Principles of naval engineering - Historic Naval Ships Association

PRINCIPLES OF NAVAL ENGINEERINGFigure 23-6.— Centrifugal (radial-flow) compressor.147.140efficiency, and good flame stability. Additionalrequirements for the combustion chamber includelow rates of carbon formation, lightweight, reliability, reasonable length of life,and the ability to mix cold air with the hot combustiongases in such a way as to give uniformtemperature distribution to the turbine blades.Only a small part (perhaps one-fourth) ofthe air which enters the combustion chamberarea is burned with the fuel. The remainder ofthe air is used to keep the temperature of thecombustion gases low enough so that the turbinenozzles and blades will not be overheated andthereby damaged.The basic types of combustion chambers incurrent use are the tubular or can-type chamber,the annular chamber, the can-annular chamber,and the elbow chamber.The tubular or can-type chamber, shown infigures 23-7 and 23-8, is used with both axialflowand centrifugal compressors. The can-typecombustion chamber consists of an outer caseor housing within which is a perforated, stainlesssteel, highly heat resistant combustionchamber liner. The combustion chamber housingis divided to facilitate liner replacement. Eachcan-type chamber has its own individual airinlet duct.Interconnector tubes (flame tubes) are a necessarypart of can-type combustion chambers.-TUMWM VKNESrHEAD or LINER-SECONDARY AM147.141Figure 23-7.— Tubular or can-type combustionchamber.600