Journal Article

Design Research of a Novel Aftercool-Humidifier Concept for Humid Air Turbine Cycle

Zhang, Junzheng, Xu, Zhen

2024

Overview

Humid air turbine cycle (HAT) has potential of electrical efficiencies comparable to combined cycle, with lower investment cost and NO x emission. The typical heat exchanger network of HAT consists of intercooler (if there is), aftercooler, recuperator, economizer and humidifier, which brings higher efficiency but makes the system more complex. To simplify HAT layout, a novel humidifier concept is proposed by integrating the aftercooler into traditional counter-current humidifier. Based on this concept, a one-dimensional model including pressure drop and exergy calculation is established to distinguish the thermodynamic and hydrodynamic characteristics, and then the structural parameters, such as the number of rows and columns, tube diameter, pitch and type for a micro HAT are identified. The results show that the aftercool-humidifier plays the same role as original aftercooler and humidifier, and can match the in-tube air, out-tube air and water stream well with lower volume. In the case of micro HAT cycle, the volume of heat and mass transfer area can be reduced by 47% compared with traditional design. The major thermal resistance occurred in the convection heat transfer process inside the tube; however, using enhanced tube cannot effectively improve the compactness of device.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V
• Subject: Accuracy / Classical and Continuum Physics / Coolers / Efficiency / Emissions / Engineering Fluid Dynamics / Engineering Thermodynamics / Entropy / Exergy / Gas turbines / Heat and Mass Transfer / Heat exchangers / Heat transfer / Humid air turbines / Mass transfer / One dimensional models / Physics / Physics and Astronomy / Pressure drop / Reynolds number / Thermal resistance / Turbines / Water