Numerical Simulation On Screw Extruder Of Straw

Straw is an important raw material of biomass source, the key technology of using straw to make biomass ethanol fuel has matured and gradually improved and optimized. Usually the straw should be washed and soaked after the straw collection, transportation and pulverization to remove gravel, metal chips and other contaminants, then the straw should be dehydrated in order to meet the follow-up device’s requirement of the moisture content of raw material. At present, the more commonly used equipment for dewatering the straw after soaking is screw extruder, although it is widely used actual in the project, but the theoretical research of the device is few. The theoretical study of straw screw extruder has important guiding significance to design and manufacture as well as to improve its performance, therefore it is necessary to study its theory.With the development of numerical simulation techniques, the use of engineering software to solve engineering problems are received more and more attention. In this paper, ANSYS simulation software has been used to investigate a self-designed straw screw extruder.First, Fluent CFD engineering software has been used to research the variation of the pressure field of the internal full-flow channel of the device. A fluid model of straw slurry is established, a full-flow channel three-dimensional solid model is established and then the model has been meshed, after importing into the Fluent and calculating, the pressure field distribution map of the internal full-flow channel of the device has been obtained, then the variation of the pressure field inside the device has been analyzed.Then, Fluent has been used to simulate the internal pressure field by varying the different outlet pressures, different rotational speed of screw shaft and different compression ratios, the influence of these parameters on the internal pressure field has been obtained, and then the influence of these parameters on the performance of the device has been analyzed.Finally, a one-way flow-structure interation analysis for the straw screw extruder has been conducted based on the ANSYS Workbench platform, then the results of the pressure field analysis has been introduced into the solid structural strength analysis, stress distribution map and displacement response map of helical blades under different outlet pressure and different thickness of blade have been obtained by applying constraints and load of the main pressure receiving surface of the helical blades, accordingly strength and deformation of the helical blade have been analyzed, and then the influence of the strength and deformation of the helical blade based on the different outlet pressure and different thickness has been obtained.