Location: Stored Product Insect and Engineering Research
Project Number: 3020-43440-010-003-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Apr 1, 2016
End Date: Mar 31, 2021
Objective:
Extend current discrete element method (DEM) and computational fluid dynamics (CFD) models of grain handling and storage to additional applications: (1) DEM modeling of compaction of corn during uniaxial compression tests and (2) CFD modeling of fumigant and aerosol distribution.
Approach:
Our current model of compaction in stored grain is based on laboratory measurements of the bulk behavior of grain compressibility versus overburden pressure. The relative effect of different mechanisms of particle rearrangement and particle compression during compaction are not known. The compressibility phenomena in the laboratory uniaxial compression tester will be modeled using DEM to study the individual particle movement (rearrangement) and compaction that produces the well-known bulk compaction of the grain. This detailed knowledge of the particle level processes leading to bulk compaction can be used to better predict compaction in grain bins.
CFD modeling of gaseous fumigant dispersal in grain bulks and aerosol dispersal in warehouses can effectively reveal the detailed mechanisms of movement that result in failed fumigations or aerosol treatments, but which are difficult or impossible to determine in experiments. Fumigation and aerosol treatment methods necessarily rely on various convection currents, diffusion mechanisms, and particle dynamics to distribute the gas or droplets. When those mechanisms are inadequate in any part of the treated space, the resulting low dosage causes failure of the treatment and survival of some targeted pests. CFD models will be developed to investigate phosphine dispersal in bulk grain storages and aerosol movement in warehouse applications.
