scholarly journals Theoretical Drying Model of Water Vapor Pressure for Imbibed Porous Material with Sea Water subjected to Weather Conditions

2021 ◽  
Vol 87 (2) ◽  
pp. 127-136
Author(s):  
Sherif Adham Mohamed
Keyword(s):  
Water Vapor ◽  
Porous Material ◽  
Vapor Pressure ◽  
Sea Water ◽  
Water Vapor Pressure ◽  
Atmospheric Condition ◽  
Mass Conservation ◽  
Weather Conditions ◽  
Concrete Block ◽  
Drying Model

The drying model of porous material has been studied and solved. The drying model solves the drying of porous material if the porous material is saturated or unsaturated with salt solution. Local thermodynamic equilibrium was not assumed in the mathematical model for describing the multi-phase flow in the unsaturated porous media using the energy and mass conservation equations to describe the heat and mass transfer during the drying. The vapor pressure inside porous material voids is built from the vapor mass transport through material thickness and from the void’s water content evaporation. The new equation in the model is water vapor pressure’s equation. The drying model included advection and capillary transport of the water in porous material pores, the gases transport by advection and diffusion and soluble salt transports by diffusion only. The environment of the boundary condition of the model is atmospheric condition in the day’s hours. The model consists of 5 equations for mass and heat transfer phenomenon. The model was solved by Matlab software. The case study of the model is concrete block.

Sea water vapor pressure based on the Cisternas–Lam model

2016 ◽  
Vol 57 (50) ◽  
pp. 23651-23660 ◽  
Author(s):  
Luis A. Cisternas ◽  
Renato Acosta-Flores ◽  
Višnja Musič
Keyword(s):  
Water Vapor ◽  
Vapor Pressure ◽  
Sea Water ◽  
Water Vapor Pressure

scholarly journals Water vapor pressure trends in south and southwest Iran

MAUSAM ◽  
2021 ◽  
Vol 68 (2) ◽  
pp. 335-348
Author(s):  
YOUNES KHOSRAVI ◽  
HASAN LASHKARI ◽  
HOSEIN ASAKEREH
Keyword(s):  
Time Series ◽  
Water Vapor ◽  
Vapor Pressure ◽  
Water Vapor Pressure ◽  
Sen’S Slope Estimator ◽  
Sen’S Slope ◽  
Ground Station ◽  
Mk Test ◽  
Slope Estimator ◽  
The Persian Gulf

Recognitionanddetectionofclimaticparameters inhave animportant role inclimate change monitoring. In this study, the analysis of oneofthe most importantparameters, water vapor pressure (WVP), was investigated. For this purpose, two non-parametric techniques, Mann-Kendall and Sen's Slope Estimator, were used to analyze the WVP trend and to determine the magnitude of the trends, respectively. To analyze these tests, ground station observations [10 stations for period of 44 years (1967-2010)] and gridded data [pixels with the dimension of 9 × 9 km over a 30-year period (1981-2010)] in South and SouthwestofIran were used. By programming in MATLAB software, the monthly, seasonal and annual WVP time series were extracted and MK and Sen's slope estimator tests were done. The results of monthly MK test on ground station observations showed that the significant downward trends are more considerable than significant upward trends. It also showed that the WVP highest frequency was more in warm months, April to September and the highest frequency of significant trends slope was in February and May. The spatial distribution of MK test of monthly gridded WVP time series showed that the upward trends were detected mostly in western zone and near the Persian Gulf in August. On the other hand, the downward trends through months. The maximum and minimum values of positive trends slope occurred in warm months and cold months, respectively. The analysis of the MK test of the annual WVP time series indicated the upward significant trends in the southeast and southwest zones of study area.  

Temperature and Water Vapor Pressure Effects on the Friction Coefficient of Hydrogenated Diamondlike Carbon Films

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Pamela L. Dickrell ◽  
N. Argibay ◽  
Osman L. Eryilmaz ◽  
Ali Erdemir ◽  
W. Gregory Sawyer
Keyword(s):  
Water Vapor ◽  
Friction Coefficient ◽  
Vapor Pressure ◽  
Water Vapor Pressure ◽  
Carbon Film ◽  
Transient Behavior ◽  
Carbon Films ◽  
Pressure Effects ◽  
Diamondlike Carbon ◽  
Gas Surface Interactions

Microtribological measurements of a hydrogenated diamondlike carbon film in controlled gaseous environments show that water vapor plays a significant role in the friction coefficient. These experiments reveal an initial high friction transient behavior that does not reoccur even after extended periods of exposure to low partial pressures of H2O and O2. Experiments varying both water vapor pressure and sample temperature show trends of a decreasing friction coefficient as a function of both the decreasing water vapor pressure and the increasing substrate temperature. Theses trends are examined with regard to first order gas-surface interactions. Model fits give activation energies on the order of 40 kJ/mol, which is consistent with water vapor desorption.

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