Evaporative Cracking Characteristics of the Embankment Soil Affected by the Saline Concentration

Embankment soil affected by saline can not only cause roadbed settlement, frosting, and road cracks but also cause corrosion and cracking of roadbed pipelines, which seriously affects the stability of the road. Water evaporation and dry cracking of the saline soil mainly cause soil swelling, poor water stability, and corrosive characteristics of the embankment soil. In this study, the evaporative cracking characteristics of soil with different saline concentrations were investigated. The results showed that the moisture content decreased linearly with the drying time in the early evaporation process, subsequently decreased slow down in the mid-term evaporation, and finally become got and remain a residual moisture content, which are 46.39%, 44.05%, 42.70%, and 40.27% with the increase of the saline concentration. The evaporation process with different saline concentrations in the soil can be divided into three stages: uniform evaporation stage, slow down evaporation stage, and equilibrium evaporation stage, which was consistent with the moisture content change. With the development of the drying time, the cracks gradually appeared on the soil surface, gradually deepened in the soil, and expanded the crack network. The development of cracks can be divided into three stages: the cracking preparation stage, the crack development stage, and the crack stable stage. The cracking began at high evaporation rate under high saline concentration, and the fractal dimension remained stable under similar saline concentration. The fractal dimension was gradually increased with the decrease of the moisture content and the increase of the saline concentration, respectively. The soil began to crack with larger moisture under high saline concentration. The drying cracks in the nature were consistent with the configuration of the cracks formed in the experimental results.

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FRACTAL CHARACTERIZATION OF DYNAMIC FRACTURE NETWORK EXTENSION IN POROUS MEDIA

Fractals ◽

10.1142/s0218348x17500232 ◽

2017 ◽

Vol 25 (02) ◽

pp. 1750023 ◽

Cited By ~ 97

Author(s):

JIANCHAO CAI ◽

WEI WEI ◽

XIANGYUN HU ◽

RICHENG LIU ◽

JINJIE WANG

Keyword(s):

Porous Media ◽

Fractal Dimension ◽

Moisture Content ◽

Oil And Gas ◽

Engineering Application ◽

Fracture Network ◽

Drying Time ◽

Form Complex ◽

Network Extension

Fracture network and fractured porous media as well as their transport properties have received great attentions in many fields from engineering application and basic theoretical researches. Fracture will dynamically extend in length and aperture to form complex fracture network under some external conditions such as percussion drilling, wave propagation, desiccation and hydrofracturing. The complexity of fracture network can be well quantitatively characterized by fractal dimension. In this work, the dynamic characterization of fracture network extension in porous media under drying process is measured by the improved box-counting technique, and fractal dimensions of fracture network are respectively related to drying time, average aperture, moisture content and fracture porosity. The fractal dimension increases exponentially with drying time and average aperture, and decreases with moisture content in the form of power law. Specially, the fractal dimension is approximatively increased with porosity in the form of linearity in a narrow porosity range. The transport capacity of fracture network, described by seepage coefficient, is also related to the fractal dimension with drying time in the form of exponential function. The presented fractal analysis of fracture network could also shed light on the hydrofracturing application in subsurface unconventional oil and gas reservoirs.

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Study on Critical Moisture Content of Unsaturated Evaporation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.513-517.2643 ◽

2014 ◽

Vol 513-517 ◽

pp. 2643-2646

Author(s):

Hua Zhang ◽

Wen Long Hu ◽

Jin Lu Cao

Keyword(s):

Moisture Content ◽

Thin Layer ◽

Measuring System ◽

Evaporation Process ◽

Critical Moisture Content ◽

Whole Process ◽

Critical Moisture ◽

Three Stages ◽

Soil Water Characteristic Curves ◽

Water Contents

Thin layer evaporation tests of three types of soil were conducted by a newly designed humidity-controllable evaporation and penetration measuring system and lasted for 8 days. The whole process of sample mass variation from wet to dry was recorded in the laboratory. The critical moisture content and air-dried moisture content were obtained from evaporation curve, which divided the evaporation process of thin layer unsaturated soil into three stages, including stable rate stage, reducing rate stage and residual stage. The soil water characteristic curves of soils were predicted by Arya and Paris model, the results showed that the critical moisture contents of evaporation process were the same with the water contents corresponding to residue values of SWCC, it is significant to studying on unsaturated evaporation process.

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Description of the Convective Air-Drying of a Food Model by Means of the Fractal Theory

Food Science and Technology International ◽

10.1177/1082013203035100 ◽

2003 ◽

Vol 9 (3) ◽

pp. 207-213 ◽

Cited By ~ 27

Author(s):

P. J.J. Chanona ◽

B. L. Alamilla ◽

R. R.R. Farrera ◽

R. Quevedo ◽

J. M. Aguilera ◽

...

Keyword(s):

Fractal Dimension ◽

Fractal Analysis ◽

Fractal Theory ◽

Drying Kinetics ◽

Linear Stage ◽

Equilibrium Conditions ◽

Drying Time ◽

Air Drying ◽

Three Stages ◽

Food Model

A slab-shaped model food prepared using glucose solutions and agar as jellifying agent was subjected to drying in an experimental drier. Drying kinetics and surface temperature (ST) distribution along drying were evaluated. When fractal analysis was applied to ST distributions it was possible to observe three stages: the first one, at the beginning of the process, was very short and could not be associated with a fractal dimension. The second one, by far the longest, had a constant value of the fractal dimension of the ST distribution and towards the end of the process, as temperature of the surface of the material tended to homogenise, a final linear stage was found which corresponded to equilibrium conditions. Images of the slab along drying were recorded and showed an increasing heterogeneous appearance as drying proceeds. Grey level intensity plots corresponding to these images also showed an increasing irregularity (higher values of fractal dimension) with drying time. Fractal analysis probed to be a useful tool for describing drying kinetics and for characterising images of samples subjected to dehydration.

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Pengeringan Biji Kakao dengan Pengering Surya Tipe Terowong Berpenggerak Sel Fotovoltaik di Manokwari

Agrotek ◽

10.30862/agt.v2i6.540 ◽

2018 ◽

Vol 2 (6) ◽

Author(s):

Wilson Palelingan Aman

Keyword(s):

Moisture Content ◽

Performance Test ◽

Initial Moisture Content ◽

Maximum Temperature ◽

Photovoltaic Module ◽

Cocoa Beans ◽

Drying Time ◽

Tunnel Dryer ◽

Heat Collector ◽

New Construction

<em>A research about cocoa beans drying used solar tunnel dryer with photovoltaic module driven have conducted in Manokwari. Solar tunnel dryer used in this research adapted from type Hohenheim with photovoltaic module and integrated air heat collector has been installed at the Department of Agricultural Technology, Papua State University Manokwari to dried cocoa beans. The objectives of this research were to design solar tunnel dryer and evaluate it�s performance in dryed cocoa beans. The result obtained was a new construction of solar tunnel dryer for cocoa beans with dimensions 6 m of length and 0,9 m of wide. The dryer completed with photovoltaic module to drive the blowers of hot drying air. �Performance test of the dryer showed that drying of 10 kg of cocoa beans with initial moisture content about 70% wet basis needed 13 hours of drying time to achieved final moisture content about 7,17% wet basis. The drying time achieved was faster compared than traditional solar drying that needed 20 hours of drying time. The maximum temperature achieved in drying chamber was 60 <sup>o</sup>C.</em>

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CATFISH DRYING (Clarias Batraclus) USING ‘TEKO BERSAYAP’ SOLAR DRYER

Jurnal Agroindustri ◽

10.31186/j.agroind.2.1.14-20 ◽

2012 ◽

Vol 2 (1) ◽

pp. 14-20

Author(s):

Yuwana Yuwana

Keyword(s):

Relative Humidity ◽

Moisture Content ◽

Ambient Temperature ◽

Drying Rate ◽

Drying Process ◽

Drying Time ◽

Ambient Relative Humidity ◽

Solar Dryer

Experiment on catfish drying employing ‘Teko Bersayap’ solar dryer was conducted. The result of the experiment indicated that the dryer was able to increase ambient temperature up to 44% and decrease ambient relative humidity up to 103%. Fish drying process followed equations : KAu = 74,94 e-0,03t for unsplitted fish and KAb = 79,25 e-0,09t for splitted fish, where KAu = moisture content of unsplitted fish (%), KAb = moisture content of splitted fish (%), t = drying time. Drying of unsplitted fish finished in 43.995 hours while drying of split fish completed in 15.29 hours. Splitting the fish increased 2,877 times drying rate.

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Cherry Tomato Drying: Sun versus Convective Oven

Horticulturae ◽

10.3390/horticulturae7030040 ◽

2021 ◽

Vol 7 (3) ◽

pp. 40

Author(s):

Vincenzo Alfeo ◽

Diego Planeta ◽

Salvatore Velotto ◽

Rosa Palmeri ◽

Aldo Todaro

Keyword(s):

Moisture Content ◽

Initial Moisture Content ◽

Drying Process ◽

Drying Time ◽

Oven Drying ◽

Sun Drying ◽

Different Temperatures ◽

Final Water Content ◽

Drying Curves ◽

Drying Conditions

Solar drying and convective oven drying of cherry tomatoes (Solanum lycopersicum) were compared. The changes in the chemical parameters of tomatoes and principal drying parameters were recorded during the drying process. Drying curves were fitted to several mathematical models, and the effects of air temperature during drying were evaluated by multiple regression analyses, comparing to previously reported models. Models for drying conditions indicated a final water content of 30% (semidry products) and 15% (dry products) was achieved, comparing sun-drying and convective oven drying at three different temperatures. After 26–28 h of sun drying, the tomato tissue had reached a moisture content of 15%. However, less drying time, about 10–11 h, was needed when starting with an initial moisture content of 92%. The tomato tissue had high ORAC and polyphenol content values after convective oven drying at 60 °C. The dried tomato samples had a satisfactory taste, color and antioxidant values.

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Study on Drying Characteristics of Microalgae under Different Conditions

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.724-725.296 ◽

2013 ◽

Vol 724-725 ◽

pp. 296-299

Author(s):

Chun Xiang Chen ◽

Xiao Qian Ma ◽

Xiao Cong Li ◽

Wei Ping Qin

Keyword(s):

Moisture Content ◽

Mass Loss ◽

Fresh Water ◽

Chlorella Vulgaris ◽

Drying Process ◽

Drying Time ◽

Drying Characteristics ◽

Second Stage ◽

Drying System ◽

Two Stages

To find out an alternative of coal saving, a kind of microalgae, Chlorella vulgaris (C. vulgaris) which is widespread in fresh water was studied by digital blast drying system. The effect of the moisture content, drying thickness and temperature on the drying process of C. vulgaris were investigated. The results indicated that when the drying temperature is high, the moisture content is low and the material thickness is small, the drying time is short. The drying process of C.vulgaris can be divided into two stages, and the mass loss is mainly occurred in the second stage . The results will provide guidance for design of drying process and dryer of microalgae.

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Analytical solution for soil water redistribution during evaporation process

Water Science & Technology ◽

10.2166/wst.2013.516 ◽

2013 ◽

Vol 68 (12) ◽

pp. 2545-2551 ◽

Cited By ~ 8

Author(s):

Jidong Teng ◽

Noriyuki Yasufuku ◽

Qiang Liu ◽

Shiyu Liu

Keyword(s):

Analytical Solution ◽

Water Content ◽

Soil Water ◽

Exponential Function ◽

Experimental Result ◽

Water Evaporation ◽

Evaporation Process ◽

Climate Control ◽

Water Redistribution ◽

Control Apparatus

Simulating the dynamics of soil water content and modeling soil water evaporation are critical for many environmental and agricultural strategies. The present study aims to develop an analytical solution to simulate soil water redistribution during the evaporation process. This analytical solution was derived utilizing an exponential function to describe the relation of hydraulic conductivity and water content on pressure head. The solution was obtained based on the initial condition of saturation and an exponential function to model the change of surface water content. Also, the evaporation experiments were conducted under a climate control apparatus to validate the theoretical development. Comparisons between the proposed analytical solution and experimental result are presented from the aspects of soil water redistribution, evaporative rate and cumulative evaporation. Their good agreement indicates that this analytical solution provides a reliable way to investigate the interaction of evaporation and soil water profile.

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