Pub Date : 2021-07-14DOI: 10.1080/23249676.2021.1947400
H. Koné, Alain Stéphane Assémian, T. Tiho, K. Adouby, K. Yao, P. Drogui
This work aims to study nitrate ions removal using Borassus aethiopum activated carbon (BA-AC) in a synthetic medium. BA-AC was prepared through artisanal method in order to provide a low-cost activated carbon. Physico-chemical characterization of BA-AC has shown a high-specific surface area (1431 m2/g). Analysis of surface morphology by scanning electron microscopy, mean pore diameter (2.76 nm) and adsorption/desorption isotherm resulted in the mesoporous adsorbent. The existence of functional groups (C = O; C–H; C–OH) was highlighted by Fourier Transform Infrared spectroscopy. A percentage of 60.56% for nitrate ions at pH 4 was reached. Pseudo-second-order kinetic and Langmuir isotherm were the most suitable models to describe adsorption process. The thermodynamic study revealed that adsorption mechanism occurs spontaneously (ΔG° 0). Enthalpy (ΔH° = 1.89 kJ.mol−1) and entropy (ΔS° = 19.03 J.mol−1K−1) values indicate an endothermic process with an increase of disorder at the solid–liquid interface.
{"title":"Borassus aethiopum activated carbon prepared for nitrate ions removal","authors":"H. Koné, Alain Stéphane Assémian, T. Tiho, K. Adouby, K. Yao, P. Drogui","doi":"10.1080/23249676.2021.1947400","DOIUrl":"https://doi.org/10.1080/23249676.2021.1947400","url":null,"abstract":"This work aims to study nitrate ions removal using Borassus aethiopum activated carbon (BA-AC) in a synthetic medium. BA-AC was prepared through artisanal method in order to provide a low-cost activated carbon. Physico-chemical characterization of BA-AC has shown a high-specific surface area (1431 m2/g). Analysis of surface morphology by scanning electron microscopy, mean pore diameter (2.76 nm) and adsorption/desorption isotherm resulted in the mesoporous adsorbent. The existence of functional groups (C = O; C–H; C–OH) was highlighted by Fourier Transform Infrared spectroscopy. A percentage of 60.56% for nitrate ions at pH 4 was reached. Pseudo-second-order kinetic and Langmuir isotherm were the most suitable models to describe adsorption process. The thermodynamic study revealed that adsorption mechanism occurs spontaneously (ΔG° 0). Enthalpy (ΔH° = 1.89 kJ.mol−1) and entropy (ΔS° = 19.03 J.mol−1K−1) values indicate an endothermic process with an increase of disorder at the solid–liquid interface.","PeriodicalId":51911,"journal":{"name":"Journal of Applied Water Engineering and Research","volume":"10 1","pages":"64 - 77"},"PeriodicalIF":1.2,"publicationDate":"2021-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249676.2021.1947400","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43340363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-08DOI: 10.1080/23249676.2021.1947401
P. Fatehbasharzad, Samira Aliasghari, A. Bazargan, S. Moftakhari Anasori Movahed
Spent caustic is a particularly harmful wastewater from petrochemical industries. It has a complex mixture of components, causing problems and difficulties for conventional treatment processes. In this study, electro-Fenton treatment was investigated as an advanced oxidation process (AOP) for the removal of sulfide from synthetic spent caustic. The effects of contributing factors such as pH, electrode distance, voltage, hydrogen peroxide (H2O2) concentration and time on sulfide removal were experimentally scrutinized. It was shown that under the optimum conditions, sulfide removal reached 97% and that the most influential factors were reaction duration and peroxide concentration. Interestingly, when adequate reaction times (above 30 min) were provided, changes in electrode distance and voltage were shown to be inconsequential. A pH of 5 and peroxide dosage above 0.5 mL/L were most effective. In order to illustrate the interaction of the independent variables on sulfide removal, statistical modeling was also carried out followed by optimization and prediction analysis. Highlights The electro-Fenton process was used for spent caustic treatment. Effects of pH, electrode distance, voltage, H2O2 concentration and time were studied. Importantly, at t > 30 min, electrode distance and voltage became insignificant. At 4.5–6.5 pH and 0.45–0.65 mL/L H2O2, optimum results are obtained. Under optimum condition 97% removal of sulfide was achieved.
{"title":"Removing sulfide from spent caustic petrochemical wastewater with electro-Fenton treatment","authors":"P. Fatehbasharzad, Samira Aliasghari, A. Bazargan, S. Moftakhari Anasori Movahed","doi":"10.1080/23249676.2021.1947401","DOIUrl":"https://doi.org/10.1080/23249676.2021.1947401","url":null,"abstract":"Spent caustic is a particularly harmful wastewater from petrochemical industries. It has a complex mixture of components, causing problems and difficulties for conventional treatment processes. In this study, electro-Fenton treatment was investigated as an advanced oxidation process (AOP) for the removal of sulfide from synthetic spent caustic. The effects of contributing factors such as pH, electrode distance, voltage, hydrogen peroxide (H2O2) concentration and time on sulfide removal were experimentally scrutinized. It was shown that under the optimum conditions, sulfide removal reached 97% and that the most influential factors were reaction duration and peroxide concentration. Interestingly, when adequate reaction times (above 30 min) were provided, changes in electrode distance and voltage were shown to be inconsequential. A pH of 5 and peroxide dosage above 0.5 mL/L were most effective. In order to illustrate the interaction of the independent variables on sulfide removal, statistical modeling was also carried out followed by optimization and prediction analysis. Highlights The electro-Fenton process was used for spent caustic treatment. Effects of pH, electrode distance, voltage, H2O2 concentration and time were studied. Importantly, at t > 30 min, electrode distance and voltage became insignificant. At 4.5–6.5 pH and 0.45–0.65 mL/L H2O2, optimum results are obtained. Under optimum condition 97% removal of sulfide was achieved.","PeriodicalId":51911,"journal":{"name":"Journal of Applied Water Engineering and Research","volume":"9 1","pages":"315 - 323"},"PeriodicalIF":1.2,"publicationDate":"2021-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249676.2021.1947401","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45498054","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/23249676.2021.1919224
S. K. Karmacharya, Nils Ruther, J. Aberle, S. M. Shrestha, M. Bishwakarma
While designing physical hydraulic model tests to investigate the efficiency of pressure flushing, it is most likely that very fine sediments of cohesive nature are required to satisfy the relevant scaling criteria. Cohesive sediments have different physical properties than sand, and a possibility to avoid such scale effects is to use lightweight materials with a specific gravity larger than water but lower than sand as model sediment. This paper addresses this issue by presenting results from laboratory experiments mimicking pressure flushing through a bottom outlet by using different lightweight materials and sand as model sediments. The results consolidate conclusions of previous studies carried out solely with sand and show that lightweight models can be used to predict the length and volume of flushing cones. Empirical relations to predict the length and volume of flushing cones are proposed and validated against a small set of experimental data from a previous study.
{"title":"Physical modelling of pressure flushing of sediment using lightweight materials","authors":"S. K. Karmacharya, Nils Ruther, J. Aberle, S. M. Shrestha, M. Bishwakarma","doi":"10.1080/23249676.2021.1919224","DOIUrl":"https://doi.org/10.1080/23249676.2021.1919224","url":null,"abstract":"While designing physical hydraulic model tests to investigate the efficiency of pressure flushing, it is most likely that very fine sediments of cohesive nature are required to satisfy the relevant scaling criteria. Cohesive sediments have different physical properties than sand, and a possibility to avoid such scale effects is to use lightweight materials with a specific gravity larger than water but lower than sand as model sediment. This paper addresses this issue by presenting results from laboratory experiments mimicking pressure flushing through a bottom outlet by using different lightweight materials and sand as model sediments. The results consolidate conclusions of previous studies carried out solely with sand and show that lightweight models can be used to predict the length and volume of flushing cones. Empirical relations to predict the length and volume of flushing cones are proposed and validated against a small set of experimental data from a previous study.","PeriodicalId":51911,"journal":{"name":"Journal of Applied Water Engineering and Research","volume":"9 1","pages":"251 - 263"},"PeriodicalIF":1.2,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249676.2021.1919224","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48399422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-03DOI: 10.1080/23249676.2021.1932617
B. R. Joshi, S. Yadav
Many areas of the world are particularly vulnerable to sedimentation. Determining the amount of soil erosion and sediment rate from watersheds would be the first step in reducing sedimentation. Soil and Water Analysis Tool (SWAT) based on Geographic Information System (GIS) was used to determine sediment yield and Sediment Delivery Ratio (SDR). This paper’s main objective is to assess the impact of land-use change on SDR at the sub-basin scale. Land-use changes indicated a vast reduction of 19% in the forest area, which causes an increase in agricultural land and commercial land. Therefore, SDR must be increased, but the study area’s average SDR trend is decreasing from 1985 to 2015. But, sub-basin-scale, sub-basins no. 17, 18, and 24 are decreasing from 1985 to 2005 and increasing from 2005 to 2015.
{"title":"Effect on sediment delivery ratio by changes in land use land cover and construction of hydraulic structures at sub basin scale","authors":"B. R. Joshi, S. Yadav","doi":"10.1080/23249676.2021.1932617","DOIUrl":"https://doi.org/10.1080/23249676.2021.1932617","url":null,"abstract":"Many areas of the world are particularly vulnerable to sedimentation. Determining the amount of soil erosion and sediment rate from watersheds would be the first step in reducing sedimentation. Soil and Water Analysis Tool (SWAT) based on Geographic Information System (GIS) was used to determine sediment yield and Sediment Delivery Ratio (SDR). This paper’s main objective is to assess the impact of land-use change on SDR at the sub-basin scale. Land-use changes indicated a vast reduction of 19% in the forest area, which causes an increase in agricultural land and commercial land. Therefore, SDR must be increased, but the study area’s average SDR trend is decreasing from 1985 to 2015. But, sub-basin-scale, sub-basins no. 17, 18, and 24 are decreasing from 1985 to 2005 and increasing from 2005 to 2015.","PeriodicalId":51911,"journal":{"name":"Journal of Applied Water Engineering and Research","volume":"10 1","pages":"52 - 63"},"PeriodicalIF":1.2,"publicationDate":"2021-06-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249676.2021.1932617","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47296681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-01DOI: 10.1080/23249676.2021.1932616
M. Yuce, Musa Eşit
Various drought indices are utilized to monitor and detect drought and its probable effects. Hydro-climate parameters, including rainfall, temperature and soil moisture, are important in identifying drought phenomena. In this study, 10 notable indices (SPI, SPEI, scPDSI, CZI, MCZI, RAI, RDI, DI, PNI and ZI) have been employed to monitor drought events in the Ceyhan Basin, Turkey. The applicability of these indices and their performances corresponding to historical droughts were examined by employing eight meteorological stations. Apart from the scPDSI, other indices have shown a strong correlation for 1-month time scale, and at different time scales of 3, 6, 9 and 12 months, only the correlation between the SPI, SPEI and RDI was observed to be high. While the SPI, SPEI and RDI have demonstrated a strong correlation in perceiving drought severity categories for 1-month time scale, for longer time scales the correlation of the SPEI with the other two indices was low.
{"title":"Drought monitoring in Ceyhan Basin, Turkey","authors":"M. Yuce, Musa Eşit","doi":"10.1080/23249676.2021.1932616","DOIUrl":"https://doi.org/10.1080/23249676.2021.1932616","url":null,"abstract":"Various drought indices are utilized to monitor and detect drought and its probable effects. Hydro-climate parameters, including rainfall, temperature and soil moisture, are important in identifying drought phenomena. In this study, 10 notable indices (SPI, SPEI, scPDSI, CZI, MCZI, RAI, RDI, DI, PNI and ZI) have been employed to monitor drought events in the Ceyhan Basin, Turkey. The applicability of these indices and their performances corresponding to historical droughts were examined by employing eight meteorological stations. Apart from the scPDSI, other indices have shown a strong correlation for 1-month time scale, and at different time scales of 3, 6, 9 and 12 months, only the correlation between the SPI, SPEI and RDI was observed to be high. While the SPI, SPEI and RDI have demonstrated a strong correlation in perceiving drought severity categories for 1-month time scale, for longer time scales the correlation of the SPEI with the other two indices was low.","PeriodicalId":51911,"journal":{"name":"Journal of Applied Water Engineering and Research","volume":"9 1","pages":"293 - 314"},"PeriodicalIF":1.2,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249676.2021.1932616","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42854822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-31DOI: 10.1080/23249676.2021.1927210
D. V. Wadkar, R. Karale, M. Wagh
Inlet water quality fluctuations affect mainly coagulant dose, and outlet water quality of the water treatment plant (WTP). Many complex physical and chemical processes are involved in WTP and water distribution networks (WDN). These technologies show non-linear behavior, which is challenging to be described by linear mathematical models. Thus, there is a need to develop prediction models for coagulation dose. The present study involves the application of cascade feed-forward neural networks (CFFNN) to predict coagulant dose. CFFNN Model was developed by using the Levenberg-Marquardt Training Algorithm and Bayesian Regularization Training Algorithm to predict coagulant dose. During the development of these models, hidden nodes are varied from 15 to 60, and R is found between 0.914 and 0.947. The best results were obtained by the CFFNN model using the Bayesian Regularization Training Algorithm (CFNNCD2) with hidden node 40, where R = 0.945 for training and 0.947 for testing.
{"title":"Application of cascade feed forward neural network to predict coagulant dose","authors":"D. V. Wadkar, R. Karale, M. Wagh","doi":"10.1080/23249676.2021.1927210","DOIUrl":"https://doi.org/10.1080/23249676.2021.1927210","url":null,"abstract":"Inlet water quality fluctuations affect mainly coagulant dose, and outlet water quality of the water treatment plant (WTP). Many complex physical and chemical processes are involved in WTP and water distribution networks (WDN). These technologies show non-linear behavior, which is challenging to be described by linear mathematical models. Thus, there is a need to develop prediction models for coagulation dose. The present study involves the application of cascade feed-forward neural networks (CFFNN) to predict coagulant dose. CFFNN Model was developed by using the Levenberg-Marquardt Training Algorithm and Bayesian Regularization Training Algorithm to predict coagulant dose. During the development of these models, hidden nodes are varied from 15 to 60, and R is found between 0.914 and 0.947. The best results were obtained by the CFFNN model using the Bayesian Regularization Training Algorithm (CFNNCD2) with hidden node 40, where R = 0.945 for training and 0.947 for testing.","PeriodicalId":51911,"journal":{"name":"Journal of Applied Water Engineering and Research","volume":"9 7","pages":"87 - 100"},"PeriodicalIF":1.2,"publicationDate":"2021-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249676.2021.1927210","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41300034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-11DOI: 10.1080/23249676.2021.1919227
Albashir K. Elfaqih, Said O. Belhaj
Economic and environmental factors play a crucial role in the transitioning of water desalination technologies from conventional energy sources to alternative sources, solar energy being in the forefront. This paper investigates the technical and economic merits of using three different types of powering systems: the National Electric Grid (Grid), a Standalone (Off-Grid) Photovoltaic (PV) System, and a Grid Connected (On-Grid) PV System to power a 100 m³/day reverse osmosis seawater desalination plant in the Mediterranean city of Tripoli-Libya. The cost analysis of product water showed significant savings in favour of On-Grid PV as a power source. Also, in this paper, the effect of interest rate on the cost of the water produced was studied. An additional finding of this paper was the impact of Off-Grid PV system oversizing to account for times of low solar irradiance on the level of utilization of the total electricity produced.
{"title":"Techno-economic comparison of three different types of powering systems","authors":"Albashir K. Elfaqih, Said O. Belhaj","doi":"10.1080/23249676.2021.1919227","DOIUrl":"https://doi.org/10.1080/23249676.2021.1919227","url":null,"abstract":"Economic and environmental factors play a crucial role in the transitioning of water desalination technologies from conventional energy sources to alternative sources, solar energy being in the forefront. This paper investigates the technical and economic merits of using three different types of powering systems: the National Electric Grid (Grid), a Standalone (Off-Grid) Photovoltaic (PV) System, and a Grid Connected (On-Grid) PV System to power a 100 m³/day reverse osmosis seawater desalination plant in the Mediterranean city of Tripoli-Libya. The cost analysis of product water showed significant savings in favour of On-Grid PV as a power source. Also, in this paper, the effect of interest rate on the cost of the water produced was studied. An additional finding of this paper was the impact of Off-Grid PV system oversizing to account for times of low solar irradiance on the level of utilization of the total electricity produced.","PeriodicalId":51911,"journal":{"name":"Journal of Applied Water Engineering and Research","volume":"10 1","pages":"16 - 26"},"PeriodicalIF":1.2,"publicationDate":"2021-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249676.2021.1919227","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41573118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-02DOI: 10.1080/23249676.2021.1919572
A. Wale, Messay Abera, Gashaw Beza
The most severe constraints for agriculture are water shortages in semi-arid areas of Northern Ethiopia. Rainfall is extremely variable; therefore, it is necessary to harvest rainwater to safeguard improved crop production. The objective of the study is to characterize, identifying problems and evaluating the performance of existing RWH systems in the Wag-Lasta areas. Tweleve RWH ponds were selected from six kebeles in the study area. Primary and secondary data were collected and evaluated using descriptive statistics to assess the technical performance of water harvesting ponds by field observation, direct measurements, and interviews with zone, woreda, kebele experts, and owners. The technical performance assessment showed that the collected runoff and system efficiency were negligible for the total rainwater catchment area. The problems in a portion of the non-functional ponds had found to be poor site selection, lack of maintenance, and standardization of techniques, and some of them were efficient with low performance.
{"title":"Performance evaluation of technical aspects of ex-situ rainwater harvesting systems at Wag-Lasta, Northern, Ethiopia","authors":"A. Wale, Messay Abera, Gashaw Beza","doi":"10.1080/23249676.2021.1919572","DOIUrl":"https://doi.org/10.1080/23249676.2021.1919572","url":null,"abstract":"The most severe constraints for agriculture are water shortages in semi-arid areas of Northern Ethiopia. Rainfall is extremely variable; therefore, it is necessary to harvest rainwater to safeguard improved crop production. The objective of the study is to characterize, identifying problems and evaluating the performance of existing RWH systems in the Wag-Lasta areas. Tweleve RWH ponds were selected from six kebeles in the study area. Primary and secondary data were collected and evaluated using descriptive statistics to assess the technical performance of water harvesting ponds by field observation, direct measurements, and interviews with zone, woreda, kebele experts, and owners. The technical performance assessment showed that the collected runoff and system efficiency were negligible for the total rainwater catchment area. The problems in a portion of the non-functional ponds had found to be poor site selection, lack of maintenance, and standardization of techniques, and some of them were efficient with low performance.","PeriodicalId":51911,"journal":{"name":"Journal of Applied Water Engineering and Research","volume":"10 1","pages":"39 - 51"},"PeriodicalIF":1.2,"publicationDate":"2021-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249676.2021.1919572","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42899668","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-02DOI: 10.1080/23249676.2021.1919226
R. Santos, E. Carvalho, M. M. C. L. Lima, R. Aleixo
Scour studies are often made at the equilibrium stage when the scour hole is stabilized and no more changes in the scour geometry occur. However, studying the scour time evolution is critical to better understand the erosion process and the main factors that control it in the short and long terms. Scour is a destructive process, therefore, in the absence of non-intrusive and real-time measurement techniques, an experimental analysis of time evolution of scour can be a time-consuming process as, for each considered instant, detailed measurements of the bed geometry must be taken. In this paper, two different strategies are applied to analyse the scour time evolution. Their results are compared and discussed. From the obtained experimental results, empirical relations between different variables were proposed. Further analysis provided scale relationships to adimensionalize the time evolution profiles. To measure the scour geometry, a structure from motion technique is employed.
{"title":"Time evolution of the scour induced by a ski jump jet","authors":"R. Santos, E. Carvalho, M. M. C. L. Lima, R. Aleixo","doi":"10.1080/23249676.2021.1919226","DOIUrl":"https://doi.org/10.1080/23249676.2021.1919226","url":null,"abstract":"Scour studies are often made at the equilibrium stage when the scour hole is stabilized and no more changes in the scour geometry occur. However, studying the scour time evolution is critical to better understand the erosion process and the main factors that control it in the short and long terms. Scour is a destructive process, therefore, in the absence of non-intrusive and real-time measurement techniques, an experimental analysis of time evolution of scour can be a time-consuming process as, for each considered instant, detailed measurements of the bed geometry must be taken. In this paper, two different strategies are applied to analyse the scour time evolution. Their results are compared and discussed. From the obtained experimental results, empirical relations between different variables were proposed. Further analysis provided scale relationships to adimensionalize the time evolution profiles. To measure the scour geometry, a structure from motion technique is employed.","PeriodicalId":51911,"journal":{"name":"Journal of Applied Water Engineering and Research","volume":"10 1","pages":"1 - 15"},"PeriodicalIF":1.2,"publicationDate":"2021-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249676.2021.1919226","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43393807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-05-02DOI: 10.1080/23249676.2021.1919225
Ehsan Afaridegan, M. Heidarpour, M. Goodarzi, Bashir Fallahi
Bridges are among the most important structures in river engineering. One of the significant causes of the destruction of bridges is local scouring around the piers. In the present research, collar and suction system both employed the upstream of the pier against local scouring. In separate experiments, the collar models were examined in different dimensions and the suction system was considered at different depth levels. Then, the combined collar-suction model was tested. The results showed that the suction system at the bed level (Z/h = 0) with the suction rate of (Qs/Q = 1.7%) had 51% efficiency; the 3D-length, 2D-width collar yielded 59% efficiency; and the combined suction-collar model had 94% efficiency in reducing local scouring of the pier by decreasing down-flow velocity, as well as the Reynolds Shear Stresses (RSSs) and Turbulence Kinetic Energy (TKE).
{"title":"Influence of suction and collar on reducing local scouring in cylindrical pier","authors":"Ehsan Afaridegan, M. Heidarpour, M. Goodarzi, Bashir Fallahi","doi":"10.1080/23249676.2021.1919225","DOIUrl":"https://doi.org/10.1080/23249676.2021.1919225","url":null,"abstract":"Bridges are among the most important structures in river engineering. One of the significant causes of the destruction of bridges is local scouring around the piers. In the present research, collar and suction system both employed the upstream of the pier against local scouring. In separate experiments, the collar models were examined in different dimensions and the suction system was considered at different depth levels. Then, the combined collar-suction model was tested. The results showed that the suction system at the bed level (Z/h = 0) with the suction rate of (Qs/Q = 1.7%) had 51% efficiency; the 3D-length, 2D-width collar yielded 59% efficiency; and the combined suction-collar model had 94% efficiency in reducing local scouring of the pier by decreasing down-flow velocity, as well as the Reynolds Shear Stresses (RSSs) and Turbulence Kinetic Energy (TKE).","PeriodicalId":51911,"journal":{"name":"Journal of Applied Water Engineering and Research","volume":"10 1","pages":"27 - 38"},"PeriodicalIF":1.2,"publicationDate":"2021-05-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/23249676.2021.1919225","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45424057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}