Expanded Feed Thermal Characteristic Parameters Research And Drying By Numerical Simulation

Along with the development of feed industry, drying technology and equipment were put forward higher request by more and more feed producers. In order to adapt to the manufacturer's request, the design and research of dryer equipment focus on hugeness, serration, low energy consumption. Multi-storey vertical dryer is a new type of dryer, Its characteristic is:dry room with no mechanical parts, and daily maintenance need less; running continuously, high efficiency, high capacity≥10t/h;expensive. Drying is an important link in the feed manufacturing process, Air distribution mode in multi-storey vertical dryer is bottom air supply and sides supply. In this paper, following Patten of hot air in dryer chamber was researched; provide the reference to the optimization and improvement of vertical dryer.Firstly the thermal characteristics of expanded feed were studied, and then the air flow condition of multilayer vertical dryer was simulated by using computational fluid dynamics (CFD). Specific research as follows:1) Test material was a factory 3 expanded feed (002,556,561), using KD2 PRO thermal characteristic analyzer measure thermal conductivityλof expanded feed at initial temperature T(25℃,35℃,45℃)and 8 kinds of moisture content M. Thermal conductivity relations of coefficient were found out.2) Using quality volume method measure the porosity of expanded feed (556,561), two expanded feed' grain appearance are cylinder. Through the research of porosity, expanded feed grain size affect porosity smaller. Expanded feed together is often as a whole, actually there are many gaps between particles. Surface exists hole, make the surface tension become larger. These pore also not easily detected, so the values of porosity measured is small.3) Vertical dryer dry indoor model was established, the way of ventilation air side supply and bottom supply was focused on. The dry indoor air pressure distribution vector diagram, air pressure, wind velocity vector diagram, wind velocity distribution were found out. By anglicizing and researching numerical model, found out the best dry area of ventilation dry room model of bottom air supply is:X=0-400mm, Y=0-750mm and X=1500-2400mm, Y=1300-2400mm is best, the best dry area of dry room model of Sides supply is:X=0-100mm, Y=0-500mm and X=1800-2400mm, Y=1300-2400mm.