THERMAL SCIENCE

International Scientific Journal

Thermal Science - Online First

Authors of this Paper

External Links

online first only

Analysis of flow field and temperature distribution in granary under novel ventilation systems based on fractal structure

ABSTRACT
The distribution of velocity and temperature field inside the granary can be used to evaluate ventilation quality. A well-ventilated system with uniform airflow and cooling can effectively prevent moisture accumulation. To address the issue of poor uniformity in ventilation and cooling, this research introduces two new ventilation systems: the non-fractal ventilation system and the fractal ventilation system. The fractal structure was designed based on optimized parameters obtained from rectangular elements with minimum flow resistance. Numerical simulation methods were employed to verify the effectiveness of these ventilation systems. A comparative analysis was conducted, examining the velocity field, temperature field, and velocity uniformity of the two systems. The results demonstrated that the presence of a sand packing zone helped the grain pile zone avoid most of the areas with poor ventilation. The discontinuous pores at the interface between the sand packing zone and the grain pile zone significantly increased flow resistance, effectively reducing the velocity of high-speed ventilation into the grain pile zone and decreasing the permeability of the grain pile zone towards the poorly ventilated areas of the sand pile zone. Furthermore, the fractal structure greatly enhanced ventilation intensity in areas with poor ventilation in the velocity field, while also improving the uniformity of cooling in the temperature field. This research presents an innovative solution for ventilation in room-type warehouses, offering a new option for effective and efficient ventilation.
KEYWORDS
PAPER SUBMITTED: 2023-08-07
PAPER REVISED: 2023-09-20
PAPER ACCEPTED: 2023-09-30
PUBLISHED ONLINE: 2023-11-11
DOI REFERENCE: https://doi.org/10.2298/TSCI230807238L
REFERENCES
  1. Gao Liwei., Characteristics and Reduction of Potentials of Loss and waste of Major Grains of the Food Supply Chain in China, Chinese Academy of Agricultural Sciences, Ph. D. thesis, Beijing, China, 2019 (in Chinese language).
  2. Cui Jinbo., Population Ecology of Major Stored Product Insect Pests in Large Warehouse, MA.Sc. thesis, South Western University of Finance and Economics, Chongqing, China, 2006 (in Chinese language).
  3. Graham R. Thorpe., On the rate of cooling of aerated food grains, Biosystems Engineering, 2022, 222, pp. 106 116
  4. Liu Shuling, Wu Zengqiang., Granary ventilation systems and methods, Chinese Patent: 201510608233.4, 2017--03--29 (in Chinese language).
  5. Li Jiabin, Wang Yuancheng, Liu Jiaqi, et al., Simulation Study on the Ventilation Effect of a New Type of Ventilation Network on Room--Type Warehouses, Science and Technology of Cereals, Oils and Foods. 2023, 31(1), pp. 189--195 (in Chinese language).
  6. Xiong Disheng., Dewdew formation in grain piles with mechanical ventilation and its prevention, Food Science and Technology and Economy, 1999, (4), pp. 25--27 (in Chinese language).
  7. Code for Design of Grain Bungalows, Beijing China Planning Publishing House, www.sosoarch.com/guifan/details.aspx?id=260 (in Chinese language).
  8. G. R. Thorpe., The application of computational fluid dynamics codes to simulate heat and moisture transfer in stored grains, Journal of Stored Products Research, 2008, 44(1), pp. 21--31
  9. G. R. Thorpe., The modelling and potential applications of a simple solar regenerated grain cooling device, Postharvest Biology and Technology, 1998, 13(2), pp. 151--168
  10. Daniela de Carvalho Lopes, et al., Aeration simulation of stored grain under variable air ambient conditions, Postharvest Biology and Technology, 2006, 42(1), pp. 115--120
  11. Olatunde Gbenga,Atungulu Griffiths G,Sadaka Sammy., CFD modeling of air flow distribution in rice bin storage system with different grain mass configurations, Biosystems Engineering, 2016, 151, pp. 286--297
  12. Xiangxiang Zhang,Hao Zhang,Zhenqing Wang, et al., Research on the temperature field of grain piles in underground grain silos lined with plastic, Journal of Food Process Engineering, 2022, 45(3)
  13. Tareq Salameh, Mamdouh El Haj Assad, Muhammad Tawalbeh, et al., Analysis of cooling load on commercial building in UAE climate using building integrated photovoltaic façade system, Solar Energy, 2020, 199, pp. 617--629
  14. Chen Lingen, Tian Fenghong, Xiao Qinghua, et al., Constructal entransy dissipation rate minimization for mass transfer based on rectangular element with constant channel, Journal of Thermal Science and Technology, 2012, 11(2), pp. 136--141
  15. A. Bejan,M. R. Errera., Deterministic Tree Networks for Fluid Flow: Geometry for Minimal Flow Resistance Between a Volume and One Point, Fractals --london--, 1997, 5(4), pp. 685--696
  16. Huijun Feng,Lingen Chen,Zhihui Xie, et al., "Volume--Point" Mass Transfer Constructal Optimization Based on Triangular Element, Arabian Journal for Science and Engineering, 2013, 38(2), pp. 365--372
  17. Adrian Bejan., Constructal theory: from thermodynamic and geometric optimization to predicting shape in nature, Energy Conversion and Management, 1998, 39(16), pp. 1705--1718
  18. Liu Han., Comby fractal microchannel network for fluid flow in porous media, MA.Sc. thesis, Huazhong University of Science and Technology, Wuhan, China, 2014 (in Chinese language).
  19. Yuancheng Wang,Haifeng Duan,Hao Zhang, et al., Modeling on heat and mass transfer in stored wheat during forced cooling ventilation, Journal of Thermal Science, 2010, 19(2), pp. 167--172
  20. Chen Baoming, Liu Fang, Yun Heming., Natural Convective Heat and Mass Transfer in Porous Media, Science Press, Beijing, China, 2016 (in Chinese language).
  21. Adrian Bejan., Constructal tree network for fluid flow between a finite--size volume and one source or sink, Revue Générale De Thermique, 1997, 36(8), pp. 592--604
  22. Errera M.R, Bejan Adrian, Tree Networks for Flows in Composite Porous Media, Journal of Porous Media, 1999
  23. Wang Zhenhua. Numerical Simulation and Experimental Study on Heat and Mass Transfer of Stored Grain Pile, Ph. D. thesis, China Agricultural University, Beijing, China, 2014. (in Chinese language).
  24. H. Weltens, H. Bressler, F. Terres, et al., Optimisation of Catalytic Converter Gas Flow Distribution by CFD Prediction, International Congress & Exposition, 1993