CFD Study of Fluid Characteristic and Heat Transfer in Tubes with Disturbance Bodies

Low-Pressure Heater (LPH) is a type of shell & tube heat exchanger that used as a feed water preheater that will enter the boiler with steam turbine extraction as a heater. The tubes in LPH are arranged very tightly to maximize the heat transfer process, so that the resulting pressure drop is very large. There are two methods to reduce the pressure drop that occurs, that is the active control and passive control methods. The passive control method used the inlet disturbance body (IDB) on the upstream tube side. This research was conducted with 2D numerical simulation method, using computational fluid dynamic (CFD) software. The purpose of this study was to know about the flow characteristic of the LPH tube with the addition of IDB. The simulation test model is in the form of five LPH tubes arranged staggered and the variations are without IDB, cylindrical IDB, and rectangular IDB. Simulation results show that the basic variations, it is without IDB. It can reduce more pressure drop on LPH compared to using cylindrical IDB, and rectangular IDB. This is proven by the results of the smallest drag coefficient value of 0.0769 and the value of the drag coefficient increases as disturbance body angle increasing. Besides that, it is also supported with a wake speed profile of 0.21 m/s and a Nusselt number of 45.88.