JPS5649820A - Gas turbine combustion unit - Google Patents

Abstract

PURPOSE: To restrict a generation of nitroxide by a method wherein a fuel gas is premixed with air before it is fed into a combustion chamber and further a cooling effect caused by a secondary air is improved.

CONSTITUTION: Fuel gases 33a, 33b evaporated in an evaporation and pre-mixing chamber 15 are fed into a head combustion chamber 16 from gas feeding holes 28a, 28b with its smell volume being from the gas feeding hole 28a and a much volume being from the gas feeding hole 28b. Gas flow 33a from the front gas feeding hole 28a increases a concentration of fuel in the head combustion chamber 16 and a flame holding performance is improved by the circulating air flow 34. A part of the gas flow 33b from the rear gas feeding hole 28b is flowed into the circulating flow 34 caused by a circulating flow 30 from the head swirler 29. But almost of it is flowed into the circulation flow 31 applied to the secondary air flow 19 by the swirler for the secondary air in the rear combustion chamber 18. In order to improve a cooling effect caused by the secondary air flow 19 and to keep a better flow holding performance, a diameter d of the head combustion chamber 16 and a position 1 of the gas feeding holes 28a, 28b (axial longitudinal distance from the closed end of the combustion chamber) are defined in a range shown by the two formulas, i.e. 0.2≤1/d≤0.4 and 0.7≤1/d≤0.9.

COPYRIGHT: (C)1981,JPO&Japio