Research Of Sampling System’s Key Techniques For Bulk Grain Loaded By Truck

Along with the advance of science and technology, people’s standard of living isincreasing day by day, and people is becoming more and more attention on the problem offood safety. Grain as raw materials of various kinds of food, especially in the large flour mills,examination of the food quality is more important which is one of the important steps ofcorrect classification to determine the quality of food grade. Trucks are important means oftransport carrying bulk grain, therefore picking up the most representative sample is urgent tosolve for bulk vehicle.As an important part of a sampling system, spear largely determines the quality of theselected samples. The paper mainly improves the key technology of the automatic samplingsystem to be more appropriate for the conditions of domestic and improve the efficiency ofstand samples on the basis of the domestic and international bulk grain. It mainly includes thefollowing several aspects: firstly, structural design of spear is mainly researched and a newtype of spear which is named the coaxial spear is successfully designed. Secondly, pneumaticconveying system is designed according to the structure and operating principle of the coaxialspear. Thirdly, the two-dimensional Gas-solid two-phase model of turbulence are establishedusing the computational fluid dynamics software Fluent to make the preparation for thenumerical simulation of two phase flow in vertical coaxial spear, numerical simulation studyfor the structural parameters affecting the flow field is carried on and Gas-solid two-phaseflow field is compared about the coaxial spear and the single flow spear to provide somereferences for the design of the coaxial spear. Finally, the test is done for verifying the resultsof simulation to provide actual evidence structure of the coaxial spear.