Effect of Orifice Shape on Flow Behavior and Impingement Heat Transfer

Kanamori, Azusa

doi:10.2174/1877729501103010009

Cited by 12 publications

(4 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The effect of aspect ratio and exit shape have produced similar on-axis switching phenomena. The multiple axes switching phenomena were observed (Kanamori et al 2011) [4]. Gutmark and Grinstein (1999) [5] studied the effect of exit shape, articulating with current ndings.…”

Section: Introductionmentioning

confidence: 72%

Spread Characteristics of Supersonic Noncircular Jets

Kumar¹,

Kumar²,

Mohanta³

2022

Preprint

View full text Add to dashboard Cite

Various research studies on jet spread characteristics have been conducted on the non-circular supersonic jets. However, in these studies, the hydraulic diameter & shape factor of nozzle exit geometry has not been emphasized. The scope of the current investigation includes jet spreading behavior, jet half-width, and axis switching phenomena. This investigation used various types of a nozzle like square, hexagon, elliptical, triangular, circular, and rectangular with divergent and convergent length and throat area ratios are the same. The results ascertained that the hydraulic diameter should be smaller for faster jet mixing. The principal, minor, and diagonal characteristics dimension of hydraulic diameter plays a significant role in spread characteristics. The mixing contribution is lower in circular jets compared to rectangular jets. The distance between the ambient lip and nozzle exit lip plays a vital role at the nozzle exit for mass entertainment.

show abstract

Section: Introductionmentioning

confidence: 72%

Spread Characteristics of Supersonic Noncircular Jets

Kumar¹,

Kumar²,

Mohanta³

2022

Preprint

View full text Add to dashboard Cite

show abstract

“…Watson et al (2003) through experimental observation concluded that fluid leaving a rectangular orifice of a given exit area is more likely to be turbulent than the circular orifice of same exit area even though the peak exit velocities of the both the orifices are the same. The effect of different orifices (circular and regular polygons having 3 to 6 sides) on synthetic jet impingement cooling over a heated plate at different span-wiselocation perpendicular to jet exit direction is studied by Kanamori et al (2011). To achieve heat transfer enhancement using synthetic jet, Chaudhari et al (2010) used circular, square and rectangular shape orifices of same hydraulic diameter with different aspect ratios of rectangular orifice.…”

Section: Orifice Shapementioning

confidence: 99%

Synthetic jet for underwater flow control applications

Kumar¹

2020

Preprint

View full text Add to dashboard Cite

The formation, propagation, and interaction of vortex rings have been the subject of various researchers due to its wide application in nature and day-to-day life. Some of the important applications of vortex rings are volcanic eruption, propulsion of aquatic creatures, sewerage outfalls. As an active device, synthetic jet with a train of large scale coherent structures and zero net mass flow have many practical and industrial applications in flow control.A synthetic jet is generated using a simple cavity with a small orifice at one end and a deformable flexible diaphragm at the opposite end oscillating at different frequency and amplitude. It generates a series of vortex rings due to the changes in the cavity size with diaphragm oscillation. The vortex ring moves away from the orifice exit plane under the influence of self-induced velocity and thus synthesize a jet. Synthetic jet is also called zero net mass flux (ZNMF) system, the net mass transfer through the opening in one cycle is zero but the jet imparts a net transport of momentum to the surroundings.In this work, the aim is to study the characteristics of synthetic jet for various orifice shapes, actuation frequencies and diaphragm displacements. A series of experiments were performed to understand the behavior of circular and rectangular shape synthetic jet in quiescent flow environment. To achieve this, a synthetic jet generation unit mounted on the sidewall of water tank is used. Further, a torpedo shape model with built-in circularsynthetic jet has been designed and developed and the behavior of synthetic jet in crossflow has been investigated. For qualitative study, the bulk flow visualization and laser induced fluorescence (LIF) technique has been used whereas for quantitative measurement, the velocity is measured using hot-film anemometry and Laser Doppler Velocimetry (LDV). Circular orifices of 8, 10 and 13 mm diameter operating at actuation frequencies of 1, 2, 4 and 6 Hz have been used for characterization of circular synthetic jet generation.

show abstract

“…Triangular, square, pentagonal, and hexagonal shapes [26], with this slot jet and circular jets [27] are used regularly. Frequency of jet indicates magnitude of pulsation of jet and such pulsating jets are analyzed [21] [28].…”

Section: Literature Reviewmentioning

confidence: 99%

Cooling Heat Transfer Analysis using Multiple Inline Inclined Air Jet Impingement

Ingole*

2019

IJITEE

View full text Add to dashboard Cite

Air cooling has its own advantages in packaging technology and such many applications. The analysis of multi-jet impingement cooling process is performed. Air is used as fluid in present system. A simulated component with heater plate is cooled with four jets. All jets are placed inline or considered in a row. The jets are inclined to base and reference target to be cooled. The inclination of each jet is changed according to various configurations from 60 and 120 Degree to make packaging as compact as possible. Different configurations are examined and best combination is selected for study of variation of target to jet distance. Interface of flow from one jet with other is creating turbulence and effect of this on cooling target plate is studied experimentally. The graphs are plotted giving variations of Nusselt number as per Reynolds number in laminar range up to 2000. Jet inclination combination with first jet -inside, second jet - outside, third jet - outside, and fourth jet – inside is considered as giving best results with inclinations as 60-120-60- 120 degree respectively. The laminar flow, with jet position inline, in which jet fluid flow lines gets mixed and creating turbulence gives higher average Nusselt number indicating better cooling performance. Further experiments using various fluids and various jet combinations / inclinations may be performed. The correlation is presented showing variation between Nusselt number and Reynolds number for typical case.

show abstract

Effect of Orifice Shape on Flow Behavior and Impingement Heat Transfer

Cited by 12 publications

References 8 publications

Spread Characteristics of Supersonic Noncircular Jets

Spread Characteristics of Supersonic Noncircular Jets

Synthetic jet for underwater flow control applications

Cooling Heat Transfer Analysis using Multiple Inline Inclined Air Jet Impingement

Contact Info

Product

Resources

About