Abstract: Computational Fluid Dynamic (CFD) is a useful tool in solving and analyzing problems that involve fluid flows, while shell and tube heat exchanger is the most common type of heat exchanger and widely use in oil refinery and other large chemical processes because it suite for high pressure application. The numerical simulation of Shell & Tube Heat Exchanger with center tube called Helixchanger with center tube with different baffle inclination is to be done. The processes in solving the simulation consist of modeling and meshing the basic geometry of Helixchanger using the CFD package ICEM CFD. Then, the boundary condition will be set before been simulate in Fluent based on the research papers experimental data. Finally results has been examined in CFD-POST. Parameter that had been used was the same parameter of experimental at constant mass flow rate of hot water and varies with mass flow rate at 50,60,70 & 80 LPM of cold water. Thus, this report presents the simulation of heat transfer & pressure drop in Helixchanger model with different baffle inclination as 20, 25, 30 & 40 degree, which gives insight of all parameters affect on Helixchanger design & it also suggests the optimized helix angle which gives better heat transfer with minimum pressure drop.