Experimental analysis of pressurised humidification tower for humid air gas turbine cycles. Part B: Correlation of experimental data

Abstract

One of the most interesting methods of water introduction in a gas turbine circuit is represented by the humid air turbine cycle (HAT). In the HAT cycle, the humidification can be provided by a pressurised saturator (i.e.: humidification tower or saturation tower), this solution being known to offer several attractive features. This work is focused on an experimental study of a pressurised humidification tower, with structured packing inside. After a description of the test rig, carried out in part A, this part B is concerned with the attempt to correlate all data points collected. Two different approaches have been used, the first based on polynomial correlation and the second using a set of new non-dimensional groups. The first correlation is shown to better fit the data, having lower standard deviation, but the second provides better interpretation of physics: the latter is able to capture the air outlet temperature with a standard deviation σ = 2.8 K. The correlations are useful for describing the off-design behaviour of the pressurised saturation tower and they can be used as generalised representations of the behaviour of structured packing humidification towers for HAT application, at least within the investigated operational range.