本研究採用渦流法模擬兩相平面噴流場，主要研究目的在於探討外加激擾對粒子擴散之影響。
　　本文首先探討不同雷諾數之單相噴流場特性，模擬結果顯示採用隨機走步式之渦流法可成功模擬出層流與紊流流場之特性，其模擬結果與文獻的實驗數據一致。
　　本研究所使用的激擾方式在於噴口施加縱向激擾波以形成間歇噴流，模擬結果發現此種激擾方式可產生具有空間對稱性之渦偶結構，且於特定激擾頻率可產生leap-frogging現象。此外，可藉由人工調配激擾頻率的大小，控制流場中渦流結構的發展方式，以抑制噴流場偏擺(flapping)現象的發生，在本研究中尤以激擾頻率為0.2之流場具有較佳之代表性。
　　最後於噴口放入不同Stokes number的粒子，研究結果發現粒子的擴散現象深受渦流結構所影響，對於St<<O(1)的粒子而言，本研究所使用的激擾方式無法得到較佳的擴散變異量；St>>O(1)的粒子則可藉由低頻激擾得到較佳的擴散變異量。

　　The evolution of particle-laden plane jet is simulated by the vortex method. The objective of this study is to examine the effects of excitations on particle dispersion in pulsing jet.
　　The various Reynolds number is applied to investigate the evolution of the free jet. The results display the laminar and turbulent flow filed can be simulated by the vortex method with random walk. In addition, the computational results show in good agreement with those of available literatures.
　　The present study uses longitudinal periodic disturbance on the jet exit to form a pulsing jet. The results display spatially symmetric dipole structure can be generated by this forcing type, and the leap-frogging process is achieved successfully by specific forcing frequency. In addition, the flapping phenomenon of the plane jet can be suppressed by this forcing type, and the flow field of forcing frequency fp=0.2 shows better performance.
　　Finally, the study investigates the particle-laden jet by various forcing frequency. Results show that large coherent structure strongly influences the particle dispersion process. For small value of Stokes number, this forcing type scarcely influences particle dispersion process. In contrast, for large value of Stokes number, the particle dispersion process can be modified by this forcing type, and achieved a better dispersion variance using low-frequency forcing.

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