring efficiency,internal ribbon with ξ₂ 1.0was recommended. The fluid turbulence and torque increased with lager ξ₁. Taking both energy consumption and flow field into consideration, external ribbon with ξ₁ 0.9or 1.0 was recommended.Rotation speed which is equal to 5r/min³0r/min, viscosity which is equal to0.0034 sPa × 34 sPa × and inlet velocity which is equal to 0.1m/s⁰.3m/s were used to simulate the flow field in the dryer. The results showed it was suitable for the stirring system to turn at 10-15r/min and the torque required increased with fluid viscosity and the rate of change of torque was gradually advancing.Inlet velocity had little influence on the flow field distribution.General heat transfer calculation method and detailed algorithm of continuous heat transfer equipment were obtained. The dispersion rate was introduced to represent the change of heat transfer area for working condition compared with that for static state.The RTD curve, as well as the residence time and velocity distribution.was obtained by tracking the particle pathline.The distribution of heat transfer coefficientK and heating curve of the slurry were obtained by calculation and fitting formula was given to provide theoretical foundation of engineering application of the dryer.