Review of modern low emissions combustion technologies for aero gas turbine engines

Abstract

Pollutant emissions from aircraft in the vicinity of airports and at altitude are of great public concern due to their impact on environment and human health. The legislations aimed at limiting aircraft emissions have become more stringent over the past few decades. This has resulted in an urgent need to develop low emissions combustors in order to meet legislative requirements and reduce the impact of civil aviation on the environment. This article provides a comprehensive review of low emissions combustion technologies for modern aero gas turbines. The review considers current high Technologies Readiness Level (TRL) technologies including Rich-Burn Quick-quench Lean-burn (RQL), Double Annular Combustor (DAC), Twin Annular Premixing Swirler combustors (TAPS), Lean Direct Injection (LDI). It further reviews some of the advanced technologies at lower TRL. These include NASA multi-point LDI, Lean Premixed Prevaporised (LPP), Axially Staged Combustors (ASC) and Variable Geometry Combustors (VGC). The focus of review is placed on working principles, a review of the key technologies (includes the key technology features, methods of realising the technology, associated technology advantages and design challenges, progress in development), technology application and emissions mitigation potential. The article concludes the technology review by providing a technology evaluation matrix based on a number of combustion performance criteria including altitude relight auto-ignition flashback, combustion stability, combustion efficiency, pressure loss, size and weight, liner life and exit temperature distribution.

Modelling of heat transfer and fluid flow in the hot section of gas turbines used in power generation: A comprehensive survey

“…According to the US Environmental Protection Agencies (US EPA), 112 there are six identified air pollutants comprised of nitrogen dioxide (NO 2 ), carbon monoxide (CO), sulphur dioxide (SO 2 ), lead (Pb), ozone (O 3 ), and particulates. 113 Generally, the air pollution produced by gas turbines can be divided into three categories: local pollution, cross-border pollution, and global pollution. Local pollution is caused by particulate matter, dust, and heavy metals contained in exhaust gas.…”

Investigation of the Pressure Gain Characteristics and Cycle Performance in Gas Turbines Based on Interstage Bleeding Rotating Detonation Combustion

“…Faced with a greater demand for high efficiency and low pollution, higher level gas turbines have attracted more and more attention in recent years. However, it is quite difficult to improve the cycle efficiency in conventional gas turbines due to the high entropy change during the combustion process [1,2]. In order to break through the bottleneck of efficiency improvement, various advanced combustion technologies, including detonation [3][4][5], wave rotors [6], and shockless explosion [7,8] were studied in the past few decades.…”

Experimental Investigation of Soot Oxidation under Well-Controlled Conditions in a High-Temperature Flow Reactor

“…In technical combustion devices, zones with high oxygen content and already formed soot particles can be identified, so that soot oxidation by molecular oxygen becomes relevant. For example, conventional combustors in aero engines are designed and operated to reduce the formation of NO x (Liu et al, 2017) following the rich-quench-lean (RQL) concept. Three different zones can be identified: (1) A rich-burning zone at the inlet of the combustor, (2) the mixing zone, i.e., a region of rapid quenching by additional air, and (3) the lean-burning zone.…”