@techreport{oai:jaxa.repo.nii.ac.jp:00002592, author = {鈴木, 俊介 and 須田, 充 and 松浦, 一哲 and 林, 茂 and Suzuki, Syunsuke and Suda, Mitsuru and Matsuura, Kazuaki and Hayashi, Shigeru}, month = {Feb}, note = {The effects of design parameters and operating conditions on spray characteristics of annular-liquid-film-type airblast atomizers are currently under investigation to obtain insights into the development of high-performance aero-engine fuel injectors. This second report discusses the effects of air swirl, liquid swirl and shape of atomizer exit. A double-air-swirl airblast atomizer designed for research purposes was utilized, whose components were replaceable so that the effects of atomizer design could be easily investigated. The combinations of air swirl directions reported here were limited to "counter-swirl" cases. For quick data acquisitions to cope with many test conditions and atomizer configurations, simple time-average laser sheet imaging and laser diffraction droplet sizing technique were employed for spray evaluation. For fixed air pressure drop and air to fuel mass flow rate ratio, with increasing the outer swirl angle (OSA), the spray angle (SA) increased. For inner swirl angles ISA = -45 and 60 deg., SA showed a rapid increase against OSA after it exceeded a threshold value. The Sauter mean diameter (SMD) decreased with increasing OSA at first, but no further for large OSA values. The SMD increased with increasing OSA afterwards for ISA = -45 and 60 deg., showing its minimum roughly around the threshold value mentioned above, though such tendency was not so clear for ISA = -20 deg. Regarding the effects of liquid swirl direction, the SMD was slightly smaller when its direction was the same as the outer air swirl than the counterpart case. The results on the atomizer attached with a flared outer shroud at its exit are also presented showing the effects of shapes of atomizer exit, which showed a discontinuous increase of the SA for the OSA larger than a critical angle for ISA = -45 deg. This report also includes two appendices, one of which presents the results of some preliminary investigation on the effects of design of annular liquid flow passage, whereas the other contains extensive experimental datasets for various operating conditions for future reconsideration for better understandings., 形態: カラー図版あり, 資料番号: AA0064331000, レポート番号: JAXA-RM-08-015}, title = {液膜式気流噴射弁の設計パラメータ・作動条件が噴霧特性に与える影響: 第二報 気流・液膜の旋回及び噴射弁出口形状の影響}, year = {2009} }