Computational Water, Energy, and Environmental Engineering

Journal Information
ISSN / EISSN : 2168-1562 / 2168-1570
Published by: Scientific Research Publishing, Inc. (10.4236)
Total articles ≅ 134
Archived in
SHERPA/ROMEO
Filter:

Latest articles in this journal

Ziyang Feng
Computational Water, Energy, and Environmental Engineering, Volume 10, pp 131-139; https://doi.org/10.4236/cweee.2021.104010

Abstract:
Taking 91105 working face as the research object, the observation method of water flowing fractured zone and the layout of mining holes were determined by analyzing the field geological structure. It was shown that the fractured zone height and the ratio given by the measured method were 52.33 and 12.46, respectively. By the numerical simulation method with the software of UDEC, the fractured zone height and the ratio were 42.5 and 10.12. By comparison of measured height data and UDEC numerical simulation, there were some differences between the measured height and the calculated results of UDEC numerical simulation method. The method of simulation can be used as the technical basis for the design of waterproof coal pillar in the future.
Hamidatu S. Darimani, Neolli Kpoda, Sumaila M. Suleman, Alhassan Luut
Computational Water, Energy, and Environmental Engineering, Volume 10, pp 82-94; https://doi.org/10.4236/cweee.2021.102006

Abstract:
This study was conducted to evaluate the water application uniformity for a drip irrigation system, considering the water quality and the duration of usage. The uniformity parameters, Emission Uniformity (EU %) and Uniformity Coefficient (UC %) were determined for the drip irrigation system installed over a year of performance. The procedures are based on taking measurements of emitter discharge along selected driplines on a sub-main. The catch can be identified as L1A, L1B, L1C, L1D, same for L2A to L2D, L3A to L3D and L4A to L4D. This gave a total of sixteen (16) measurement positions as there were 4 driplines. Results indicated that the uniformity of water application was 90% indicating that the emitter was still good after a year of installation. The average discharge rate was 0.57 l/h. The uniformity coefficient (UC %) for the gravity-fed drip irrigation system was 78%, indicating good water application and was quite significant for the evaluation of the uniform distribution of water for the design. The expansion of this irrigation method in rural communities could contribute to relevant water savings in most areas of the Upper West Region of Ghana.
Bilal Kemal, Dereje Adeba
Computational Water, Energy, and Environmental Engineering, Volume 10, pp 155-168; https://doi.org/10.4236/cweee.2021.104012

Abstract:
Dabus sub-basin is one of the main tributaries of Blue Nile with a considerable surface water potential which can be used for hydro power, irrigation, and water supply. Lack of studies regarding surface water potential and demands at the sub-basin level is the reason why this potential was underutilized. The objective of this study is to assess the surface water potential and evaluate the current and future demand by using Water Evaluation and Planning (WEAP) model at Dabus sub-basin. The model was constructed on four different scenarios starting from the current account (2020) wherein all the data is filled into the model to estimate the surface water potential and demands for different sectors. The scenarios include Scenario 1: reference scenario; Scenario 2: Change in population growth rate; Scenario 3: Irrigation water demand projection; and Scenario 4: Increased domestic water demand. The scenario has helped in analyzing “what if” questions. For all the scenarios the overall demand, coverage and unmet demand were analyzed based on three-time horizon as (2020-2030, 2030-2040, and 2040-2050). The model estimated the average annual flow as 6.536 Billion Cubic Meter (BCM) which is generated from annual precipitation of 14.987 BCM. The model showed 100% demand coverage for all the scenarios except the irrigation demand projection scenario which have unmet demand on some of the months of the year.
Tawheed Mohammed Elheesin Shareef, Zhongming Ma, Juan Chen, Xiaoxia Niu
Computational Water, Energy, and Environmental Engineering, Volume 10, pp 18-35; https://doi.org/10.4236/cweee.2021.101002

Abstract:
Water scarcity is relative and variable concept that can occur at any level of supply and demand. It is also a social construct, which is linked to the intervention in the water cycle and changes over time as a result of natural hydrological change. It is more severe when water acts as a backbone in economic policies, planning and management methods. Water scarcity can be expected to increase with most forms of economic development, but, if properly identified, many of its causes can be expected and avoided or mitigated. However, the limited irrigation management is considered a very important issue in the agricultural scope. Therefore, in this study, the relationship between water, crop production, photosynthesis, crop transpiration, crop growth, crop yields and water use efficiency have been discussed under limited irrigation conditions. However, the crops have some ability to adapt and resist against limited irrigation. Hence, under high temperate conditions, this is a shortage of water and photosynthesis is decreased with a pore (stoma) restraining. At the same time, the evapotranspiration reaches to the utmost value and the water use efficiency rises because of optimal monitoring of leaf pore (stoma). Therefore, the modality which is the reduction of the risks and improving industrial control in incomplete irrigation are the chief constraints of providing irrigation water in the future, which leads to increased crop production and ultimately providing a provision of food security.
Ernest Kyekyere, Hiram Ndiritu, Meshack Hawi, Polline Mwambe
Computational Water, Energy, and Environmental Engineering, Volume 10, pp 37-48; https://doi.org/10.4236/cweee.2021.102003

Abstract:
Solar water heaters which provide a cost-effective and environmental friendly approach to hot water generation are in widespread application. Evacuated tube solar water heaters perform better than flat plate solar water heaters as a result of their greater surface area exposed for sunlight absorption. Water-in-glass evacuated tube solar water heaters are widely used as compared to heat-pipe solar water heaters due to their short payback periods. In this study, the performance of water-in-glass evacuated tube solar water heater is investigated through experiments under the climatic conditions in Kenya. The results revealed a daily efficiency range of 0.58 - 0.65 and a daily final outlet temperature greater than 55°C given an initial temperature of 25°C.
Andrea Fischer, Jones S. Silva, Alexandre Beluco
Computational Water, Energy, and Environmental Engineering, Volume 10, pp 1-17; https://doi.org/10.4236/cweee.2021.101001

Abstract:
Some types of renewable energy have been experiencing rapid evolution in recent decades, notably among the energies associated with the oceans, such as wave and current energies. The development of new energy conversion technologies for these two forms of energy has been offering a large number of equipment configurations and plant geometries for energy conversion. This process can be implemented aiming at the result of feasibility studies in places with energy potentials, establishing minimum feasibility limits to be reached. This work aims to contribute in this sense with a feasibility study of a system with ocean wave power plants and with socio-current power plants to be operated on the southern coast of Brazil. This study evaluates a hybrid system with contributions from energy supplies obtained from wave plants and current plants, connected to the grid and supplying the demand of the municipalities in the North Coast region of the State of Rio Grande do Sul, the southernmost state of Brazil. The study was carried out with simulations with the Homer Legacy software, with some adaptations for the simulation of ocean wave plants and ocean current plants. The results indicate that the ocean wave power plants were viable in the vast majority of simulated scenarios, while the ocean current power plants were viable in the scenarios with more intense average ocean current speeds and with more expensive energy acquired from the interconnected system.
Davis Sibale, Godfrey Mwenelupembe, Sylvester Chikabvumbwa, Sylvester Chisale
Computational Water, Energy, and Environmental Engineering, Volume 10, pp 95-107; https://doi.org/10.4236/cweee.2021.103007

Abstract:
This study evaluated the water delivery performance of Nkhafi irrigation scheme based on adequacy, water delivery efficiency, equity, dependability and irrigation efficiency. Primary data were collected from field measurements, scheduled interviews, group discussions and use of a structured questionnaire. CROPWAT 8.0 computer model was used to determine crop water requirements and irrigation requirements. The results revealed that adequacy, water delivery efficiency, equity, dependability and overall water delivery performance were (0.74; 0.82), (0.70; 0.80), (0.15; 0.20), (0.11; 0.21) and (0.80; 0.80) for 2017 and 2018 seasons respectively. The scheme overall irrigation efficiencies were 20% and 25% for 2017 and 2018 respectively. These findings revealed that scheme users failed to deliver adequate and dependable water in an effective manner in both growing seasons. This occurred due to insufficient water supply, poor irrigation scheduling, lack of adequate knowledge and skills in operating and rehabilitating hydraulic structures, siltation and water losses through seepage in canals. Therefore, it is recommended that major maintenance works need to be done along the whole canal network in order to achieve good overall water delivery performance. Furthermore, farmers need to be trained in water management, sustainable agricultural production practices, operation and maintenance of irrigation structures. The study has provided an insight on the status of the scheme hence encouraging scheme users to improve water delivery performance.
Regine Fouda Bella, Salomé Ndjakomo Essiane, Simon Koumi Ngoh, Boris Fouotsap
Computational Water, Energy, and Environmental Engineering, Volume 10, pp 108-116; https://doi.org/10.4236/cweee.2021.103008

Abstract:
Photovoltaic cells are generally manufactured under standard test conditions. The operating conditions, very often induce performance losses different from those initially given by the manufacturer. This article presents an experimental acquisition and analysis system that integrates the synthetic efficiency ratio (SER) as a hybrid analysis tool to evaluate the performance of a monocrystalline photovoltaic solar panel, in this case the LW-MS90 panel in the city of Douala. The meteorological data obtained experimentally was used to evaluate these performances according to the manufacturer’s model in MATLAB/Simulink. By comparison with the experimental performances, the results quantify through a certain number of indices, a minimal power drop according to the acquired irradiance estimated at 3.45%. The interest of this approach is to contribute to the prediction of the operating performance of PV panels in the installation phase in non-standard areas.
Ariel Ortega, Dave Menicucci
Computational Water, Energy, and Environmental Engineering, Volume 10, pp 71-81; https://doi.org/10.4236/cweee.2021.102005

Abstract:
This article reports on a case study of the research and development of a new tool to assist in the design of rainwater cisterns. A rainwater cistern is a way to improve wildlife habitat because it can be situated in locations that do not have natural water sources, such as streams or wells that can supply water for storage. However, the design and sizing of such a system can be challenging because a number of constantly varying factors must be considered, such as changing precipitation patterns, the evaporative losses from the cistern and animal water consumption. No standardized sizing methodology currently exists for designing wildlife rainwater cisterns. In this article we present a new method for assisting in optimally sizing a rainwater cistern. We discuss how we implemented the quantitative portion of this methodology into a new Excel? model called CISMOD, which we configured for general use by wildlife professionals. We describe the methodology for designing a rainwater cistern based on standard engineering techniques. We then present and discuss our experience in applying the model to design two rainwater cisterns in an area of the Jemez Mountains in northern New Mexico, USA. The CISMOD model and a user manual are available at no cost for wildlife professionals.
Athanasios K. Margaritidis
Computational Water, Energy, and Environmental Engineering, Volume 10, pp 49-70; https://doi.org/10.4236/cweee.2021.102004

Abstract:
The purpose of this paper is to investigate the trend of precipitation in Kilkis region (Greece) at the site and regional level in various time scales. At the site level, the precipitation trend was analyzed using three tests: 1) Mann-Kendall, 2) Sen’s T and 3) Spearman while the trend slope was estimated using the Sen’s estimator. At a regional level, nonparametric spatial tests such as Regional Average Mann-Kendall (RAMK) and BECD’s (Bootstrap Empirical Cumulative Distributions) were elaborated with and without the effect of cross correlation. The trend of precipitation was noticed generally downward at annual time scale and statistically significant at 5% level of significance only in only one station. The results of the analysis of trends at the regional level showed in total the influence of cross correlation in the time series since the number of trends detected is reduced when cross correlation is preserved. Precipitation data from 12 stations were used. The study results benefit water resource management, drought mitigation, socio-economic development, and sustainable agricultural planning in the region.
Back to Top Top