- 作者: 洪哲文; 陳德記
- 作者服務機構: 國立清華大學動力機械學系
- 中文摘要: 本篇論文描述由清華大學內燃引擎燃燒實驗室所發展之量測引擎缸內非穩態紊流流場時空特性之軟硬体技術。硬体上,引擎氣缸被改成透明,而一台原二光纖探管之三維雷射測速儀被設計改裝成一兩點同時量測之紊流積分長度尺度量測設備。單點三維量測及雙點單維量測可同時進行。軟体上,循環變異之統計技巧被應用於分析此非穩態紊流流場,其時空特性與物理意義解釋為本論文重點
- 英文摘要: This paper describes hardware and software technology developed at Tsing Hua University to measurethe in-cylinder temporal and spatial characteristics of the turbulent flowfield inside a transparent engine,using a two-probe fiber laser Doppler velocimeter (FLDV). A single-cylinder four-stroke research engine,whose liner is transparent, was operated under 500 rpm motoring conditions. A traverse table was designedwhich combines two fiber optical probes and is capable of both 3-D single-point and I-D two-pointmeasurements of the velocity field. The former measurement was taken to determine the mean flow andturbulence intensity (temporal characteristics) while the latter was employed to determine the integral lengthscales (spatial characteristics) of the turbulent flowfield directly. Statistical algorithms were derived toprocess the random data. The physical meaning of the experimental results is explained.
- 中文關鍵字: fiber laser Doppler velocimeter; turbulence intensity; integral length scales
- 英文關鍵字: --