Optimization of geometries shell and tube heat exchanger to minimize fouling resistance by utilizing polley threshold model

One of the methods to mitigate fouling is to determine the optimal geometries of the heat exchanger. In this research, optimization of heat exchanger design was performed by determining shell and tube heat exchanger geometries. In this optimization require three components i.e. fouling and heat exchanger model, problem formulation and optimization technique. Fouling model was built by utilizing Polley fouling model. The objective function of optimization minimizes fouling resistance by determining shell and tube heat exchanger geometries, with constraints available heat duty and allowable pressure drops. Since the optimization falls into mixed-integer nonlinear problems that have some local optimum, the optimization technique has the capability to find out the global optimum is required. The selected optimization variables are shell side diameter (Ds), tube outside diameter (do) and the number of baffles (Nb). Optimization results showed that shell side fouling resistance was reduced by 17%, tube side was reduced by 48% compared with existing design by considering available heat duty and allowable pressure drops.