关键词: 甲醇燃料, 烟叶烘烤, 引射器, 摩尔引射系数, 结构改进

Abstract: As a clean liquid energy source, methanol is an effective way to realize the intelligent green baking of agricultural products such as tobacco. However, the heat demand changes greatly at different stages of tobacco curing, resulting in poor stability and environmental temperature adaptability of the existing lowpower methanol burner. In this paper, a lowpower methanol burner for tobacco curing was designed. Numerical simulations were conducted to analyze the performance of the methanol burner ejector. The influences of nozzle diameter, nozzle position, diffuser length, pipe length, and primary air inlet diameter on ejector performance were investigated under different fuel inlet mass flow rates. The research findings reveal a negative correlation between the molar ejector coefficient and nozzle diameter, as well as a positive correlation with the primary air inlet diameter. Based on an analysis of the various structural parameters, improved design parameters for the methanol fuel burner ejector were obtained. When the fuel inlet mass flow rate was between 0.68 kg/h and 9.20 kg/h, the improved burner maintained a stable molar ejection coefficient between 1.95 and 4.41. Compared with the original design, the average molar ejection coefficient of the burner was increased by 49.7%. Furthermore, the improved ejector exhibited good temperature adaptability, ensuring that the exit temperature remains above the dew point temperature of methanol fuel even at lower fuel and ambient temperatures, which was conducive to stable combustion of methanol burner.

Key words: methanol fuel, tobacco curing, ejector, mole ejecting ratio, structural improvement