The ACTE Spiral Recuperator for Gas Turbine Engines

Abstract

A new recuperator is now being introduced for small and micro-turbine applications. These applications are characterized by low pressure ratios, exhaust gas temperatures that are suitable for use with stainless steel, and a limited allowance for leakage that does not impair the performance. However high reliability is required, because microturbines typically experience 4000 start/stop cycles during their life, and have to be totally reliable when supplying electricity for applications that are independent of the grid. Recuperated gas turbines have a history of expensive installations, prone to cracking under thermal shocks. The ACTE recuperator has been specifically designed for reliablity, compactness and low cost. This paper shows how these seemingly conflicting requirements are met in the ACTE design.

Heat transfer correlations and NTU number for the longitudinal flow spiral recuperators

“…The comparison of the Nusselt number values for the fullydeveloped laminar forced-flow (8) and the thermally and hydrodynamically developing laminar flow (9) and (22) is presented in Fig. 5.…”

“…This attractive compact recuperator is being developed for a range of gas turbine applications [8]. Development work in Belgium has progressed on an interesting high effectiveness spirally wrapped compact primary-surface recuperator with laser welded seals [9]. The unique headering of this unit involves locally opening air channels by a spark erosion process, and then welding the air side manifolds on to the two end faces of the core.…”

Recuperator dynamic performance: Experimental investigation with a microgas turbine test rig

“…The new compact heat recovery exchangers for microturbine applications, called primary surface recuperators, began to appear in the late 1970s in Germany [11]. Then, heat exchanger specialists studied and designed different recuperator concepts with the aim of [1]: Increasing recuperator performance [12]; reducing the number of parts; using low-cost manufacturing processes; increasing recuperator flexibility; achieving a better machine/recuperator integration level; developing new recuperator geometries [13] and new materials (i.e. : for superalloy or ceramic recuperators [12,14]).…”

Experimental Investigation of the Dynamic Performance of a Micro Gas Turbine Recuperator Including Innovative Cycle Configurations

“…• developing new recuperator geometries [12] and new materials (i.e. : for superalloy or ceramic recuperators [11] [13]).…”