Cyclic Variability in I.C. Engines : Insights from Particle Image Velocimetry Measurements(S.I. Engines, Combustion Diagnostics)

DOI Web Site
  • ELZAHABY A.M.
    Department of Mechanical Power Engineering Faculty of Engineering, Tanta University
  • ELSHENAWY E.A.
    Department of Mechanical Power Engineering Faculty of Engineering, Tanta University
  • GADALLAH A.H.
    Department of Mechanical Power Engineering Faculty of Engineering, Tanta University

抄録

The cycle-to-cycle variation in the flow field inside a four stroke ignition engine has been studied. The particle image velocimetry (PIV) technique has been used to measure the flow field inside the engine. The measurements have been carried out in a motored engine equipped with suitable access. The measurements have been carried out in both the sectional and the planar directions such that the necessary data for calculating the swirl ratio and tumble motions becomes available. The standard deviations from the ensemble averaged measurements for these two motions have been used as indicators for the cyclic variations in the flow field. The effect of the engine speed, inlet valve shrouding and piston geometry on the cyclic variations in the flow has been assessed. According to the analysis of the measurements, it has been found that increasing the engine speed increases both the swirl ratio as well as the cycle-to-cycle variation. The cyclic variability in the swirl ratio decreases when 120° shrouded inlet valve is used. This trend is reverted when the shroud is increased to 180°. Also the cyclic variability in the tumble ratio increases when using the 120° and 180° shrouded inlet valves. The cyclic variability based on the swirl ratio decreases with wider and less deep piston bowel. On the contrary, the cyclic variability in the tumble motion increases with shallow and wider piston bowel. Also the cyclic variability in the swirl ratio increases as the compression ratio increases.

収録刊行物

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ