The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 26, 1983
Filed:
Jun. 15, 1981
Richard C Adkins, Milton Keynes, GB;
Rolls-Royce Limited, London, GB;
Abstract
A combustion chamber of a gas turbine engine has an upstream variable rate diffuser for controlling the airflow into first and second annular ducts which partially surround the combustion chamber, primary and dilution air flowing into the combustion chamber from the first annular duct and bypass air flowing into the combustion chamber from the second annular duct. The variable rate diffuser comprises a primary duct and downstream fence located in a secondary duct which has a bleed duct with a variable bleed rate, the outlet of the primary duct being smaller in diameter than the inlet to the first annular duct. In operation, by varying the bleed rate, the rate of diffusion into the combustion chamber can be varied, and if the bleed rate is reduced to low bleed conditions at high power conditions or to zero bleed condition at full power condition, vitiated air can be drawn from the combustion chamber and flowed in a reverse direction, upstream along the second annular duct and returned to the combustion chamber at its upstream end whereby the rate of combustion is reduced thereby reducing emissions of NO.sub.x.