RT Journal Article ID 25d646917b7ecedb A1 Lerch, Andreas A1 Schiffer, Heinz-Peter T1 Influence of Internal Cyclone Flow on Adiabatic Film Cooling Effectiveness JF Heat Transfer Research JO HTR YR 2011 FD 2011-02-11 VO 42 IS 2 SP 143 OP 164 K1 turbine blade K1 leading edge K1 ammonia diazo K1 swirl K1 experimental K1 blowing ratio AB The adiabatic film cooling effectiveness on the surface of a symmetrical blade model was measured for eight cylindrical, 59° inclined cooling holes. The holes were fed with different flow types using a cylindrical leading-edge channel. Two configurations were compared: on the one hand, a leading-edge channel flow without swirl (datum configuration), using a sharp-edged inlet; on the other hand, a new cyclone cooling configuration with a positive swirl. The experiments were carried out using the calibrated ammonia diazo technique. The blowing ratios were varied between 0.6 and 1.2, and the film cooling discharge was set to either 20% or 50%. For all these operation points, multiple experiments were conducted and combined using a weighting average method to produce a high full-range resolution. The lateral and area-averaged adiabatic effectiveness is presented up to 45D downstream of the cooling holes. The measurements show a higher area-averaged effectiveness immediately downstream of the cooling holes when using the cyclone cooling configuration. This is due to nonsymmetric flow structures inside the cooling holes. Further downstream, however, it decreases faster. With a low film cooling discharge and rising blowing ratios, these effects are more pronounced. PB Begell House LK https://www.dl.begellhouse.com/journals/46784ef93dddff27,49532fbb633aefa6,25d646917b7ecedb.html