空气动力学学报
空氣動力學學報
공기동역학학보
ACTA AERODYNAMICA SINICA
2010年
2期
226-233
,共8页
简化液滴%气动力%两相流%阻力系数
簡化液滴%氣動力%兩相流%阻力繫數
간화액적%기동력%량상류%조력계수
simplified droplet%aerodynamic force%two phase flow%drag coefficient
从研究超声速气流中简化液滴(刚性小球)的气动力着手,比较分析使用CFD方法与使用两相流理论中已有的颗粒阻力系数模型得到的简化液滴气动力结果,得出Charles B.Henderson给出的阻力系数经验关系式适用于计算简化液滴在超声速气流中的运动.进一步,对不同直径简化液滴的运动开展工程方法的计算.在来流Ma=2.7的二维平板超声速流场中选取一个截面,作为气相流场,结果显示:(1)简化液滴与主气流存在相对超声速运动,当简化液滴直径d_k≤0.12mm时,纵向相对超声速运动区域约为0.15m~0.4m,当d_k>0.12mm时,作用区域明显增大;(2)以10m/s喷射出的简化液滴,其横向穿透深度与纵向运动距离比约为0.004m/1m~0.021m/1m;(3)以100m/s的速度喷射出的30~120μm直径简化液滴,其横向穿透深度与纵向运动距离比约为0.02m/1m~0.055m/1m,实际过程中,小尺寸简化液滴的汽化很快,其穿透深度很小.
從研究超聲速氣流中簡化液滴(剛性小毬)的氣動力著手,比較分析使用CFD方法與使用兩相流理論中已有的顆粒阻力繫數模型得到的簡化液滴氣動力結果,得齣Charles B.Henderson給齣的阻力繫數經驗關繫式適用于計算簡化液滴在超聲速氣流中的運動.進一步,對不同直徑簡化液滴的運動開展工程方法的計算.在來流Ma=2.7的二維平闆超聲速流場中選取一箇截麵,作為氣相流場,結果顯示:(1)簡化液滴與主氣流存在相對超聲速運動,噹簡化液滴直徑d_k≤0.12mm時,縱嚮相對超聲速運動區域約為0.15m~0.4m,噹d_k>0.12mm時,作用區域明顯增大;(2)以10m/s噴射齣的簡化液滴,其橫嚮穿透深度與縱嚮運動距離比約為0.004m/1m~0.021m/1m;(3)以100m/s的速度噴射齣的30~120μm直徑簡化液滴,其橫嚮穿透深度與縱嚮運動距離比約為0.02m/1m~0.055m/1m,實際過程中,小呎吋簡化液滴的汽化很快,其穿透深度很小.
종연구초성속기류중간화액적(강성소구)적기동력착수,비교분석사용CFD방법여사용량상류이론중이유적과립조력계수모형득도적간화액적기동력결과,득출Charles B.Henderson급출적조력계수경험관계식괄용우계산간화액적재초성속기류중적운동.진일보,대불동직경간화액적적운동개전공정방법적계산.재래류Ma=2.7적이유평판초성속류장중선취일개절면,작위기상류장,결과현시:(1)간화액적여주기류존재상대초성속운동,당간화액적직경d_k≤0.12mm시,종향상대초성속운동구역약위0.15m~0.4m,당d_k>0.12mm시,작용구역명현증대;(2)이10m/s분사출적간화액적,기횡향천투심도여종향운동거리비약위0.004m/1m~0.021m/1m;(3)이100m/s적속도분사출적30~120μm직경간화액적,기횡향천투심도여종향운동거리비약위0.02m/1m~0.055m/1m,실제과정중,소척촌간화액적적기화흔쾌,기천투심도흔소.
Beginning from the study for the aerodynamic force on simplified droplet (little rigid sphere) in supersonic flow, the results of aerodynamic force, using by CFD method and by the drag coefficient models in the two phase flow theory, are compared and analyzed.So it is concluded that the drag coefficient formula given by Charles B.Henderson is suitable to simulate the simplified droplet movement in supersonic airflow.Further more, the calculation of different diameter simplified droplet movement is carried out by using engi-neering calculation method.One section of two dimensional supersonic flat flow with Ma2.7 inflow is chosen as gas flow field and the results show that, (1) there exits relative supersonic movement between the simpli-fied droplet and the main gas flow, the lengthways movement distance of which is about 0.15~0.4m for the simplified droplets with d_k≤0.12mm diameters and increases obviously for those with d_k>0.12mm diame-ters, (2) for the simplified droplets injected with 10m/s velocity the ratios of the transverse penetration deepness to the lengthways movement distance are about 0.004m/1m~0.021m/1m, (3) for the 30μm~120μm simplified droplets injected with 100m/s velocity the ratios of the transverse penetration deepness to the lengthways movement distance are about 0.02m/1m~0.055m/1m.In the actual process the evaporation of little size simplified droplet is fast and its penetration deepness is short.