THERMAL SCIENCE

International Scientific Journal

Thermal Science - Online First

online first only

Numerical simulation and experimental verification of stability on multi-cavity spiral cascade heat transfer system

ABSTRACT
In order to improve the insufficient effect of heat transfer in pyrolysis carbonization system and reveal the effects of velocity and temperature field of hot flue gas on heat transfer and stability in the biomass, the structure with rectangular groove combined with a spiral baffle is designed to form a multi-cavity spiral cascade heat transfer system. Numerical simulation and experimental verification of stability are carried on multi-cavity spiral cascade heat transfer system. The results show that the hot flue gas with high temperature flows fast at the inlet and outlet, while the flow speed is slow and stable in the cavity of heat transfer. The temperature of hot flue gas reaches the highest at the entrance, and decreases in the heat exchange chamber in a cascade. The spiral inclination angle of 35° and the pitch of 1.2m. The combustion of gas produced by pyrolysis of raw materials can meet the requirement of continuous and stable operation, when the temperature of monitor point 1, 3, 6 and 8 reaches 800 ℃, 530 ℃, 250 ℃and 200 ℃ respectively. The temperature of hot flue gas changes fluctuate in the range of 15 ℃. The combustion of pyrolysis gas generated during the pyrolysis process of raw materials can ensure the continuous and stable operation of the equipment.
KEYWORDS
PAPER SUBMITTED: 2020-06-25
PAPER REVISED: 2020-09-04
PAPER ACCEPTED: 2020-09-28
PUBLISHED ONLINE: 2020-10-31
DOI REFERENCE: https://doi.org/10.2298/TSCI200625319L
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