户用太阳能辅助加热沼气池动态传热仿真  

Numerical Simulation of Unsteady Heat Transfer in Solar-assisted Heating Household Biogas Digester

作　　者：郭甲生[1] 秦朝葵[1] 魏晓峰[1] 唐继旭[1] 

机构地区：[1]同济大学机械工程学院,上海201804

出　　处：《计算机仿真》2011年第1期360-364,共5页Computer Simulation

基　　金：国家"十一五"科技支撑计划项目(2006BAJ04B02-01)

摘　　要：针对态变温差条件下螺旋管换热器传热系数计算复杂,而螺旋管换热器传热系数是户用太阳能辅助加热沼气池系统设计中的重要参数。为确定沼气池内加热盘管的传热系数及合理的搅拌叶轮旋转速度,采用全三维Navier-Stokes方程和多重参考系法(MRF),根据标准k-ε湍流模型及相应的计算网络及边界条件,对沼气池内传热及流动进行三维非定常数值仿真,分析系统的传热系数,随着旋转叶轮转速提高,螺旋加热盘管传热系数也随之增加,但旋转叶轮所需电机功率也将随之增大。通过数值仿真,可以大大缩短系统的研制和改进设计周期,结果与现场实测传热系数有较好的吻合。证明提高了沼气池内螺旋盘管的加热效果,并为系统设计提供参考依据。The heat transfer coefficient of spiral tube exchanger in unsteady condition is hard to obtain, while the heat transfer coefficient of spiral tube exchanger is of great importance in design of solar-assisted heating household biogas digester system. The development and design cycle and cost of solar-assisted heating household biogas digester system can be cut down greatly with the support of numerical simulation. In this paper, studies were carried out on the three-dimensional unsteady numerical simulation of heating process in biogas digesters by using computational flu- id dynamics （CFD） , the multi-reference frame （MRF） and standard κ-ε turbulent model were used in the simula- tion. The simulation result indicates that heating coil heat transfer coefficient can enhance significantly with the use of stirring device in biogas digesters. With the increase of rotating impeller speed, heating coil heat transfer coefficient increases, however, the rotating impeller motor power requirements also increases. The heating coil heat transfer co- efficient simulation result has a good match with the field test result. The results are of importance to the design of SHHBDS.

关 键 词：太阳能 沼气池 搅拌装置 传热系数 数值模拟 

分 类 号：TK515[动力工程及工程热物理—热能工程]