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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 SHUANGLIN SONG1,2, SHUGANG
WANG1*, 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 Received:
15 January 2017/Accepted: 21 May 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;
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