Experimental Investigation of Performance and Operating Characterisitics of a Tail-Pipe Burner for a Turbojet Engine

An investigation has been conducted to obtain fundamental information required for the design of a satisfactory tail-pipe burner for augmenting the thrust of turbojet engines. The performance of 10 full-scale tail-pipe burners was investigated on a blower rig and a description and the operating characteristics of each are presented. Investigations were also conducted to determine the combustion and pressure-drop characteristics of the most satisfactory burner, to develop a method of controlling the burner-outlet temperature distribution, and to improve the burner ignition characteristics. A tail-pipe burner was developed that operated satisfactorily over a range of fuel-air ratios with inlet conditions of gas temperature and velocity simulating those in a typical turbojet engine. The average burner-outlet temperature was limited to about 2110 deg F because of the limited air pressure drop available for burning. The performance of a similar tail-pipe burner, which incorporated the principles and design features developed, was investigated concurrently on a full-scale turbojet engine and operated satisfactorily up to nearly stoichiometric fuel-air ratio with an estimated outlet temperature of 3540 deg F.