Thermal Air Flow Analysis of an Automotive Headlamp - The PIV Measurement and the CFD Simulation by Using a Skeleton Model

Microbubble generators are of considerable importance to a range of scientific fields from use in aquaculture and engineering to medical applications. This is due to the fact the amount of sea life in the water is proportional to the amount of oxygen in it. In this paper, experimental measurements and computational Fluid Dynamics (CFD) simulation are performed for three water flow rates and three with three different air flow rates. The experimental data presented in the paper are used to validate the CFD model. Then, the CFD model is used to study the effect of diverging angle and throat length/throat diameter ratio on the size of the microbubble produced by the Venturi-type microbubble generator. The experimental results showed that increasing water flow rate and reducing the air flow rate produces smaller microbubbles. The prediction from the CFD results indicated that throat length/throat diameter ratio and diffuser divergent angle have a small effect on bubble diameter distribution and average bubble diameter for the range of the throat water velocities used in this study.

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Indoor air flow analysis based on lattice Boltzmann methods

Energy and Buildings ◽

10.1016/s0378-7788(02)00069-5 ◽

2002 ◽

Vol 34 (9) ◽

pp. 941-949 ◽

Cited By ~ 20

Author(s):

B Crouse ◽

M Krafczyk ◽

S Kühner ◽

E Rank ◽

C van Treeck

Keyword(s):

Indoor Air ◽

Lattice Boltzmann ◽

Air Flow ◽

Flow Analysis ◽

Lattice Boltzmann Methods ◽

Indoor Air Flow

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Measurement and Calculation of Ventilation in the Floor of the Brewery Žirovnice

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1041.321 ◽

2014 ◽

Vol 1041 ◽

pp. 321-324

Author(s):

Jiří Jurka ◽

Jan Škramlík

Keyword(s):

Air Flow ◽

Flow Analysis ◽

Experimental Measurements ◽

Historic Buildings ◽

The City ◽

Cultural Monuments

The article discusses how to test the functionality of air insulations designed for the floor ventilation in historic buildings and follows on from the previously published articles. A flow analysis is being performed on an object of the City of Zirovnice which has been registered in the list of cultural monuments and was built as a brewery in the years 1589-1592 on the site of an older medieval building. The foundations and external brickwork consist mostly of stone. This article brings new air flow readings. The aim of the article is to analyse in detail the air flow in a specific floor void with the aid of modern CFD programs and experimental measurements using the ALMEMO device.

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Calculated research of aeroelastic stability of a bridge over the river Ob in Salekhard at the stage of assembling and operation

Russian journal of transport engineering ◽

10.15862/13sats319 ◽

2019 ◽

Vol 6 (3) ◽

Author(s):

Anastasiya Shustikova ◽

Andrei Kozichev ◽

Sergei Paryshev ◽

Konstantin Strelkov

Keyword(s):

Cfd Simulation ◽

Load Capacity ◽

Air Flow ◽

Lift Coefficient ◽

High Strength ◽

Railway Bridge ◽

Aeroelastic Stability ◽

Ansys Fluent ◽

Long Span ◽

Long Span Bridge

Recently, long span bridge construction has been demanded for development of the regions of the Russian Federation. In terms of economy, it’s useful to build a combined road-railway bridge. Such bridges, generally, constitute a metal cross-cutting girder with carriageways on lower, upper or both zones of the girder. The major advantages of combined bridges are high strength and load capacity, plus cross-cutting to wind load. Focus of this research is a combined road-railway bridge over the Ob river at the stage of assembling and operation. The purpose of the study was to determine the limits of aeroelastic stability of combined road-railway bridge at the stage of assembling and operation using numerical simulation. To better understand the bridges behaviour in air flow, flow around a section model has been researched with CFD simulation in the ANSYS FLUENT. Then based on the given results of the calculations the dependence of the bridge vibrations on wind speed within a specified range is obtained, and also values of drag coefficient Сх, lift coefficient Су and torque coefficient Мz are received. These studies were carried out in the range of angles of attack α = ±3°. The possibility of divergence and galloping was also estimated. The results of the study made it possible to estimate the influence of air flow on combined bridge cross-cutting girder. Overall, the conducted research seems promising for further investigation and development in the field of bridge aeroelasticity.

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Air Flow Analysis in Square Duct Bend

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.695.622 ◽

2014 ◽

Vol 695 ◽

pp. 622-626 ◽

Cited By ~ 1

Author(s):

Mohamad Nor Musa ◽

Mohd Nurul Hafiz Mukhtar

Keyword(s):

Reynolds Number ◽

Pressure Drop ◽

Cross Section ◽

Air Flow ◽

Flow Analysis ◽

Maximum Velocity ◽

Maximum Pressure ◽

Air Velocity ◽

Square Duct ◽

Inlet Velocity

This paper present new result for experimental analysis of air flow velocity and pressure distributions between two ducts bend: (1) 90° duct bend with a single turning vane having 0.03m radius and (2) 90° duct bend with double turning vane, in 0.06 × 0.06 m duct cross section. The experiment used five different Reynolds numbers chosen between the ranges 1 ×104 and 6×104. Each experiment has four point measurements: (1) point 1 and point 2 at cross section A-A and (2) point 3 and point 4 at cross section B-B. The first experimental study used single turning vane radius 0.03m with inlet air velocity from 2.5m/s to 12.2m/s. And for the second experiment that used square turning vane with 0.03m radius. In experiment 2, the inlet air velocity also start from 2.5m/s to 12.2m/s. From analysis results, the pressure drop in experiment 1 is higher than experiment 2. As example the maximum pressure drop at 7.5m/s inlet air velocity between point 1 and 3 was found to be 71.6203 Pa in experiment 1 as compared to 61.8093 Pa in experiment 2. The velocity after duct bend is greater when using double turning vane compare used single turning vane as maximum velocity at point 3 in experiment 2 compare to velocity at point 3 in experiment 1 that is 55.677× 10-4 m/s and 54.221× 10-4 m/s. The velocity at duct wall is equal to zero. When increase the value of Reynolds number or inlet velocity, the maximum velocity and total pressure also increase. For example in experiment 1 at point 1, the velocity is 48.785 × 10-4 m/s at Reynolds number 1 ×104 and velocity 65.115×10-4 m/s at Reynolds number 12.2 ×104 . Velocity flow in duct section are lower than inlet velocity. In experiment 1, the inlet velocity is 2.5m/s meanwhile the maximum velocity in the duct section at point 2 is 73.075×10-4 m/s that is much more lower than inlet velocity.

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