Sains Malaysiana 46(11)(2017): 2143-2148

http://dx.doi.org/10.17576/jsm-2017-4611-15

Influence of Air Supply Velocity on Temperature Field in the Self Heating Process of Coal

(Pengaruh Halaju Bekalan Udara pada Bidang Suhu dalam Proses Pemanasan Sendiri Arang Batu)

SHUANGLIN SONG^1,2, SHUGANG WANG^1*, YUNTAO LIANG², XIAOCHEN LI¹ & QI LIN¹

¹Faculty of Infrastructure Engineering, Dalian University of Technology, Dalian 116024, China

²State Key Laboratory of Coal Mine Safety Technology, CCTEG Shenyang Research Institute

Shenyang, 110016, China

Diserahkan: 15 Januari 2017/Diterima: 21 Mei 2017

ABSTRACT

The air supply velocity is an important factor affecting the spontaneous combustion of coal. The appropriate air velocity can not only provide the oxygen required for the oxidation reaction, but maintains the good heat storage environment. Therefore, it is necessary to study the influence of the actual air velocity in the pore space on the self-heating process of coal particles. This paper focuses on studying the real space piled up by spherical particles. CFD simulation software is used to establish the numerical model from pore scale. Good fitness of the simulation results with the existing results verifies the feasibility of the calculation method. Later, the calculation conditions are changed to calculate and analyze the velocity field and the temperature field for self-heating of some particles (the surface of the particles is at a certain temperature) and expound the effect of different air supply velocities on gathering and dissipating the heat.

Keywords: Coal self-heating; flow field; pore scale; self-heating point; temperature field

ABSTRAK

Halaju bekalan udara adalah faktor penting yang mempengaruhi pembakaran spontan arang batu. Halaju udara yang sesuai bukan sahaja dapat memberikan oksigen yang diperlukan untuk reaksi pengoksidaan, tetapi mengekalkan persekitaran penyimpanan haba yang baik. Oleh itu, adalah perlu untuk mengkaji pengaruh halaju udara sebenar di ruang liang pada proses pemanasan sendiri zarah arang batu. Makalah ini memberi tumpuan kepada mengkaji ruang sebenar yang ditimbun oleh zarah sfera. Perisian simulasi CFD digunakan untuk menubuhkan model berangka daripada skala liang. Kesesuaian yang baik daripada keputusan simulasi dengan keputusan sedia ada mengesahkan kelayakan kaedah pengiraan yang digunakan. Kemudian, keadaan pengiraan diubah untuk mengira dan menganalisis medan halaju dan medan suhu untuk pemanasan sendiri beberapa zarah (contohnya permukaan zarah berada pada suhu tertentu) dan menjelaskan kesan halangan bekalan udara yang berlainan pada pengumpulan dan menghilangkan haba.

Kata kunci: Bidang aliran; medan suhu; pemanasan sendiri arang batu; skala lubang; titik pemanasan sendiri

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*Pengarang untuk surat-menyurat; email: sgwang@dlut.edu.cn