Discharge Coefficient of 3-in-1 Hole with Various Inclination Angle and Hole Pitch
Discharge coefficients of 3-in- 1 hole of three inclination angles and three spacing between holes are presented which described the discharge behavior of a row of holes. The inlet and outlet of the 3-in-1 hole both have a 15° lateral expansion. The flow conditions considered are mainstream turbulence intensities and density ratios of secondary flow to mainstream. The momentum flux ratios varied in the range froom 1 to 4. The comparison is made of the discharge coefficients of three shaped holes to find an optimal hole with low flow loss. The results show that the discharge coefficients of 3-in-1 hole are highest in three shaped holes and therefore this article is focused on the measurements of discharge coefficients of 3-in-1 hole for various geometries and aerodynamic parameters. The measured results of 3-in-1 hole indicate that turbulence intensities, density ratios and momentum flux ratios have weak influence on discharge coefficients for inclination angle of 20°. The high turbulence intensity yields the small discharge coefficients for inclination angle of 45° and 90°.The increased both momentum flux ratios and density ratios lead to the increased discharge coefficients for inclination angle of 45° and 90°. The increased inclination angle causes the rapidly increased discharge coefficients. There is a weak dependence of discharge coefficients on hole pitches.
作 者： Li Guangchao Zhu Huiren Fan Huiming 作者单位： Department of Aeroengines,Northwestern Polytechnical University,Xi'an 710072,China 刊 名： 中国航空学报(英文版) ISTIC 英文刊名： CHINESE JOURNAL OF AERONAUTICS 年，卷(期)： 2008 21(5) 分类号： V2 关键词： aerospace propulsion system gas turbine film cooling hole discharge coefficient