实验流体力学
實驗流體力學
실험류체역학
JOURNAL OF EXPERIMENTS IN FLUID MECHANICS
2014年
3期
32-38
,共7页
张冬雨%顾蕴松%程克明%郑发明
張鼕雨%顧蘊鬆%程剋明%鄭髮明
장동우%고온송%정극명%정발명
八字形出口%合成射流%边界层%阵列位置%三维机翼%流动控制
八字形齣口%閤成射流%邊界層%陣列位置%三維機翼%流動控製
팔자형출구%합성사류%변계층%진렬위치%삼유궤익%류동공제
splayed-slit%synthetic j et%boundary layer%array location%three-dimensional air-foil%flow control
设计研制了一种适于机翼分离流动控制的八字形出口合成射流激励器,对其出口射流与主流的相互作用特性进行了研究,粒子图像测速仪(PIV)流场测试和边界层速度型测试结果揭示了其控制机制为促进边界层与主流的诱导掺混,提升边界层底层能量。利用该激励器阵列对NACA633-421三维直机翼模型开展了针对射流能量比Cμ和阵列位置两个参数的分离流控制研究,天平测力及翼型表面测压结果显示该激励器可有效抑制翼面流动分离、推迟失速迎角。在设计范围内,射流能量比Cμ值越大,控制效果越好,当Cμ=0.00168时,机翼最大升力系数提升了5.92%,失速迎角推迟了2.5°(激励器阵列位于0.3c处)。激励器阵列的弦向布置位置是一个重要控制参数,阵列位于0.3c处时最大升力系数提升量大于位于0.55c时。
設計研製瞭一種適于機翼分離流動控製的八字形齣口閤成射流激勵器,對其齣口射流與主流的相互作用特性進行瞭研究,粒子圖像測速儀(PIV)流場測試和邊界層速度型測試結果揭示瞭其控製機製為促進邊界層與主流的誘導摻混,提升邊界層底層能量。利用該激勵器陣列對NACA633-421三維直機翼模型開展瞭針對射流能量比Cμ和陣列位置兩箇參數的分離流控製研究,天平測力及翼型錶麵測壓結果顯示該激勵器可有效抑製翼麵流動分離、推遲失速迎角。在設計範圍內,射流能量比Cμ值越大,控製效果越好,噹Cμ=0.00168時,機翼最大升力繫數提升瞭5.92%,失速迎角推遲瞭2.5°(激勵器陣列位于0.3c處)。激勵器陣列的絃嚮佈置位置是一箇重要控製參數,陣列位于0.3c處時最大升力繫數提升量大于位于0.55c時。
설계연제료일충괄우궤익분리류동공제적팔자형출구합성사류격려기,대기출구사류여주류적상호작용특성진행료연구,입자도상측속의(PIV)류장측시화변계층속도형측시결과게시료기공제궤제위촉진변계층여주류적유도참혼,제승변계층저층능량。이용해격려기진렬대NACA633-421삼유직궤익모형개전료침대사류능량비Cμ화진렬위치량개삼수적분리류공제연구,천평측력급익형표면측압결과현시해격려기가유효억제익면류동분리、추지실속영각。재설계범위내,사류능량비Cμ치월대,공제효과월호,당Cμ=0.00168시,궤익최대승력계수제승료5.92%,실속영각추지료2.5°(격려기진렬위우0.3c처)。격려기진렬적현향포치위치시일개중요공제삼수,진렬위우0.3c처시최대승력계수제승량대우위우0.55c시。
A new type of splayed-slit-synthetic-jet-actuator(SSSJA)which is useful for sepa-ration flow control was designed.The core component of the acoustic excitation type actuator was a powerful loudspeaker(4 W).The j et velocity depends on two parameters of excitation frequency and voltage.Particle image velocimetry(PIV)and boundary layer probe was used to study the in-teraction between the jet flow and the main flow.Results revealed that the promotion of both flow dilution and the power of the boundary layer are responsible for the control effect.Flow con-trol on a three-dimensional NACA633-421 airfoil was then conducted to investigate the effect of two parameters of dimensionless energy ratio Cμand the location of the actuator array.Both pres-sure and force measurements data show the ability of SSSJA to reattach the separation flow and to delay the stall at high angles of attack.The control effect gets better along with the larger val-ue of Cμ.At Cμ= 0.00168,maximum of the lift coefficient and the stall angle were increased by 5.92% and 2.5°,respectively.Chordwise location of the actuator array was proved to be a vital parameter in separation flow control.The behavior of the array located at 0.3c is better than the one located at 0.55c.The difference in the control effect is determined by the relative position of the actuator array and the separation point.Experiments were conducted at the wind speed of v∞= 16m/s and the chord-based Reynolds number of Re= 2.7×105 .