Motion and dispersion of small particles in a turbulent free shear flow and its control

自由剪切湍流中小颗粒的运动和分散及其控制

• 批准号: 02452118
• 负责人: KOSO Toru
• 金额: $ 4.29万
• 依托单位: Kyushu University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1990
• 资助国家: 日本
• 起止时间: 1990 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-02452118/
• 关键词: Particle Motion; Particle Dispersion; Turbulent Jet; Jet Nozzle; Laser Doppler Anemometer; Turbulent Structure; Large Scale Vertex; Plasma Spraying; 噴霧

The motion of small particles in a coflowing turbulent jet is investigated experimentally by means of a laser Doppler anemometer. The air with dilute particles is issued from four different nozzle of which contraction ratio is 1.0, 1.44, 3.24 and 7.84. Average velocity, fluctuation, flow angle and concentration of particles are measured to clarify the effect of nozzle contraction for four different size of particles of 0.8mum DOP aerosols, 32mum glass beads, 58mum glass beads and 100mum glass beads.The results indicate that particle velocity at nozzle exit is changed strongly by nozzle contraction ratio, and this change exerts a marked influence on the velocity and the concentration of larger particles (glass beads) in the jet. The phenomenon that the flow angles of particles in the jet are same for four different nozzle but larger particles have large deflection angle than that of DOP particles is attributed to the large scale vortex structure of the jet.The possibility of the control of particle dispersion by means of particle initial velocity change is also discussed.

通过激光多普勒风速计对同流湍流射流中小颗粒的运动进行了实验研究。含有稀颗粒的空气从四个不同的喷嘴喷出，其收缩比分别为1.0、1.44、3.24和7.84。测量了颗粒的平均速度、波动、流动角和浓度，以阐明喷嘴收缩对0.8mum DOP气溶胶、32mum玻璃珠、58mum玻璃珠和100mum玻璃珠四种不同尺寸颗粒的影响。结果表明，喷嘴收缩比对喷嘴出口处颗粒速度的影响很大，这种变化对速度产生显着影响。 以及喷射中较大颗粒（玻璃珠）的浓度。四种不同喷嘴射流中颗粒的流动角度相同但较大颗粒比DOP颗粒偏转角大的现象归因于射流的大尺度涡流结构。还讨论了通过颗粒初速度变化控制颗粒分散的可能性。

项目成果

T. KOSO et al: "Effect of Nozzle Contraction on the Motion of Small Particles." Trans. JSME. (1992)

T. KOSO 等人：“喷嘴收缩对小颗粒运动的影响”。

高曽 徹: "乱流噴流中の微粒子流動のシミュレ-ション" 日本機械学会論文集B. (1992)

Toru Takaso：“湍流射流中粒子流的模拟”日本机械工程师学会汇刊 B. (1992)

高曽 徹: "乱流噴流中の微粒子の流動・拡散に及ぼすノズル形状の影響" 日本機械学会論文集B. (1991)

Toru Takaso：“喷嘴形状对湍流射流中细颗粒的流动和扩散的影响”日本机械工程师学会汇刊 B. (1991)

T. KOSO et al: "Simulation of particle Motion in a Circular Turbulent Jet" Trans. JSME. (1992)

T. KOSO 等人：“圆形湍流射流中粒子运动的模拟”Trans。

高曽 徹: "円形噴流中の微粒子の流動と拡散" 九州大学機能物質科学研究所報告. 6. (1992)

高曾彻：“圆形射流中细颗粒的流动和扩散”九州大学功能材料科学研究所报告6。（1992）