CFD modeling of heat transfer and flow field in spin flash drying process
- PDF / 3,123,675 Bytes
- 11 Pages / 595.276 x 790.866 pts Page_size
- 29 Downloads / 209 Views
ORIGINAL
CFD modeling of heat transfer and flow field in spin flash drying process Yuejin Yuan 1 & Pengpeng Dong 1 & Yingying Xu 1 & Dong Wang 1 & Yueding Yuan 2 & Libin Tan 1 & Lingbo Kong 1 Received: 13 December 2019 / Revised: 4 July 2020 / Accepted: 13 July 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Spin flash drying equipment is widely used in chemical, food and other fields. Drying process consumes large amounts of energy and reduction in operating cost will be extremely beneficial for the industry. Therefore, in order to improve the efficiency of spin flash dryer. A three-dimensional CFD model of the drying process was established by computational fluid dynamics, and the flow field characteristics and heat transfer mechanism of the drying process were obtained. We studied the specific effects of different parameters on the drying process, and verified the results with calcium carbonate as raw material. The experimental results are basically consistent with the simulation results. The velocity, temperature and pressure in the drying chamber near the wall are greater than those in the central region, which generally decrease with height. The speed of the cutter set has a large effect on the tangential and radial velocity, but the influence on the pressure drop is not significant. Meanwhile the temperature and velocity of inlet air have a greater impact on distribution of flow field and material drying, the variable structure improves the stability of the drying process. Keywords Spin flash . Flow field . Drying equipment . Simulation
1 Introduction The drying process reduces both product moisture content and water activity, slows down microbial growth and enzymatic activity, extends food shelf life, and transportation and storage costs [1, 2]. Drying is applied amongst others for processing food [3, 4], textile, paper, wood, wastewater sludge, pharmaceutical products or biotechnological products [5]. The flash dryer is one of the most widely used drying systems. The dryer exposes the material to a high temperature turbulent flow for a short period of time (usually a few seconds), which allows water to evaporate quickly without overheating the material [6, 7]. This turbulence is also used as a conveyor system [8]. Flash dryers are used to dry most chemicals, foods, medicines, polymers, several by-products and minerals [9, 10]. The drying process consumes a lot of energy, so any improvement in * Lingbo Kong [email protected] 1
College of Mechanical and Electrical Engineering, Shaanxi University of Science and Technology, Xi’an 710021, China
2
College of Mathematics and Computer Science, Yichun University, Yichun 336000, China
the existing dryer design and the cost reduction will be very beneficial to the industry using the drying system [11, 12]. Numerical models using the CFD codes have been investigated and reported in industrial drying processes [13]. Various properties such as solids concentration, pressure [14], gas and solids of velocity [15], and temperature in the
Data Loading...
