加热位置对沼气罐温度场影响的实验和模拟

Experiment and simulate influence of heating position on biogas tank temperature field

为了使沼气罐内有一个相对均匀的温度环境、提高沼气的产气效率,通过改变沼气罐内的加热位置,找出能使沼气罐内温度场均匀的加热位置,减小罐内温度梯度过大对发酵造成的影响。用实验研究和数值模拟相结合的方法,研究沼气罐内的温度场分布情况,结果表明,中部加热较上部加热和下部加热能取得良好的罐内温度场,温度梯度较小,使罐内上、中、下各部分温度分别维持在33.95、34.02和33.6℃,比传统的采用下部换热能取得更好的温度场。

To maintain a relatively steady environmental temperature and improve the efficiency of biogas production,the temperature field distribution in a biogas tank was studied by changing the position at which heating was applied. The goal was to find the location from which heating could provide a uniform temperature field and minimize the impact of an overly steep temperature gradient on the fermentation process. With a combination of experimental study and numerical simulation,the temperature field in the tank was studied and the results showed that centrally located heating could obtain a better temperature field than with upper or heating locations.Moreover,central heating could keep the temperature of upper,central,and lower areas at 33. 95,34. 02,and 33. 6 ℃,respectively. This results in a lower temperature gradient and gets a better temperature field than that obtained with traditional heating in the lower area.