With the increasing need for more efficient industrial gas turbine engines, the recuperated engine cycle is being considered as a means of meeting these needs.
This paper discusses a recuperated cycle design that is optimized to take full advantage of the recuperator but at the same time accommodate the real world market constraints of reliability, durability and cost.
Current simple cycle industrial engines are evolving to very high pressure ratios and high firing temperatures in order to reach cycle efficiencies in the 37% to 39% range. Some simple cycle industrial gas turbines with lower cycle pressure ratios and firing temperatures have been modified so a recuperated option can be added. Although the addition of a recuperator to these engines does improve cycle efficiency, levels of only the 33% to 35% range are reached. This is mainly due to the fact that the resulting cycles are not optimized for a recuperator.
An engine cycle that is optimized around a recuperator could obtain cycle efficiencies in the 43% to 45% range. Fortunately, this cycle optimizes at low pressure ratios and modest firing temperatures which results in lower cost components which tend to offset the additional cost of the recuperator.
