scholarly journals Water vapor transport to a semi-infinite material with simultaneous varying surface relative humidity and temperature

2020 ◽  
Vol 172 ◽  
pp. 04005
Author(s):  
Carl-Eric Hagentoft
Keyword(s):  
Water Vapor ◽  
Relative Humidity ◽  
Water Vapor Transport ◽  
Time Varying ◽  
Temperature Changes ◽  
Vapor Transfer ◽  
Moisture Balance ◽  
Sinusoidal Functions ◽  
The One ◽  
Water Vapor Transfer

The water vapor transfer between the indoor air and hygroscopic finishing materials is of importance for the moisture balance of the room. Most protocols for determining the effect are based on isothermal conditions and cycling relative humidity in the form of square wave or sinusoidal functions. A new analytical solution for a material exposed to a both time varying surface relative humidity and temperature is presented in the paper. The time varying temperature inside the material is assumed to follow the surface temperature throughout the material layer since the reaction time for temperature changes in a reasonable thin surface material is rather short compared with the one for moisture changes. The semi-infinite approach is justified by the fact that the penetration depth for moisture variations are very limited for diurnal variations. The analytical approach and solution are presented in the paper

scholarly journals Effect of hot calendering on physical properties and water vapor transfer resistance of bacterial cellulose films

2016 ◽  
Vol 51 (21) ◽  
pp. 9562-9572 ◽  
Author(s):  
V. L. D. Costa ◽  
A. P. Costa ◽  
M. E. Amaral ◽  
C. Oliveira ◽  
M. Gama ◽  
...  
Keyword(s):  
Water Vapor ◽  
Physical Properties ◽  
Bacterial Cellulose ◽  
Transfer Resistance ◽  
Cellulose Films ◽  
Vapor Transfer ◽  
Water Vapor Transfer

scholarly journals Heat and Water Vapor Transfer between Atmosphere and Pavement Surface Under Dry, Wet, Ice Plate and Packed Snow State

2006 ◽  
Vol 22 (3) ◽  
pp. 220-228 ◽  
Author(s):  
Akihiro Fujimoto ◽  
Hiroshi Watanabe ◽  
Teruyuki Fukuhara ◽  
Takeshi Sato ◽  
Masaki Nemoto ◽  
...  
Keyword(s):  
Water Vapor ◽  
Pavement Surface ◽  
Vapor Transfer ◽  
Water Vapor Transfer

Diffusion of water vapor through human skin in hot environment and with application of atropine

1959 ◽  
Vol 14 (2) ◽  
pp. 276-278 ◽  
Author(s):  
Konrad J. K. Buettner ◽  
Frederick F. Holmes
Keyword(s):  
Water Vapor ◽  
Relative Humidity ◽  
Human Skin ◽  
Liquid Water ◽  
Water Loss ◽  
Diffusion Resistance ◽  
Vapor Transfer ◽  
Hot Environment ◽  
Human Forearm ◽  
Very High

At room temperatures between 20° and 40°C, vapor transfer through skin of human forearm was tested with four small heated bottles containing air of humidities ranging from 2 to 100% relative humidity. Exposure times ranging from 30 to 120 minutes had no influence on results. Water loss or gain of skin were observed for the different bottles. At very high humidities, liquid water deposit on the skin was measured by weighing a blotter. Skin vapor loss decreases systematically when bottle moisture increases. This increase is enhanced at room temperatures above 24℃, where total loss into a dry bottle increases more than fivefold. This increase seems only partially caused by sweat and partially by a decrease of the skin diffusion resistance. Tourniquet and locally applied atropine did not affect vapor transfer in a cool room. In a hot room, the tourniquet lowered the vapor loss by only 20%, whereas atropine drastically curtailed vapor loss. Submitted on August 25, 1958

Diffusion of water vapor through small areas of human skin in normal environment

1959 ◽  
Vol 14 (2) ◽  
pp. 269-275 ◽  
Author(s):  
Konrad J. K. Buettner
Keyword(s):  
Water Vapor ◽  
Relative Humidity ◽  
Vapor Pressure ◽  
Skin Temperature ◽  
Horny Layer ◽  
Small Areas ◽  
Vapor Transfer ◽  
Normal Environment ◽  
Made In ◽  
Frequency Curves

Four small skin areas of the forearm were exposed concurrently to four small bottles at skin temperature. The bottles contained certain wet salts which condition the local vapor pressure. The vapor transfer between skin and bottles resulted in a measurable weight change of the bottles. One thousand tests on 250 people were made in a comfortable room. Below a critical humidity, vapor left the skin; above this ‘neutral relative humidity’ (NRH) the skin gained vapor. A small portion of this skin intake is used to moisten the horny layer. Correcting for this, the average of all tests is NRH = 86%. Frequency curves show two significant maxima besides that around 86%, viz. one around a NRH of 60–70%, generally concurrent with edema, and one above 90% NRH, usually observed on sweating skin. Length of exposure (30 min.-8 hr.), season and skin temperature (excluding sweating) have no recognizable influence on NRH. Submitted on August 25, 1958

scholarly journals Dynamic Simulation Modeling of Heat and Water Vapor Transfer in a Fluid-Roof Greenhouse.

2001 ◽  
Vol 57 (4) ◽  
pp. 169-182 ◽  
Author(s):  
Ahmed M. ABDEL-GHANY ◽  
Toyoki KOZAI ◽  
Nabil Y. ABDEL-SHAFI ◽  
Ibrahem S. TAHA ◽  
Ahmed S. HUZAYYIN
Keyword(s):  
Water Vapor ◽  
Dynamic Simulation ◽  
Simulation Modeling ◽  
Vapor Transfer ◽  
Water Vapor Transfer

scholarly journals Heat and water vapor transfer in the wake of a falling ice sphere and its implication for secondary ice formation in clouds

2019 ◽  
Vol 21 (4) ◽  
pp. 043043 ◽  
Author(s):  
Agathe Chouippe ◽  
Michael Krayer ◽  
Markus Uhlmann ◽  
Jan Dušek ◽  
Alexei Kiselev ◽  
...  
Keyword(s):  
Water Vapor ◽  
Ice Formation ◽  
Vapor Transfer ◽  
Water Vapor Transfer

Water Vapor Transfer in the Soil by Thermal Gradients and Its Control

1963 ◽  
Vol 6 (3) ◽  
pp. 0244-0248 ◽  
Author(s):  
R. K. Matthes ◽  
Jr. and H. D. Bowen
Keyword(s):  
Water Vapor ◽  
Thermal Gradients ◽  
Vapor Transfer ◽  
Water Vapor Transfer
Sign in / Sign up

Export Citation Format

Share Document