换热设备表面形成的微生物污垢严重影响了换热效率和系统安全。为了减少微生物污垢,需要研究微生物污垢的生长机理和受力特性。该文采用3维细胞自动机模型,对微生物污垢进行了生长模拟,并模拟了混合菌种的相互抑制。针对微生物污垢形状多样的特点,提出了形状因子的概念,分析了形状因子与受力的关系。该文细胞自动机模型采用了换热设备的代表性菌种——枯草芽孢杆菌和鳗鱼气单胞菌。采用该模型模拟两种菌种的生长机理和相互抑制,结果发现换热设备抑垢应侧重于枯草芽孢杆菌。该文提出的形状因子能较好量化污垢形状,有效地描述了3种典型污垢形状。形状因子简化了污垢形状与受力的关联分析,有助于不同形状污垢的对比。

Biofouling on heat exchanger surfaces reduces the heat transfer rate and the system security. Thus, more investigations are needed on biofouling growth mechanisms and the forces acting on the biofouling. This study uses a three dimensional cellular automata model to simulate biofouling growth. Reciprocal inhibition between different bacteria strains is also simulated. A shape factor concept is then used to describe the various biofouling shapes to analyze the forces on the biofouling. The cellular automata model simulates Bacillus subtilis and Aeromonas ichthiosmia as typical heat exchanger bacteria strains. The model simulates the biofouling growth and reciprocal inhibition to show that the heat exchanger biofouling inhibition should focus on Bacillus subtilis. The shape factors for three typical shapes used in this work accurately model the biofouling shapes. The shape factors simplify the force analyses and are useful for comparing different biofouling shapes.