Abstract: Impingement heat transfer is one of the useful cooling methods for high temperature gas turbine blades and/or guide vanes in aeroengines.After the cooling jet impinges on the leading edge of the turbine blade and/or guide vane,it flows downstream and turns to be the initial crossflow for the aft row of impinging jet.The process of impingement heat transfer is quite complicated, especially when the target surface is rib roughened.In this paper,Impingement heat transfer from rib roughened surface with two-dimensioned arrays of circular jet with initial crossflow has been investigated experimentally.Through the thousands of experimental data,the effect of the several flow parameters ( Re j=7000～15000,G c/Gj =0～0 5) and geometric parameters ( Xn=5～15,Zn=1 5～5,p/e=5～12,e/d =0 5～1 5) on heat transfer characteristics has been studied.It would be useful for the cooling analysis and design of gas turbine hot section.