Combustors combustion liners

After combustion, the rich burning mixture leaves the combustion zone and flows between the rows of air jets entering the liner. Each jet entrains air and burning fuel and carries it toward the combustor axis, forming torroidal recirculation patterns around each jet that result in intensive turbulence and mixing throughout the combustor. 

Length. Combustor length must be sufficient to provide for flame stabilization, combustion, and mixing with dilution air. The typical value of the length-to-diameter ratio for liners ranges from three to six. Ratios for casing range from two to four. 

N) E.W. Price, "Recent Advances in Solid Propellant Combustion Instability , Ibid, pp 101-113 O) G.A. Marxman C.E. Wooldridge, "Finite-Amplitude Axial Instability in Solid-Rocket Combustion , Ibid, pp 115-27 P) W.A. Sirignano, "A Theory of Axial-Mode Shock-Wave Oscillations in a Solid-Rocket Combustor ,Ibid, pp 129-37 Q) B.T.Zinn C.T. Saveli, "A Theoretical Study of Three-Dimensional Combustion Instability in Liquid-Propellant Rocket Engines , Ibid, pp 139-47 R) R.J. Priem E.J. Rice, "Combustion Instability with Finite Mach Number Flow and Acoustic Liners , Ibid, pp 149-59 S) M.W. Thring, "Combustion Oscillations in Industrial Combustion Chambers , Ibid, pp 163-68... 

Synthetic liquid fuels derived from coal and shale will differ in some characteristics from conventional fuels derived from petroleum. For example, liquid synfuels are expected to contain significantly higher levels of aromatic hydrocarbons, especially for coal-derived fuels, and higher levels of bound nitrogen. These differences can affect the combustion system accepting such fuels in important ways. In continuous combustors, i.e. gas turbines, the increased aromatics content of coal-derived fuels is expected to promote the formation of soot which, in turn, will increase radiation to the combustor liner, raise liner temperature, and possibly result in shortened service life. Deposit formation and the emission of smoke are other potential effects which are cause for concern. Higher nitrogen levels in synfuels are expected to show up as increased emissions of N0X (NO+NO2) An earlier paper presented results of an experimental study on the effect of aromatics and combustor... 

The smoke point (and Luminometer number with which it can be correlated) is quantitatively related to the potential radiant heat transfer fi-om the combustion products of the fuel. Because radiant heat transfer exerts a strong influence on the metal temperature of combustor liners and other hot section parts of gas turbines, the smoke point provides a basis for correlation of fuel characteristics with the life of these components. 

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