Mathematical Modelling of a Two Streams Coanda Effect Nozzle

This paper analyses the ACHEON Coanda effect based propulsion nozzle for aircraft propulsion based on the dynamic equilibrium of two jet streams. It presents a large bibliographic analysis and the ACHEON concept and, in particular, the HOMER Nozzle, that is its main component. The Constructal optimization process that allows defining this architecture has presented. A preliminary mathematical model of a 2D case of the system has presented, focusing on the combined effect of the mixing effect of the two streams and the Coanda Effect Adhesion over a convex surface. A CFD preliminary validation has presented in uncompressible regime. The results have been evaluated in 2D cases.

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Theoretical Modeling, Design and Simulation of an Innovative Diverting Valve Based on Coanda Effect

Fluids ◽

10.3390/fluids3040103 ◽

2018 ◽

Vol 3 (4) ◽

pp. 103

Author(s):

Giancarlo Comes ◽

Carlo Cravero

Keyword(s):

Fluid Dynamics ◽

Mathematical Model ◽

Computational Fluid Dynamics ◽

Additive Manufacturing ◽

Water Flow ◽

Coanda Effect ◽

Geometrical Parameters ◽

Convex Wall ◽

Fluidic Device ◽

Coandǎ Effect

The present work is focused on the study of an innovative fluidic device. It consists of a two-ways diverter valve able to elaborate an inlet water flow and divert it through one of the two outlets without moving parts but as a result of a fluctuation of pressure induced by two actuation ports, or channels. Such apparatus is named Attachment Bi-Stable Diverter (ABD) and is able to work with the effect of the fluid adhesion to a convex wall adjacent to it, this phenomenon is known as Coanda Effect; it generates the force responsible for the fluid attachment and the consequent deviation. The main purpose of this work is to develop a knowhow for the design and development of such particular device. A mathematical model for the ABD has been developed and used to find the relationships between the geometrical parameters and the operative conditions. A configuration has been designed, simulated with a computational fluid dynamics approach. A prototype has been printed with and additive manufacturing printer and tested in laboratory to check the effective working point of the device.

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A New Mathematical Model for Coandă Effect Velocity Approximation

INCAS BULLETIN ◽

10.13111/2066-8201.2012.4.4.7 ◽

2012 ◽

Vol 4 (4) ◽

pp. 85-92 ◽

Cited By ~ 4

Author(s):

DRĂGAN Valeriu ◽

Keyword(s):

Mathematical Model ◽

Coanda Effect ◽

Coandǎ Effect ◽

Velocity Approximation

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Mathematical Model of a Constructal Coanda Effect Nozzle

Journal of Applied Fluid Mechanics ◽

10.29252/jafm.09.06.23508 ◽

2016 ◽

Vol 9 (6) ◽

pp. 2813-2822 ◽

Cited By ~ 4

Author(s):

Michele Trancossi ◽

Jill Stewart ◽

Maharshi Subash ◽

Diego Angeli ◽

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...

Keyword(s):

Mathematical Model ◽

Coanda Effect ◽

Coandǎ Effect

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Theoretical and practical aspects of the Coandă effect applied in aeronautics

MATEC Web of Conferences ◽

10.1051/matecconf/201929006003 ◽

2019 ◽

Vol 290 ◽

pp. 06003

Author(s):

Ionică Cîrciu ◽

Constantin Rotaru

Keyword(s):

Flue Gas ◽

Convex Surface ◽

Dynamic Effect ◽

Coanda Effect ◽

Gas Jets ◽

Fluid Jets ◽

Coandǎ Effect ◽

First Time ◽

Airplane Fuselage ◽

Short Flight

The Coandă Effect, or better said, the deviation of fluid jets to stay attached to a convex surface is a complex gas-dynamic effect, named after the Romanian aviation engineer Henri Coandă and it was for the first time highlighted by him in 1910 during the take-off of one of his first planes, Coandă-1910, which was also the first jet plane to fly. During the short flight, Coandă was able to notice the near-fit alignment of the flue gas jets with the airplane fuselage. Later, both Coandă and other scholars have intensively studied the effect that is named The Coandă Effect, in his honor.

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The influence of convective exchanges on Coandã effect

INCAS BULLETIN ◽

10.13111/2066-8201.2019.11.4.17 ◽

2019 ◽

Vol 11 (4) ◽

pp. 191-202 ◽

Cited By ~ 1

Author(s):

Michele TRANCOSSI ◽

Jose PASCOA

Keyword(s):

Heat Exchange ◽

Convective Heat ◽

Convex Surface ◽

Fluid Dynamic ◽

Convective Heat Exchange ◽

Research Direction ◽

Effective Model ◽

Coanda Effect ◽

Cfd Simulations ◽

Coandǎ Effect

Modeling Coandã effect has been a fundamental issue in fluid dynamic research in the XX century. It has lost some interest because of the improvement in CFD, even if it could be still important in the area of the preliminary design of aerodynamic devices that benefits of fluid deflection by convex surfaces. An effective model of Coandã effect has not been defined, and fundamental questions are still open. The influence of convective heat exchange on Coandã adhesion of a fluid stream on a convex surface in the presence of a temperature gradient between the fluid and the convex surface is a problem, which affects many practical cases, but it is still marginally approached by scientific literature. This paper aims to start an effective research direction on the effects of convective heat exchange on Coandã effect. It approaches the problem with a set of CFD simulations. It analyses the previous hypotheses, which are based on Prandtl number and evidences the need of a more effective model that accounts also for the Reynolds number.

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