Analysis of Crank Angle-Resolved Vortex Characteristics Under High Swirl Condition in a Spark-Ignition Direct-Injection EngineSource: Journal of Engineering for Gas Turbines and Power:;2018:;volume( 140 ):;issue: 009::page 92807DOI: 10.1115/1.4039082Publisher: The American Society of Mechanical Engineers (ASME)
Abstract: In-cylinder air flow structure makes significant impacts on fuel spray dispersion, fuel mixture formation, and flame propagation in spark ignition direct injection (SIDI) engines. While flow vortices can be observed during the early stage of intake stroke, it is very difficult to clearly identify their transient characteristics because these vortices are of multiple length scales with very different swirl motion strength. In this study, a high-speed time-resolved two-dimensional (2D) particle image velocimetry (PIV) is applied to record the flow structure of in-cylinder flow field along a swirl plane at 30 mm below the injector tip. First, a discretized method using flow field velocity vectors is presented to identify the location, strength, and rotating direction of vortices at different crank angles. The transients of vortex formation and dissipation processes are revealed by tracing the location and motion of the vortex center during the intake and compression strokes. In addition, an analysis method known as the wind-rose diagram, which is implemented for meteorological application, has been adopted to show the velocity direction distributions of 100 consecutive cycles. Results show that there exists more than one vortex center during early intake stroke and their fluctuations between each cycle can be clearly visualized. In summary, this approach provides an effective way to identify the vortex structure and to track the motion of vortex center for both large-scale and small-scale vortices.
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contributor author | Zhao, Fengnian | |
contributor author | Ge, Penghui | |
contributor author | Zhuang, Hanyang | |
contributor author | Hung, David L. S. | |
date accessioned | 2019-02-28T10:58:50Z | |
date available | 2019-02-28T10:58:50Z | |
date copyright | 6/15/2018 12:00:00 AM | |
date issued | 2018 | |
identifier issn | 0742-4795 | |
identifier other | gtp_140_09_092807.pdf | |
identifier uri | http://yetl.yabesh.ir/yetl1/handle/yetl/4251382 | |
description abstract | In-cylinder air flow structure makes significant impacts on fuel spray dispersion, fuel mixture formation, and flame propagation in spark ignition direct injection (SIDI) engines. While flow vortices can be observed during the early stage of intake stroke, it is very difficult to clearly identify their transient characteristics because these vortices are of multiple length scales with very different swirl motion strength. In this study, a high-speed time-resolved two-dimensional (2D) particle image velocimetry (PIV) is applied to record the flow structure of in-cylinder flow field along a swirl plane at 30 mm below the injector tip. First, a discretized method using flow field velocity vectors is presented to identify the location, strength, and rotating direction of vortices at different crank angles. The transients of vortex formation and dissipation processes are revealed by tracing the location and motion of the vortex center during the intake and compression strokes. In addition, an analysis method known as the wind-rose diagram, which is implemented for meteorological application, has been adopted to show the velocity direction distributions of 100 consecutive cycles. Results show that there exists more than one vortex center during early intake stroke and their fluctuations between each cycle can be clearly visualized. In summary, this approach provides an effective way to identify the vortex structure and to track the motion of vortex center for both large-scale and small-scale vortices. | |
publisher | The American Society of Mechanical Engineers (ASME) | |
title | Analysis of Crank Angle-Resolved Vortex Characteristics Under High Swirl Condition in a Spark-Ignition Direct-Injection Engine | |
type | Journal Paper | |
journal volume | 140 | |
journal issue | 9 | |
journal title | Journal of Engineering for Gas Turbines and Power | |
identifier doi | 10.1115/1.4039082 | |
journal fristpage | 92807 | |
journal lastpage | 092807-11 | |
tree | Journal of Engineering for Gas Turbines and Power:;2018:;volume( 140 ):;issue: 009 | |
contenttype | Fulltext |