# Virtual Prototyping of Bulk Material Preparation Devices in Mining Using Multiphysics Simulations
## 1 Introduction
### Mining Industry  
The mining industry is a key source of raw materials for other industries. For example, coal mining is necessary to produce electricity and heat. Oil extraction is also crucial for the production of fuels, plastics, and many other products. The mining industry also provides raw materials for the production of metals such as gold, silver, and copper, which are used in electronics, construction, and many other industries [1; 2]. The products of the mining industry (mineral raw materials) are divided into the following groups:  
* Metallic: ferrous (e.g., iron ore, manganese, nickel, cobalt); non-ferrous (e.g., copper, lead, tin, bauxite); precious metals (e.g., gold, silver, platinum);
* Non-metallic (e.g., rock salt, potassium salt, sulfur, granite, marble, limestone, aggregates);
* Mineral raw materials for energy production (hard coal, brown coal, crude oil, natural gas) [3]. The extracted raw mineral is a mixture of grains of various sizes and shapes and with different mineral compositions. The material in this form is usually not suitable for direct use; therefore, it should be subjected to processing to obtain optimal and acceptable commercial parameters [4]. The analysis of the volume of mineral resource extraction indicates significant potential for the development of the machines and equipment intended for the processing of the above-mentioned materials. For example, iron ore production in 2023 amounted to 2398.3 million tons, and the main shareholders were Brazil, China, Russia, India, and Australia [5; 6]. In turn, the total global production of manganese in 2021 was 49.5 million tons, and the largest producer in the world was South Africa [7]. The highest extraction volume is the case of sand and gravel. According to online sources and UN analyses, 50 billion tons of these materials are mined every year [8]. In mechanical processing, the task of which is to separate the cleanest possible useful grains from the raw material and the cleanest waste grains devoid of a useful component, three basic operations can be distinguished [4]: classification--as a result of which the material is separated into groups of grains with specific dimensions; beneficiation--the aim of which is to divide the material into groups of grains with the same mineral characteristics; crushing--reducing the size (breaking into smaller parts) of the grains. Dimensional classification of raw minerals mostly uses screening machines. These devices are used in the processing the raw minerals at many stages of the technological process, not only for the dimensional classification of raw material but also for the dewatering of some beneficiation products, as well as the dimensional classification of final (commercial) products. Screening machines play a significant role in iron ore processing, which is why various types of the above devices are available on the market [9; 10; 11]. Screeners are one of the main machines used in aggregate processing. Much of this material is subjected to preparatory operations before its use, including dimensional classification. There is a very large number of companies that have their devices available for this purpose [12; 13; 14]. Screeners are also very often used in the hard coal mining industry, and even in the metallurgical industry (coke screening) [15; 16; 17]. Another example shows that screens are also important in the processing of salt rocks [18]. In the case of the second main operation of minerals processing, i.e., beneficiation, water pulsating jigs, using the phenomenon of the density separation of particles, are the devices most commonly used. Separation takes place in a pulsating water stream based on differences in the settling rates of the grains being beneficiated. Water pulsating jigs are the devices commonly used in hard coal beneficiation [19; 20; 21; 22; 23] and washing the aggregates [24; 25]. Important areas of jig application include iron ore [26; 27; 28; 29] and manganese ore [30; 31].