Optimization of Shazand Arak power plant boiler rifled tubes using genetic algorithm

Increase in pressure drop due to the use of rifled tubes and also increase the heat transfer coefficient in two-phase flow and during boiling length (single-phase region) caused that using evolutionary genetic algorithm to optimize the parameters of rifled tubes, with the goal of increasing the heat transfer coefficient over the single-phase region and reduce the pressure drop in natural circulation system of drum should be dicussed in this paper. Choice of objective function was done with respect to the analysis of the pressure drop in each part of the drum circle and its large changes relative to the change of rifled tubes parameters. The optimization was done using two scenarios based on constant number of tubes (scenario I) and constant mass flux (scenario II). The results showed that the design in case of constant number of tubes which is defined base on no changes in length and width of the Shazand Arak power plant boiler, led to reduce the height of boiler from 60m to 27.23m. Finally, the role of rifled tubes parameters and mass flux in this scenario relative to first scenario in reduce of pressure drop was led to set values of the rifled tubes parameters.