| IMPINGEMENT-INDUCED STABILITY ANALYSIS OF INTAKE MANIFOLD AIR JETS USING HIGH SPEED PIV AND POD |
| Penghui Ge , David Ling-Shun Hung |
| Shanghai Jiao Tong University |
|
|
|
|
|
|
|
| ABSTRACT |
|
The flow stability induced by the impingement of gas jets exiting from the intake manifold affects the in- cylinder flow characteristics of internal combustion engine. Using high-speed planar particle image velocimetry (PIV) with proper orthogonal decomposition (POD) analysis, an investigation was conducted to reveal the spatio-temporal characteristics of annular gas jets impinging in a region between the exits of two intake valves. Unique flow behaviors are identified where strong initial interaction of impinging jets appears near the valve exit as a result of fierce flow vorticity competition in both clockwise and counter-clockwise directions. This mixing zone exhibits strong fluctuations in the angle of the merged gas jet. Flow vorticity and merged jet angle are highly correlated with each other, and the quasi-periodical behavior of the jet impingement is linked to the kinetic energy dissipation. In addition, using POD, the underlying flow structures show large- scale rotating structures with translation which are responsible for the quasi-periodical behavior. In summary, three types of flow stability can be identified resulting from different levels of induced impingement: one-way interaction of single jet flow case, two-way interaction of dual impinging jets with equal flow magnitude, and transitional one-way interaction of dual impinging jets with unequal flow magnitude.
|
| Key Words:
Intake manifold air jets, Stability, Vorticity, Jet direction, Underlying flow structure |
|
|
|
Corresponding Author.
David Ling-Shun Hung , Email. 
Preview
Full text via DOI
Download Citation 
Print 
