- 期刊
Studies of Tumbling Motion Generated during Intake in a Bowl-In-Piston Engine
杯狀活塞引擎進氣產生滾轉運動之探討
摘要
最近倡議利用滾轉運動增強引擎中之紊流強度，以增進燃燒效率與降低運轉變異性。本研究之目標即在於研究杯狀活塞柴油機中之滾轉流場結構。爲克服引擎內流場因流速太快而不易實施流場觀到之困難，本研究先依據類比分析的結果，設計並組裝完成一部能模擬杯狀活塞柴油機，但運轉速率較慢之透明水釭類比模擬系統。藉由此透明水缸類比模擬系統之運轉，配合快速攝影系統的使用，成功地達成初步之定性流場觀到結果，進而瞭解滾轉流場之時變性。同時應用高速質點影像測速儀，成功地定量量測瞬時之滾轉流場，證明本引擎類比系統及量到設施之適當性與未來之研究潛能。
關鍵字
無資料並列摘要
Intake-generated tumbling motion has been recently proposed to enhance the turbulence level during compression stroke to promote the combustion rate and reduce operation variations. This study is to investigate the quality of the tumbling motion, especially for the engine with a bowl-in-piston. To overcome the difficulties on the flow visualization caused by the high-speed motion of a real engine, a transparent water-analogy-simulation system is designed based on similarity analysis and fabricated to model the operation of an actual engine. Benchmark tests including the qualitative flow visualization and quantitative full-field measurements using a high-speed PIA system have been conducted to study the time-varying nature of the tumbling motion within the cylinder. The results demonstrate the success on experimental set-ups and the potential of using the current system in studying the complex engine intake-generated tumbling motion.