Gravitational Flow Of Water Research Articles

Irrigation using Natural Energy Sources

Renewable energy systems are being used all over the world in isolation or on hybrid modes. No work is available for integrating all existing green energy sources to develop and design a model for specific application. No template is readily available to assess and implement the most appropriate mix of the renewable sources of energy for specific purpose of irrigation in hilly areas. The proposed flexible modular design can be easily adapted for different levels of applications. This will be based on requirement and availability of water in the region of interest viz. Uttarakhand hills in lower western Himalayas. The paper dwells upon utilising wind, solar, gravitational flow of water, hydraulic hammer and barometric pressure for capillary lift.

Particle removal mechanisms in synergistic aging of polymers and glass reinforced polymer composites under combined UV and water

Complex degradation processes occur during synergistic aging of polymers and Polymer Matrix Composites (PMCs) by UV radiation and water condensation at elevated temperatures. The damage is associated with the formation of surface micro-particles and their subsequent removal by slowly moving water. The particle removal significantly accelerates the overall degradation process of the materials [1]. In this research, hydrodynamic effects have been analyzed to explain removals of micro-particles from polymeric materials affected by synergistic aging by UV and water. Viscous shear stresses generated by slowly moving water were determined on polymer surfaces as a function of surface morphology, flow rates, and volumetric forces. Subsequently, a new micro-particle removal mechanism was suggested by comparing the adhesion forces calculated using the Johnson-Kendall-Roberts (JKR) model and the Hamaker approach with the drag forces created by slow water flows. In the experimental part, the particle removal mechanism has been verified on an inclined unidirectional glass/epoxy surface with randomly distributed epoxy particles subjected to a gravitational flow of water. It has been shown that the movement of polymer particles on polymer/composite surfaces depends very strongly on particle sizes, water velocity and surface morphology. The research presented in this study clearly explains why polymer and GRP degradation by UV in the presence of occasional slow water flows is much faster than just by the individual exposure to UV radiation reported in Ref. 1.

Using Lidar and GIS to Investigate Water and Soil Management in the Agricultural Terracing at Caracol, Belize

AbstractIn April 2009, a lidar survey flown by the National Center for Airborne Laser Mapping recorded 200 square kilometers of terrain that comprised the Classic Period Maya city of Caracol, Belize. The data revealed a highly manipulated landscape of dense settlement, agricultural terraces, and residential reservoirs. Literature on Maya agriculture has discussed the benefits of terraces in controlling soil erosion, retaining water, and managing the gravitational flow of water; however, until now these benefits have not been quantified or demonstrated on the ground at scale. This research utilizes these lidar data and data derivatives in order to test the degree to which the ancient Maya manipulated their environment and were able to support large-scale populations through their landscape management practices. As such, the research provides evidence supporting the significance of agricultural terraces and their impact on limiting soil erosion, increasing water retention, and permitting flow control over rainfall runoff. This research also highlights the conscious effort by the ancient Maya to manage the hydrology of their terraced landscape.

Preferential water flows in an ordinary chernozem of the Azov Plain

Preferential flows of gravitational water were studied with the use of modified grid lysimeters in an ordinary chernozem developed from loesslike loam on the slightly inclined Azov Plain. Within horizontal soil sections, the lysimetric water flow changed from high values to the complete absence at short (5–10 cm) distances. The funnel type of gravitational water flow concentration was noted. According to the character of changes in water infiltration during two consecutive cycles of soil watering, the zones with stable and altering (both increasing and decreasing) water flows were distinguished. No definite regularities of the changes in the concentration of the added label (chloride salts) in dependence on the intensity of the water flows and on the depth of the lysimeter installation were noted. Five days after the infiltration of considerable amounts of water (250 and 135 mm) into the soil monolith, the spatial variability of the concentration of the label was seen at distances of 5–15 cm.

Gravitational water flow enhances the colonization of spinach roots in soil by plant growth-promoting Pseudomonas

Root colonization by a plant growth-promoting Pseudomonas (H3R strain) was examined to determine whether gravitational water flow affects the bacterial distribution on spinach roots. Firstly, the effect of the amount of irrigation water or soil moisture content on the distribution of the H3R strain resistant to three antibiotics was examined using a rhizobox, Pseudomonas When a large amount of water was irrigated from the top of the rhizobox, the strain inoculated onto the spinach seed was detected in the lower part of the rhizobox. However, when water was supplied from the side of the rhizobox with a sprayer, the Pseudomonas strain could not be detected in the lower part of the rhizobox. Secondly, to visualize root colonization by the inoculated bacteria, Pseudomonas strains were marked with the lux gene. Spinach seeds were inoculated with the lux-marked Pseudomonas strains and grown in a pot. A plastic tube with a hole at the upper, middle, or lower position was buried in a pot. Water was supplied from a hole of the tube. The bacterial distribution on roots was observed based on bioluminescence. Only when water was supplied from the upper hole, did the bacteria colonize the whole root. When water was supplied from the middle or lower hole, the bacteria remained around the seeds. These results indicated that the effect of the gravitational water flow by irrigation is important for the spread of colonization of spinach roots by Pseudomonas strains.

A simple bubbling system for measuring radon ( 222Rn) gas concentrations in water samples based on the high solubility of radon in olive oil

Based on the different levels of solubility of radon gas in organic solvents and water, a bubbling system has been developed to transfer radon gas, dissolving naturally in water samples, to an organic solvent, i.e. olive oil, which is known to be a good solvent of radon gas. The system features the application of a fixed volume of bubbling air by introducing a fixed volume of water into a flask mounted above the system, to displace an identical volume of air from an air cylinder. Thus a gravitational flow of water is provided without the need for pumping. Then, the flushing air (radon-enriched air) is directed through a vial containing olive oil, to achieve deposition of the radon gas by another bubbling process. Following this, the vial (containing olive oil) is measured by direct use of gamma ray spectrometry, without the need of any chemical or physical processing of the samples. Using a standard solution of 226Ra/ 222Rn, a lowest measurable concentration (LMC) of radon in water samples of 9.4 Bq L −1 has been achieved (below the maximum contaminant level of 11 Bq L −1).

CREATING A PROTECTED DIFFUSION ZONE

In intensive, open horticultural crop production systems, quantities of water and soluble fertilizers are convected by gravitational and evaporative flow through the plant root zone, with only a small fraction being captured by the plant root system. Principles and concepts developed in creating a protected diffusion zone (PDZ) within the closed, insulated pallet system (CIPS) have been extrapolated to create a protected zone for fertilizer diffusion in a surface-irrigated plant container or open field/landscape planting. Incorporating additional evaporative and gravitational water flow barriers has resulted in a semiclosed field system to minimize quantities of water and fertilizer applied and lost from the plant root zone. Use of saline water is more feasible in PDZ system than in open systems.

Heterogeneity of unsaturated gravitational flow of water through beds of large particles. Technical note : Dexter, A R Water Resour ResV29, N6, June 1993, P1859–1862

Heterogeneity of unsaturated gravitational flow of water through beds of large particles. Technical note : Dexter, A R Water Resour ResV29, N6, June 1993, P1859–1862

Evaluating Nitrate Recovery by Ion‐Exchange Resin Bags

AbstractIon‐exchange resin (IER) bags were tested as traps for leached soil NO−3‐N. In laboratory experiments, IER bags recovered 84.7% of the NO−3‐N from solutions containing 0.09 to 40.74 g NO−3‐N kg−1 resin, but recovery decreased at higher concentrations. In soil columns, NO−3‐N recovery was poor (36.2%) when NO−3‐N moved slowly through the soil profile after a rapid single pulse, but improved (87.1%) when higher flow was sustained. In the field, estimates of leached NO−3‐N using IER bags fell within the range of values estimated from soil cores and suction lysimeters. Advantages of IER bags are attributed to cumulative recovery of NO−3‐N during passive interception of gravitational water flow.

Heterogeneity of unsaturated, gravitational flow of water through beds of large particles

Water was applied uniformly as a fine spray onto the surface of beds of nonabsorbing particles. The outflow at the base of the bed was collected separately from 74 equal, small collecting areas. The spatial heterogeneity of the outflow was determined as a function of bed height, particle diameter, and the size of the collection areas. The results show that spatial heterogeneity develops with increasing bed depth and decreases with increasing area of the collectors. Particle diameter has only a small effect on flow heterogeneity. It is hypothesized that spatial heterogeneity develops because individual flow pathways, or rivulets, take a “random walk” downward through the particles in the bed. When two flows meet by chance, they combine and stay combined. In this way, the number of rivulets per unit cross‐sectional area of bed decreases with increasing depth, and the spatial flow heterogeneity increases. It is proposed that this process may occur in the tilled layer of soil.

The environmental behavior of chemicals in soil: Atrazine as an example

In this work a mathematical model has been developed and used to estimate the soil vertical distribution of Atrazine dispersed in the environment. Water transport, rise due to capillarity, and partition among soil-contained water, air, and organic matter, as well as degradation processes, are considered. As far as the vertical mobility in soil is concerned, the model has been derived from that proposed by P. H. Nichols, A. Walker, and R. J. Baker ((1982). Pestic. Sci. 12, 484–494). Such a model has been extended to include a procedure which takes into account the Atrazine mobility due to gravitational water flow. The organic carbon (O.C.) concentration gradient in soil was also considered in the evaluation when assessing partition processes, according to models by P. J. McCall et al. ((1983). Residue Rev. 13, 231–241) and D. McKay and S. Paterson ((1982). Environ. Sci. Technol. 16, 12, 654). The degradation processes are assumed to be first order, linearly related with O.C. content in soil. The application of this model to two sets of soil data demonstrated that Atrazine requires a long time (2 years or more, depending on soil features) in order to percolate at a depth comparable with those of a groundwater source.

Investigation of heat transfer and fluid friction in a viscous gravitational flow of water in a horizontal tube at qW = const

Results of an experimental investigation of local and mean heat transfer and fluid friction are given. It is shown that the heat transfer and fluid friction coefficients in the viscous gravitational regime depend on the heat supply law.