Abstract
Swirling flow in a motored engine with a bowl-in type piston was measured by Laser Doppler Velocimetry (LDV). Through the detailed measurements at several sections along the cylinder axis, flow characteristics in the piston bowl and squish area were revealed. Rising of swirl level occurs from the upper section near the bowl rim and propagates to the lower part decreasing its rising level. At the rising peak, swirl profile in the bowl shows the solid-body-rotation pattern. On the other hand, swirl in the squish area near TDC decreases rapidly to have a free-vortex-like profile. The analysis on the cycle-resolved velocity data shows that the turbulence intensity in the piston bowl increases slowly before TDC and decays monotonously after a piston passes TDC. Although the periodic oscillation and uneven axial distribution of swirl are detected in the early compression stroke, the angular momentum average over measuring planes decays monotonously and its decaying nature is qualitatively similar to that of an engine with a pancake-type combustion chamber.
| Original language | English |
|---|---|
| Pages (from-to) | 1263-1269 |
| Number of pages | 7 |
| Journal | Transactions of the Japan Society of Mechanical Engineers Series B |
| Volume | 55 |
| Issue number | 512 |
| DOIs | |
| Publication status | Published - Jan 1 1989 |
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All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Mechanical Engineering
Cite this
LDV Measurements of Axial Distributions of In-Cylinder Gas Velocities : (A Case of an Engine with a Bowl-in Type Piston). / Kido, Hiroyuki; Tajima, Hiroshi; Fujita, Kazuto.
In: Transactions of the Japan Society of Mechanical Engineers Series B, Vol. 55, No. 512, 01.01.1989, p. 1263-1269.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - LDV Measurements of Axial Distributions of In-Cylinder Gas Velocities
T2 - (A Case of an Engine with a Bowl-in Type Piston)
AU - Kido, Hiroyuki
AU - Tajima, Hiroshi
AU - Fujita, Kazuto
PY - 1989/1/1
Y1 - 1989/1/1
N2 - Swirling flow in a motored engine with a bowl-in type piston was measured by Laser Doppler Velocimetry (LDV). Through the detailed measurements at several sections along the cylinder axis, flow characteristics in the piston bowl and squish area were revealed. Rising of swirl level occurs from the upper section near the bowl rim and propagates to the lower part decreasing its rising level. At the rising peak, swirl profile in the bowl shows the solid-body-rotation pattern. On the other hand, swirl in the squish area near TDC decreases rapidly to have a free-vortex-like profile. The analysis on the cycle-resolved velocity data shows that the turbulence intensity in the piston bowl increases slowly before TDC and decays monotonously after a piston passes TDC. Although the periodic oscillation and uneven axial distribution of swirl are detected in the early compression stroke, the angular momentum average over measuring planes decays monotonously and its decaying nature is qualitatively similar to that of an engine with a pancake-type combustion chamber.
AB - Swirling flow in a motored engine with a bowl-in type piston was measured by Laser Doppler Velocimetry (LDV). Through the detailed measurements at several sections along the cylinder axis, flow characteristics in the piston bowl and squish area were revealed. Rising of swirl level occurs from the upper section near the bowl rim and propagates to the lower part decreasing its rising level. At the rising peak, swirl profile in the bowl shows the solid-body-rotation pattern. On the other hand, swirl in the squish area near TDC decreases rapidly to have a free-vortex-like profile. The analysis on the cycle-resolved velocity data shows that the turbulence intensity in the piston bowl increases slowly before TDC and decays monotonously after a piston passes TDC. Although the periodic oscillation and uneven axial distribution of swirl are detected in the early compression stroke, the angular momentum average over measuring planes decays monotonously and its decaying nature is qualitatively similar to that of an engine with a pancake-type combustion chamber.
UR - http://www.scopus.com/inward/record.url?scp=0024645560&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0024645560&partnerID=8YFLogxK
U2 - 10.1299/kikaib.55.1263
DO - 10.1299/kikaib.55.1263
M3 - Article
AN - SCOPUS:0024645560
VL - 55
SP - 1263
EP - 1269
JO - Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B
JF - Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B
SN - 0387-5016
IS - 512
ER -