Outlets Airflow Velocity Enhancement of an Automotive HVAC Duct

The purpose of this work is to determine the drag characteristics and the torque of three C-section blades wind car. Three C-section blades are directly connected to wheels by using of various kinds of links. Gears are used to convert the wind energy to mechanical energy to overcome the load exercised on the main shaft under low speed. Previous work on three vertical blades wind car resulted in discrepancies when compared to this work. Investigating these differences was the motivation for this series of work. The calculated values were compared to the data of three vertical blades wind car. The work was conducted in a low wind speed. The drag force acting on each model was calculated with an airflow velocity of 4 m/s and angular velocity of the blade of 13.056 rad/s.

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Experiment and numerical modeling of asymmetrically initiated hexagonal prism warhead

Advances in Mechanical Engineering ◽

10.1177/1687814016687966 ◽

2017 ◽

Vol 9 (1) ◽

pp. 168781401668796 ◽

Cited By ~ 1

Author(s):

Yuan Li ◽

Yuquan Wen

Keyword(s):

Numerical Modeling ◽

The Other ◽

Energy Utilization ◽

Hexagonal Prism ◽

Cylindrical Structure ◽

Damage Probability ◽

Other Hand ◽

Density Enhancement ◽

Fragment Distribution ◽

Velocity Enhancement

Traditional fragmentation warheads are usually initiated on the axis, producing a uniform fragment distribution around the warhead, but only little portion of them can be imposed on the targets. The aimable warhead, on the other hand, using the off-axis initiations or the structure deforming, can improve the warhead energy utilization highly. Seeking methods to both enhance the fragment velocity and density has significant value for improving the target damage probability. In this article, a warhead shaped as hexagonal prism was studied using arena experiment and numerical modeling and compared with the traditional cylindrical structure. The fragment velocities and target hit patterns of the two types of warheads under axial initiation and asymmetrical initiation are obtained. It is revealed that for the hexagonal prism warhead, the asymmetrical initiation can enhance the fragment velocities by 27.71% and enhance fragment density by 34.09% compared to the axial initiation. The fragment velocity enhancement is close to that of the cylindrical warhead, but the fragment density enhancement is far above the cylindrical warhead. This indicates that the asymmetrically initiated hexagonal prism warhead is a very effective aimable warhead.

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Aerosol Collection Efficiency of a Graded Metal-Fiber Filter at High Airflow Velocity (10 m s–1)

Aerosol Science and Technology ◽

10.1080/02786826.2010.537399 ◽

2011 ◽

Vol 45 (3) ◽

pp. 336-342 ◽

Cited By ~ 8

Author(s):

George A. Klouda ◽

Robert A. Fletcher ◽

J. Greg Gillen ◽

Jennifer R. Verkouteren

Keyword(s):

Collection Efficiency ◽

Metal Fiber ◽

Airflow Velocity ◽

Fiber Filter

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Ventilation Characteristics of Modeled Compact Car Part 1 Airflow Velocity Measurement with PIV

SAE International Journal of Passenger Cars - Mechanical Systems ◽

10.4271/2008-01-0732 ◽

2008 ◽

Vol 1 (1) ◽

pp. 631-639 ◽

Cited By ~ 5

Author(s):

Yoshiichi Ozeki ◽

Jeong-Hoon Yang ◽

Hideaki Nagano ◽

Shinsuke Kato ◽

Eiji Nomura ◽

...

Keyword(s):

Velocity Measurement ◽

Airflow Velocity

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Simulation and Comparative Analysis on Environmental Control in Subway

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.209-211.1068 ◽

2012 ◽

Vol 209-211 ◽

pp. 1068-1072

Author(s):

Ming Liu ◽

Bao Gang Zhang ◽

Liu Wen ◽

Zhong Zhi Huang

Keyword(s):

Temperature Field ◽

Energy Consumption ◽

Comparative Analysis ◽

Environmental Control ◽

Thermal Environment ◽

Airflow Velocity ◽

Waiting Room ◽

Local Climate ◽

Average Temperature ◽

Environment Control

To ensure passengers can have a comfortable thermal environment in the subway waiting room is one of the main targets in subway environment control. By using the CFD software, this paper takes an island platform with double-layer of Shenyang as the object to simulate the thermal environment of platform screen door and ventilation in the open system, then detailed analysis on the variation of the temperature field, airflow velocity field in the typical position. The results indicated that average temperature of no-PSD system platform is 2.5 ~3 °C higher than that of PSD system, standing room is 1.5 °C higher than that of PSD system , but these also meet the requirement of the standards of the environmental control and passengers’ thermal comfort. Meanwhile, through the comparative analysis to the energy consumption of the two systems, we find ventilating condition has superior to PSD system in energy saving, and it is more suitable for the local climate in the northeast.

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Saccade–Vergence Interactions in Macaques. I. Test of the Omnipause Multiply Model

Journal of Neurophysiology ◽

10.1152/jn.01336.2004 ◽

2005 ◽

Vol 94 (4) ◽

pp. 2295-2311 ◽

Cited By ~ 23

Author(s):

C. Busettini ◽

L. E. Mays

Keyword(s):

Eye Movements ◽

Main Sequence ◽

Peak Velocity ◽

Alternative Models ◽

Omnipause Neurons ◽

Velocity Enhancement

Horizontal vergence eye movements are movements in opposite directions used to change fixation between far and near targets. The occurrence of a saccade during vergence causes vergence velocity to be transiently enhanced. The goal of this study was to test in the monkey the previously described Multiply Model (Zee et al. 1992) that holds that, in humans, the speeding of vergence during a saccade may be the result of the disinhibition of a subgroup of vergence-related neurons by the saccadic omnipause neurons (OPNs). In agreement with the Multiply Model: 1) the onset of the enhancement was closely related to saccadic onset, and thus linked to the onset of the OPN pause; 2) the magnitude of the vergence velocity enhancement was strongly dependent on saccade–vergence timing. Contrary to the Multiply Model: 1) the peak of the vergence velocity enhancement was dependent on saccadic peak velocity; 2) the dependency on saccadic peak velocity was not the indirect result of a dependency on saccadic duration and therefore on the duration of the OPN pause; 3) the decline of the vergence enhancement, identified by the time of the peak of the enhancement velocity, occurred too early to be linked to the end of the OPN pause; 4) vergence enhancement had a saccadic-like peak-velocity/size main sequence. Overall, the evidence is incompatible with the OPN Multiply hypothesis of vergence enhancement. Alternative models are described in an accompanying paper.

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Effect of microclimate on the airborne dust and endotoxin concentration in a broiler house

Czech Journal of Animal Science ◽

10.17221/329-cjas ◽

2008 ◽

Vol 53 (No. 2) ◽

pp. 83-89 ◽

Cited By ~ 19

Author(s):

M. Vučemilo ◽

K. Matković ◽

B. Vinković ◽

J. Macan ◽

V.M. Varnai ◽

...

Keyword(s):

Relative Humidity ◽

Measured Temperature ◽

Air Concentration ◽

Airflow Velocity ◽

Poultry House ◽

Airborne Dust ◽

Endotoxin Concentration ◽

Fattening Period ◽

Broiler House ◽

Poultry Farming

Poultry farming is considered to be a notable source of bioaerosols. They can be a risk factor from the aspect of some diseases and for the environment. A study was conducted to assess the effect of microclimate on the level of airborne dust and endotoxins in an intensive broiler fattening facility. The content of airborne dust, endotoxins, air temperature, relative humidity, airflow velocity, ammonia and carbon dioxide were determined. The study was conducted in a poultry house accommodating 22 000 broilers of Ross-308 breed. The measured temperature in the broiler house ranged from 22.02°C to 31.05°C, relative humidity from 49.55% to 65.45%, and airflow velocity from 0.07 m/s to 0.09 m/s. The air concentration of dust ranged from 2.0 mg/m3 at the end of fattening period to 4.9 mg/m3 in the mid-fattening period, and endotoxins from 6.21 EU/m3 in the second study week to 99.40 EU/m3 at the end of fattening period. The air concentration of ammonia ranged from 5.17 ppm at the beginning to 25.49 ppm at the end of fattening period. Air concentrations of dust and endotoxins recorded in this poultry house varied during the fattening period and depended on relative humidity and temperature as demonstrated by multiple regression at the level of P ≤ 0.05.

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