investigation of heat transfer parameters of a bundle of heaters in a simple bubble column reactor using cfd method

bubble columns are gas- liquid contactors that are widely used in chemical and bio- chemical industries. high mixing that result in high heat and mass transfer rates are amongst their advantages. heat transfer in a bubble column having a bundle of heaters investigated and the variation of heat transfer coefficient with variation in heaters pitch to diameter ratios in a bundle of heaters reported. the bubble column modeled in a three-dimensional in the eulerian framework by using computational fluid dynamic simulation. it was 0.292 m in diameter and 1.5 m in height.  simulations performed for five heaters and for nine heaters in a bundle. the bubble column with a five heaters bundle was investigated in the pitch to diameter ratios of 1.5, 2 and 2.5.  the bubble column with nine heaters bundle was investigated with the pitch to diameter ratios of 1.25, 1.5, 2.25 and 2.46. the range of the gas velocity was 0.0025 to 0.04 m/s. the heat transfer results show that, with decreasing the pitch to diameter ratios the heat transfer coefficient decreases. in bubble column with bundle of nine heaters at a constant superficial gas velocity, with decreasing the pitch to diameter ratio from 2.46 to 1.5 the heat transfer coefficient decreases; whereas in the pitch to diameter ratio of 1.25 heat transfer coefficient is high.