Thermal Design Characterization of Heat Exchangers for 3 Stages Turbo Centrifugal Geared Air Compressor

Abstract

A single or multi stage turbo centrifugal geared compressor is widely used in various industrial application such as oil & gas, chemical, power, and air separation plants. It is consist of compression part including air scroll, impeller, and diffuser, gear and bearing, cooling, oil, sealing, and control systems. Shell and tube type heat exchanger commonly used to cool down compressed gas or air between stages or after final stages, and supply oil temperature as a cooler. On compressor’s cooling system strongly required to compact (miniaturization) and high heat transfer capability. Increases of heat transfer capability can result reduce compression aero-power and pumping-power, enhance system stability, and compact. Recently, nanofluid, which is a colloidal dispersion of nano-sized particles in basefluid such as water, ethylene-glycol, propylene-glycol and their mixtures etc., exhibit a significant enhancement in their thermal conductivity. Thus, using nanofluida expected to be an advanced coolant material in compressor cooling system. In this study, HTRI Xist used to thermal design of heat exchanger, nanofluid’s thermal conductivity used to coolant material property. The thermal conductivity of the nanofluid increased by 9.3% compared to that of water. The heat exchanger’s tube side overall heat transfer rate is increased by ~7% compared to that of basefluid