scholarly journals Study on the influence of underwear on local thermal and moisture comfort of human body

2020 ◽  
pp. 229-229
Author(s):  
Pengpeng Cheng ◽  
Daoling Chen ◽  
Jianping Wang
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Skin Temperature ◽  
Human Body ◽  
Subjective Evaluation ◽  
Composite Fiber ◽  
Clothing Comfort ◽  
Temperature And Humidity ◽  
Better Than ◽  
Objective And Subjective Evaluation

In order to study the influence of underwear on human thermal and moisture comfort in different sports conditions, the objective and subjective evaluation of underwear (including undershirt and underpants) made of three kinds of fabrics were carried out, and the underwear comfort model was established by computational fluid dynamics, and the application prospect of computational fluid dynamics technology in the field of clothing comfort research was prospected. The results show: 1. the underwear combination of different fabrics has certain influence on the thermal and moisture comfort of human body, and the thermal and moisture of fabric of composite fiber is better than that of fabric of single fiber; 2. the temperature and humidity of chest, back, hip and thighs of the human body in different motion states change, and the temperature and humidity of the chest and back change greatly; 3. computational fluid dynamics can accurately predict human skin temperature.

Use of computational fluid dynamics to model reservoir mixing and destratification

1998 ◽  
Vol 37 (2) ◽  
pp. 227-234
Author(s):  
Julian D. Cox ◽  
Martin B. Padley ◽  
Joe Hannon
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Reverse Flow ◽  
Dynamics Model ◽  
Artificial Mixing ◽  
Effective Operation ◽  
Different Types ◽  
Blade Mixer ◽  
Perforated Pipe ◽  
Better Than

Destratification of reservoirs by the use of artificial mixing is a method of improving the impounded water quality. In order to design a destratification device at Stocks Reservoir, NW England, a Computational Fluid Dynamics model was used to trial different types and sizes of mixing device. It was found that a perforated pipe bubble mixing device performed far better than a large banana blade mixer at destratifying Stocks Reservoir. Two important criteria for the effective operation of a mixing device were established. These were a minimum upflow velocity of entrained water through the reservoir, and the need for a reverse flow along the surface of the reservoir away from the abstraction point. These criteria have been incorporated into design equations which can be extended to use at other reservoirs. A bubble mixer was installed at Stocks Reservoir, and has been shown to fully destratify the reservoir and to reduce the levels of dissolved manganese in the water by more than 50%.

scholarly journals Wind Velocity Decreasing Effects of Windbreak Fence for Snowfall Measurement

2014 ◽  
Vol 2014 ◽  
pp. 1-20
Author(s):  
Ki-Pyo You ◽  
Young-Moon Kim
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Wind Velocity ◽  
Wind Tunnel Test ◽  
Field Measurements ◽  
Wind Flow ◽  
Dynamics Analysis ◽  
Computational Fluid Dynamics Analysis ◽  
Better Than ◽  
Velocity Decrease

Meteorological observatories use measuring boards on even ground in open areas to measure the amount of snowfall. In order to measure the amount of snowfall, areas unaffected by wind should be found. This study tried to determine the internal wind flow inside a windbreak fence, identifying an area unaffected by wind in order to measure the snowfall. We performed a computational fluid dynamics analysis and wind tunnel test, conducted field measurements of the type and height of the windbreak fence, and analyzed the wind flow inside the fence. The results showed that a double windbreak fence was better than a single windbreak fence for decreasing wind velocity. The double fence (width 4 m, height 60 cm, and fixed on the bottom) has the greatest wind velocity decrease rate at the central part of octagonal windbreak.

Effect of underwear on microclimate heat transfer in clothing based on computational fluid dynamics simulation

2019 ◽  
Vol 90 (11-12) ◽  
pp. 1262-1276
Author(s):  
Pengpeng Cheng ◽  
Daoling Chen ◽  
Jianping Wang
Keyword(s):  
Heat Transfer ◽  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Human Body ◽  
Physical Phenomenon ◽  
Age Groups ◽  
Great Influence ◽  
Dynamics Simulation ◽  
Average Temperature ◽  
Average Skin

In order to study the influence of underwear on microclimate heat transfer among different age groups, this study measured the temperature of the microclimate layer corresponding to the main parts of the human body or the key parts that affect average skin temperature. A computational fluid dynamics numerical model was then used to simulate the influence of underwear on heat transfer between the human body and the microenvironment and to explore the physical phenomenon. The results obtained show that underwear has a great influence on the average temperature of the microclimatic air layer, especially the air layer at the upper arm, forearm, and thigh. The findings of this study provide fundamental knowledge to improve the thermal comfort of underwear.

Optimal Design of Inlet Structure of High-Pressure Tubular Reactor Jacket

2011 ◽  
Vol 311-313 ◽  
pp. 1254-1257
Author(s):  
Xiao Hui Ji ◽  
Wei Liu
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
High Pressure ◽  
Shear Stress ◽  
Flow Characteristic ◽  
Tubular Reactor ◽  
The Other ◽  
The Third ◽  
Tube Structure ◽  
Better Than

Flow characteristic of the desalted water influenced by three inlet structures in different diameter nomal tube, equal diameter nomal tube and tangential tube inlet of the jacketed tube in high-pressure tubular reactor was investigated based on computational fluid dynamics. The results show that the desalted water flow forms a region where the flow velocity is close to zero in the different diameter nomal tube structure and temperature of the desalted water in this region raises notablely. It is also found that the peaks of the shear stress occur at wall inside near inlet of the jacket. The other structures avoid in large extent advent of the former two phenomena and obviously reduce the shear stress value at wall. From the results, the second inlet structure is better than the third and the third better than the first.

Computational Fluid Dynamics Simulation of Influence of Different Intervals of Product to the Huge Cold Store

2013 ◽  
Vol 740 ◽  
pp. 226-231
Author(s):  
Jing Xie ◽  
Chen Miao ◽  
Yi Tang ◽  
Jin Feng Wang ◽  
Yue Zhao
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Air Flow ◽  
Vertical Direction ◽  
Flow Distribution ◽  
Experimental Methods ◽  
Dynamics Simulation ◽  
Computational Fluid Dynamics Simulation ◽  
Cold Store ◽  
Better Than

The cold store has developed rapidly since 1990s in China. The unreasonable air flow distribution in cold stores hasn't been solved effectually because of lacking of experimental methods. The uniform air flied can improve the effect of store and save the refrigeration cost in the store. In this article, the air flow distribution was simulated with different intervals between products in a huge commercial cold store based on the previous simulation and experimental experience. The results showed that the interval of 10cm between products at vertical direction was better than that of 15cm for storage.

Computational Fluid Dynamics Applicable to Cloth Design

2009 ◽  
Author(s):  
Ana M. F. Cunha ◽  
Jose´ C. F. Teixeira ◽  
Senhorinha F. C. F. Teixeira
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Human Body ◽  
Thermal Manikin ◽  
Clothing Insulation ◽  
Mass Transfer Processes ◽  
Different Temperatures ◽  
Computational Fluid Dynamics Cfd ◽  
Combined Simulation

Increasingly, different concepts such as safety, hygiene and comfort interact in the characterization of the workplaces. Being comfortable during periods of low activity, seems to be a requirement for most people and, secondly, in other sectors where performance is critical, the priorities are different. In both cases, the intellectual and physical performance is strongly affected by the sensation of thermal comfort. Thus, various approaches can be applied to provide comfort, for example, in the design of buildings and the selection of appropriate clothing. Comfortable clothing is a complex and interdisciplinary concept, consisting of a balance of the sensorial, psychological and physiological aspects [1, 2]. In objective terms, the behavior of the human body depends on several factors: temperature, air velocity and humidity, production of metabolic heat and clothing insulation. All these factors determine the heat and mass transfer processes between the human body and the environment. The Computational Fluid Dynamics (CFD) numerical simulation has been a powerful tool in this investigation field. A combined simulation of a room and a thermal manikin has been developed in the FLUENT code. Using a manikin with real dimensions, divided into parts with different temperatures, seems important to give accurate fluid flow and moisture distributions.

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