Afterburner

About: Afterburner is a research topic. Over the lifetime, 811 publications have been published within this topic receiving 5944 citations.

Method and apparatus for determining the thrust of a jet engine

Abstract: Apparatus is known for determining gross thrust in jet engines by measuring various internal pressures, including measurement of total pressure at the nozzle entrance by means of an immersed probe. The immersed probe has a very short life when an afterburner is used in the engine. The apparatus for the invention is able to determine total pressure at the nozzle entrance, without an immersed probe, from the total pressure in the diffuser and the static pressure at the nozzle entrance. Another embodiment makes use of an additional static pressure in the flameholder region. Also, the invention is for determining the gross thrust of an engine and it distinguishes between an engine with a nozzle operating in a choked condition and an unchoked condition.

The Use of an Ultra-Compact Combustor as an Inter-Turbine Burner for Improved Engine Performance

Abstract: : An Inter-Turbine Burner (ITB) represents a novel mechanism for generating additional work from a gas turbine engine in applications where an afterburner would typically be used. An ITB can achieve higher thermal e ciencies over a typical afterburner while also generating shaft work versus only additional thrust. In an e ort to investigate the potential applications for the ITB, a numerical engine cycle comparison was made between the ITB cycle and a conventional afterburning cycle using the Numerical Propulsion System Simulation (NPSS). In the case of thrust augmentation, the ITB model outperformed the afterburning model when Thrust Specific Fuel Consumption (TSFC) is compared to increased thrust, but resulted in decreased fan e ciency and High Pressure Compressor (HPC) stall caused by fan overspeed. In the case of Power Extraction (PX) augmentation the ITB engine achieves similar TSFC results without experiencing component e ciency loss or approaching HPC stall. For the PX augmentation model, the pressure drop across the ITB was varied from 4% to 20%. Large pressure drops were found to increase the TSFC and reduce the HPC stall margin for the ITB model. ITBs are expected to achieve pressure drops between 3% and 5% and for this range the ITB will continue to be more fuel e cient than the afterburning engine model. An experimental investigation was performed focused on integrating the AFIT ITB to accept a common flow source. Three common flow source di users with core to bypass inlet area percentage ratios of 80/20, 70/30, and 60/40 were tested. All three di user designs were found to su er from flow reversal in the bypass stream caused by instances of greater total pressure in the core flow than in the bypass flow. The baseline thrust performance for the JetCat P200 Small Turbine Engine (STE), which will serve as the AFIT ITB vitiated air source, was determined and found to be consistent with manufacturer specifications.

Means and method for reducing differential pressure loading in an augmented gas turbine engine

Abstract: Means and method are disclosed for reducing buckling loads across an afterburner combustion liner in an augmented gas turbine engine. Means for accelerating bypass cooling airflow and then decelerating the accelerated bypass airflow for creating pressure losses to provide reduced-pressure bypass airflow to a plenum surrounding the afterburner liner are disclosed. In a preferred embodiment, the bypass airflow is accelerated to a velocity greater than Mach 1 and is then decelerated to a velocity less than Mach 1 for incurring shock waves for generating pressure losses for reducing differential pressure acting across the liner.

Turbulent bed incinerator for partially dewatered sludge - secondary combustion air injectors inclined adjustably towards afterburner

Abstract: A turbulent bed furnace for incinerating partially de-watered sludge, has a bed formed by a mass of particles of refractory material, maintained in a state of agitation by compressed air fed in from below, which also partially satisfies the combustion requirements, whilst the sludge is injected from above; a combustion zone is provided above the turbulent layer, and larger in section than it; and having a horizontal roof in which a cylindrical afterburning chamber is arranged; has nozzles arranged close to the afterburning chamber inlet for the injection of secondary combustion air. The nozzles are adjustable in their oblique alignment towards the turbulent bed and their tangential direction towards the section of the afterburning chamber inlet. Improved recovery of the heat energy made available. Coarser particles of sludge lifted from the bed, are blown back by the flow from the inclined secondary air nozzles, and burned completely.