Study on the effect of the coupling of air supply velocity and air supply inlet size on airflow organization in the tall cooler

This paper investigates the situation of residential kitchen ventilation and individual exposure in China and attempts to reduce the exposure through organizing local make-up airflow. Measurements were conducted in a kitchen chamber to reproduce the real exposure to the cooking-generated particles under the mode of natural make-up airflow surveyed. Measurements results show that an individual cooking in a kitchen could be exposed to a concentration of airborne particles at ∼10 mg/m3 within a simplified cooking process of oil heating, in the case of an experimental kitchen chamber with an open window or closed window/door. Local make-up airflow through upward make-up air supply or downward make-up air supply was further investigated to determine the effectiveness for reduction of the exposure level. When the air-supply velocity at the outlet of the upward make-up air supply or downward make-up air supply mode was well defined, the individual exposure level could be reduced by 2–3 orders of magnitude, as compared to the baseline case when all the make-up air was from open window. Intake fraction of cooking-generated particles could be as low as ∼10−5 and ∼10−6 under the two modes. This finding has illustrated that well-organized local make-up airflow could largely reduce an individual’s exposure to the cooking-generated particles in Chinese residential kitchen.

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Thermal Comfort Study of Wall Hanging Air-Conditioning Office in Summer

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1008-1009.1088 ◽

2014 ◽

Vol 1008-1009 ◽

pp. 1088-1091

Author(s):

Lan Xia Guo ◽

Xiao Yong Peng ◽

Jian Xiang Liu ◽

Xu Sheng Chai ◽

Jing Jing Liang ◽

...

Keyword(s):

Thermal Comfort ◽

Indoor Air ◽

Mean Value ◽

Vital Role ◽

Velocity Fields ◽

Temperature Fields ◽

Air Distribution ◽

Supply Angle ◽

Air Supply ◽

Supply Velocity

Airpak was applied to numerically simulate the air distribution under the same air supply temperature ,different air supply velocity (3.6m/s、2.7m/s and 1.8m/s ) and air supply angle (+15°、-45° and-75°) , and evaluate thermal comfort by Comparative analysis velocity fields, temperature fields, PMV—PPD. The results show that different air supply velocity and air supply angle have a significant impact on indoor air distribution under the same air supply temperature. Air supply angle Plays a vital role in pattern and distribution of indoor flow field,air supply velocity mainly effect the magnitude of indoor velocity and temperature. Synthetically comparied, the model’s best supply parameters are supply velocity 2.7m/s and supply angle75°,which mean value of indoor PMV is-0.09, PPD is 8.5%.

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CFD Study on Effect of the Air Supply Velocity on Contaminant Transport within an Road Vehicle Cabin

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.295-298.532 ◽

2013 ◽

Vol 295-298 ◽

pp. 532-535 ◽

Cited By ~ 1

Author(s):

Li Ping Xiang ◽

Han Qing Wang

Keyword(s):

Transport Model ◽

Co2 Concentration ◽

Air Velocity ◽

Road Vehicle ◽

Velocity Increase ◽

The Road ◽

Vehicle Cabin ◽

Air Supply ◽

Rng Turbulence Model ◽

Supply Velocity

The RNG turbulence model and species transport model were employed to simulate the dispersion of CO2 contaminant in the road vehicle cabin. Three different air supply velocities were analysed, the results indicates that CO2 concentration at middle zone is higher, CO2 concentration at seat zone is higher and easy to gather at lower air velocity. When air velocity is smaller, the height concentration appear distinctly layering. The concentration layering gradually weaken when the air supply velocity increase 5m/s. Increasing the air supply velocity the air velocity is higher than the levels and energy cost.

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Numerical Analysis of Lab Ventilation on Double Gaseous Polluted Sources

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.374-377.475 ◽

2011 ◽

Vol 374-377 ◽

pp. 475-479

Author(s):

Da Hua Jiang ◽

An Gui Li ◽

Fa En Shi ◽

Zhi Hua Wang

Keyword(s):

Numerical Analysis ◽

Dimensional Analysis ◽

Analysis Method ◽

Emission Efficiency ◽

Air Supply ◽

Pollutants Emission ◽

Temperature Efficiency ◽

Dimensional Analysis Method ◽

Supply Velocity

This article uses CFD to study the efficiency of ventilation and pollution discharge of double polluted sources in the lab, and investigate the effect of air exhaust outlet location and air supply velocity on the performance of side ventilation. Using non-dimensional analysis method to analyze change of temperature,velocity with room height, the change of temperature efficiency and pollutants emission efficiency with the air supply velocity. The results show that the efficiencies of temperature and pollutants emission are the highest when h/H=0.175 and v=0.4m/s.

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Variable air supply velocity of forced-air precooling of iceberg lettuces: Optimal cooling strategies

Applied Thermal Engineering ◽

10.1016/j.applthermaleng.2020.116484 ◽

2020 ◽

pp. 116484

Author(s):

Xi-Fang Wang ◽

En-Hai Liu ◽

Zhong-Yang Fan

Keyword(s):

Cooling Strategies ◽

Air Supply ◽

Forced Air ◽

Supply Velocity

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Numerical Simulation on Effects of Air Supply Angle and Air Supply Velocity to Indoor Thermal Environment of Wall Hanging Air-Conditioning

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1030-1032.553 ◽

2014 ◽

Vol 1030-1032 ◽

pp. 553-557

Author(s):

Xiao Yong Peng ◽

Lan Xia Guo ◽

Xu Sheng Chai ◽

Jing Jing Liang ◽

Zhi Qiu Fu

Keyword(s):

Air Conditioning ◽

Thermal Environment ◽

Temperature Fields ◽

Air Distribution ◽

Supply Angle ◽

Air Supply ◽

Supply Condition ◽

Comprehensive Comparison ◽

The One ◽

Supply Velocity

A wall hanging air-conditioning office was simulated on three different air supply angle and three different air supply velocity by the AIRPAK .Based on the velocity fields, temperature fields, PMV-PPD obtained, analysis indoor thermal comfort. The result shows obvious difference of air distribution and great effect of indoor thermal under different air supply angle and different air supply velocity. By comprehensive comparison, the best air supply condition is the one of 75° downward, 3.0m/s.

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Numerical Study of the Respiratory Aerosols Transportation in Ventilated Classroom

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.204-208.4298 ◽

2012 ◽

Vol 204-208 ◽

pp. 4298-4304 ◽

Cited By ~ 2

Author(s):

Guo Hui Feng ◽

Yi Zhang ◽

Xin Ying Lan

Keyword(s):

Respiratory Diseases ◽

Numerical Study ◽

Air Distribution ◽

Ventilation Mode ◽

Displacement Ventilation ◽

Cfd Simulations ◽

Velocity Magnitude ◽

Seating Arrangement ◽

Air Supply ◽

Supply Velocity

Ventilation is important for controlling the airborne transmission of infectious respiratory diseases, particularly in crowed and enclosed spaces, where exist higher risks of cross-infection. This paper studies the spatial concentration distribution and particle tracks of students talking continuously in a classroom with two air distribution methods, including mixing ventilation (MV) and displacement ventilation (DV) using CFD simulations. The classroom is occupied by 10 students with a seating arrangement of 5 rows and 2 columns. The objective of this study is to find out which ventilation mode is more effective in removing respiratory aerosols. The simulation results indicated that the displacement ventilation with the low air supply velocity magnitude and low turbulence could remove the respiratory aerosol droplets and minimize the risk of infectious effectively compared with mixing ventilation.

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Performance of capillary ceiling cooling panel on ceiling surface temperature and indoor thermal environment

Indoor and Built Environment ◽

10.1177/1420326x20917740 ◽

2020 ◽

Vol 29 (6) ◽

pp. 881-894 ◽

Cited By ~ 2

Author(s):

Dong Xie ◽

Chenhua Wang ◽

Chuck Wah Yu ◽

Yun Wang ◽

Hanqing Wang

Keyword(s):

Surface Temperature ◽

Water Temperature ◽

Thermal Environment ◽

Ventilation System ◽

Internal Heat ◽

Experimental Methodology ◽

Maximum Temperature ◽

Air Supply ◽

The Difference ◽

Supply Velocity

A new experimental methodology is presented to show the effect of water supply temperature, mass flow rate and thermal load distribution on the radiant ceiling capacity and thermal comfort conditions. Computerized fluid dynamics simulated vertical temperatures and velocities profiles were validated by a comparison with experimental results and the difference was within 10%. Uniform surface temperature distribution was achieved in a 45.6 m3 test room installed with capillary ceiling radiant cooling panels by an increase in water temperature and air supply velocity. When the ventilation system was turned off, the mean ceiling surface temperature rose from 16.9 ± 0.4°C to 21.5 ± 0.3°C with a rise in the inlet water temperature to 20.1°C. The temperature difference between the head and ankle of an occupant was 2.0°C, which complies with the Chinese standard, GB/T 18049-2017. At a height of 1–1.5 m, the maximum temperature fluctuation was 2°C in the horizontal direction. When the ventilation system was turned on, with the air supply temperature and velocity at 19.8°C and 1.11 m s−1, the ceiling surface temperature was increased by 0.5°C. The indoor air temperature has a positive correlation with the air supply temperature and internal heat load but a negative correlation with air supply velocity.

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