Performance of primary holes in presence of dilution and cooling holes in a reverse-flow combustor model

Abstract

Experimental investigations on discharge coefficient of row of primary holes of a reverse- flow gas turbine combustor have been carried out using a plane annulus model. The studies have been carried out in a wide range of Reynolds number (0.1 × 10⁴ to 1.65 × 10⁴) on the individual row of primary holes as well as in combination with the other rows of liner holes. It is observed that presence of other rows of liner holes significantly effect static pressure distribution at the primary holes. Static pressure at all the four rows of liner holes, when operating together, increased up to a magnitude till <i>R_e =</i> 1.35×10⁴ and decreased thereafter with further increase in <i>R_e. </i>The values of discharge coefficient of row of primary holes when operating alone remained in the range of 0.74-0.69. These magnitudes reduced in the presence of individual row of dilution (by ≈ 18%) and cooling holes (by ≈6%) while they improved to the extent of ≈0.77 to 0.72 (<i>K= </i>1510 to 1750) when all the four rows operating together.