Numerical Simulation on Mechanical Ventilation for Odor Removal Efficiency in a Bathroom

2011 ◽  
Vol 243-249 ◽  
pp. 4877-4882
Author(s):  
Yiin Kuen Fuh ◽  
Wei Chi Huang
Keyword(s):  
Numerical Simulation ◽  
Mechanical Ventilation ◽  
Removal Efficiency ◽  
Previous Experiment ◽  
Change Rate ◽  
Air Change Rate ◽  
Odor Removal ◽  
Simulation Results ◽  
Ventilation Rates ◽  
Air Vent

This paper numerically studies the effect of ventilation rates and bathroom equipment locations on the odor removal efficiency in a modeled bathroom. Simulation results agree well with previously published experiments such that moving exhaust air vent from ceiling to wall and addition of one supply fan would significantly improve odor removal efficiency. In addition, by doubling the area of exhaust vent under a fixed air change rate, odor removal efficiency (ORE) can be greatly enhanced to 16-30% while previous experiment showed only a moderate 4% increase in ORE when doubled the flow rate of supply air.

The Effect of Air Change Rate and Cleanroom Garment on Cleanliness in Grade B Cleanroom

2013 ◽  
Vol 441 ◽  
pp. 514-517
Author(s):  
Hao Li ◽  
Zhi Jun Zou ◽  
Fei Wang
Keyword(s):  
Numerical Simulation ◽  
Human Body ◽  
Operating Cost ◽  
Change Rate ◽  
Air Change Rate

The air change rate and cleanroom garment have a great impact on cleanliness and operating cost of cleanroom. This paper use the method of numerical simulation to research the effect on cleanliness with different air change rate and cleanroom garment in Grade B cleanroom. The results show the air change rate of 20/h will meet the requirements of the specification and the garment cover whole human body will decrease the particles emitted from human body mostly.

scholarly journals The effect of cyclical stimulation on the primary neurons of Bombyx Mori

2018 ◽  
Author(s):  
Yeti Zuko ◽  
Kazuo Maeda
Keyword(s):  
Numerical Simulation ◽  
Water Potential ◽  
Bombyx Mori ◽  
Low Voltage ◽  
Primary Neurons ◽  
Change Rate ◽  
Silk Production ◽  
Simulation Results ◽  
Free Media ◽  
And Storage

Changes to the Silkworm axon initiation segment in frequently firing neurons are known to be important predictors of silk production in the Japanese Silkworm (Bombyx Mori). Studying this phenomenon in primary neurons is critical to understanding the regulation of silk production. To study these changes we used cyclical stimulations using micro-electrodes to the Silkworm axon initiation segment of primary neurons. Numerical simulation results indicate that Silkworm axon initiation segment water potential fluctuated sinusoidally on high voltage only. Fluctuations in the amplitude and trend were caused by calcium flow and storage resistance, respectively. The change in Silkworm axon initiation segment-stored water was proportional to the change rate in water potential. Silkworm axon initiation segment diameter increased with fluctuations in calcium free media; moreover, it varied slightly under low voltage conditions. Our results indicate that the changes in Silkworm axon initiation segment diameter were caused by changes in water potential, which can be attributed to subcellular gated calcium channels within the primary neurons.

scholarly journals A Discussion Regarding the Measurement of Ventilation Rates Using Tracer Gas and Decay Technique

2020 ◽  
Vol 5 (10) ◽  
pp. 85
Author(s):  
Ricardo M. S. F. Almeida ◽  
Eva Barreira ◽  
Pedro Moreira
Keyword(s):  
Cross Contamination ◽  
Single Family ◽  
Outdoor Temperature ◽  
Time Dependency ◽  
Tracer Gas ◽  
Large Variability ◽  
Change Rate ◽  
Air Change Rate ◽  
Ventilation Rates

The measurement of ventilation rates is crucial in understanding buildings’ performances, but can be a rather complex task due to the time-dependency of wind and buoyancy forces, which are responsible for the pressure differences that induce air movement across the envelope. Thus, assessing air change rate through one-time measurements during brief periods of time may not be a reliable indicator. In this paper, the variability in the measurement of ventilation rates using the decay technique was evaluated. To that end, two compartments of a typical single-family detached dwelling were selected as a case study and 132 tests were performed, considering two different boundary conditions (door closed and door open). This work allowed the large variability of the results to be highlighted, as the coefficient of variation ranged from 20% to 64%. Wind speed had a key effect on the results, especially because during the measurements indoor–outdoor temperature differences were not so significant. The possibility of using occupant-generated carbon dioxide as tracer gas was also analyzed, but problems of cross-contamination were identified.

The Minimum Ventilation Intensity Research Using Selected Parameters

2013 ◽  
Vol 353-356 ◽  
pp. 3029-3033
Author(s):  
Richard Nagy ◽  
Danica Košičanová
Keyword(s):  
Ventilation System ◽  
Ventilation Rate ◽  
Cfd Simulations ◽  
Change Rate ◽  
Air Change Rate ◽  
Distribution Scheme ◽  
Air Ventilation ◽  
Ventilation Rates ◽  
The Impact ◽  
Selection Of

The air ventilation rates defined in Standard STN EN 15 251:2007 present air change rate in which the objective benefit of proper selection of ventilation system and air distribution scheme is lost (erased) in relation to IAQ [1,2]. With help of sensory evaluation in research the total minimum ventilation rate was estimated. It was reason how to determine major boundary condition (air quantity = air ventilation rate) for minimizing of responsibility size of air quantity (quantitative component of ventilation) and maximize the impact of the choice of distribution scheme and the distribution element (qualitative component of ventilation) for transfer and distribution of pollutants in research. The total air ventilation rate for next experimental measurements was established as the intersection of three air ventilation rates according to research harmonogram. This air ventilation rate was necessary to supply to occupant to experimental classroom and also as input value to CFD simulations.

Design and Simulation Research on Mechanical Ventilation System for Small Underground Granary

2014 ◽  
Vol 875-877 ◽  
pp. 2148-2151
Author(s):  
Hai Hong Zhang ◽  
Zhong Ying Wang ◽  
Qiang Liu ◽  
Peng Fei Ma
Keyword(s):  
Numerical Simulation ◽  
Mechanical Ventilation ◽  
Pressure Field ◽  
Ventilation System ◽  
Simulation Research ◽  
New Type ◽  
Simulation Results ◽  
Dynamic Numerical Simulation ◽  
Set Up ◽  
Better Than

The mechanical ventilation system of new type underground granary was designed and three wind pipe models with different length were investigated in this paper. Dynamic numerical simulation was applied for evaluating the cooling effect of mechanical ventilation of the granary. The simulation results, including temperature field, flow field and pressure field results, show that the cone shaped base of grain granary is better than flat shaped base. It is an optimal project that the main wind pipe opens with mesh only in the bottom. In addition, four vertical guide plates were set up around the main wind pipe, which have the function of saving energy and reducing consumption.

scholarly journals A Study on the Utilization of Natural Ventilation Systems in Institutional Buildings

2019 ◽  
Vol 7 (1) ◽  
pp. 73-81
Author(s):  
N Anuja ◽  
N Amutha Priya
Keyword(s):  
Mechanical Ventilation ◽  
Energy Consumption ◽  
Wind Speed ◽  
Energy Management ◽  
Energy Demand ◽  
Natural Ventilation ◽  
Wind Pressure ◽  
Air Flow Rate ◽  
Change Rate ◽  
Air Change Rate

In Buildings, Energy Management is an important sector. Use of natural ventilation is the only way to minimise the overall energy consumption in buildings. Natural ventilation at a point can vary significantly for every second due to the climatic change. This paper has investigated energy demand problems due to ventilation in an institutional building located in India and gives satisfactory solutions to the problem. The main aim is to utilise maximum natural ventilation instead of artificial systems by reducing the energy bills in the Institutional building. Several Factors such as Wind speed, Wind pressure, Mechanical Ventilation, Air Flow Rate, Air Change Rate, Ventilation Air Change Requirements, Ventilation at various points in a Classroom are considered, and a Questionnaire Survey is conducted among the students.

scholarly journals The Resistance of Ship Web Girders in Collision and Grounding

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Zhenguo Gao ◽  
Song Yang ◽  
Zhiqiang Hu
Keyword(s):  
Numerical Simulation ◽  
Analytical Method ◽  
Previous Experiment ◽  
Deformation Model ◽  
Deformation Characteristics ◽  
Concentrated Load ◽  
Reliable Assessment ◽  
Comparison Results ◽  
Simulation Based ◽  
Simulation Results

Ship web girders play an important role in ship structure performance during collision and grounding accidents. The behavior of web girders subjected to in-plane concentrated load is investigated by numerical simulation and theoretical analysis in this paper. A numerical simulation based on previous experiment is conducted to give insight to the deformation mechanism of crushing web girders. Some new important deformation characteristics are observed through the simulation results. A new theoretical deformation model is proposed featured with these deformation characteristics, and a simplified analytical method for predicting the instantaneous and mean resistances of crushing web girders is proposed. The proposed method is verified by two previous experiments and a series of numerical simulations. The agreement between the solutions by the proposed method and the experiment results is good. The comparison results between the proposed analytical method and numerical simulation results are satisfactory for most cases. The proposed analytical method will contribute to the establishment of an efficient method for fast and reliable assessment of the outcome of ship accidental collisions and grounding events.

Sign in / Sign up

Export Citation Format

Share Document