Almost every industry handles one and often more bulk solids in production plants. In the chemical industry alone, an estimated 60% of products are manufactured as particulates, and another 20% use powders as ingredients to impart specific end-use properties. The US Department of Commerce has estimated the total economic impact of bulk solids products to be $1 trillion/year. Problems associated in plants that store, process or handle bulk solids are widespread and costly. Having a reliable predictive model to determine the behavior of bulk solids in industrial applications can avoid or fix many such problems. Some examples where a predictive model would be very beneficial to have are: seed storage and distribution, harvesting and spreaders in agriculture; cement mixing and earth moving equipment design in the construction industry; coal transport and catalytic cracking in the energy sector; powder mixing, tablet compaction and pill dispensing in the pharmaceutical industry; processing vessels, dryers, reactors in the chemical industry; and rock cutting, drag lines and conveying in the mining industry. Having an accurate computer model could save time and money in the design process and result in better products and lower risks. A robust, accurate simulation capability for bulk granular materials can help NASA in the prediction of stress/strain shearing and compaction response of insulation materials inside the annular space of large cryogenic liquid fuel storage tanks. The current insulation material degrades over each mission requiring frequent, costly replacement. By properly characterizing small samples of the insulation material and then combining DEM and FEA, a model of the insulation in the large tank can be created, which can help NASA evaluate alternative insulation materials with fewer costly physical tests and reduced uncertainty and risk. A second application is to develop a computer model for the mechanical behavior of lunar soil during drilling and digging, construction and compaction (of berms), or during beneficiation and chemical processing of the soil (e.g., to remove water ice). It is impossible to reproduce the combination of lunar gravity and regolith in an earth-based experiment, so accurate computer models are critical. The success of future missions which involve construction and in-situ resource utilization on the moon or Mars will depend on the accuracy of the models.
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