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In order to determine the economic-productive, energy and environmental impacts of wind pumping in sprinkler irrigation for garlic cultivation, the investigation was carried out at "La Cuchilla" farm during 2016-2017, 2017-2018 and 2018-2019 cycles. The mass of the bulbs was 27.47 g, 27.81 g and 27.70 g, respectively, to average 27.66 g and the diameter of the bulbs reached values of 3.92 g, 4.01 g and 3.85 g, respectively. The production volume was 231,400.00 pesos per hectare, the annual costs amounted to 18,929.77 pesos per hectare and the net benefit was 212470.23 pesos per hectare. The favorable production cost per peso of 0.08 cents with a value of 11.22 obtained in the Benefit-Cost ratio was much higher than the unit was. A multi-blade mill was utilized for pumping water instead of a LEPONO brand motorized pump, used by farmers in the region. It has a flow rate of 60 L min-1, maximum head 70 m, turning speed 3400 rpm and current intensity consumed by the 11 A motor and allowed an energy saving of 27.66 kWh corresponding to 146.77 kg of CO2 equivalent per hectare no longer emitted into the atmosphere. [ABSTRACT FROM AUTHOR]

This work explores the responses of subsurface dissolved oxygen (DO) to ―Wind Pump‖ impacts of Deep Depression (DD) BOB 04 (2014) with a pre-existing cyclonic eddy based on satellite and Bio-Argo observations in the central Bay of Bengal. Results show the combined influence of the pre-existing cyclonic eddy and DD BOB 04 shoaled the oxycline from 48 m to the shallowest depth 32 m two days after the DD BOB 04. With the pre-existing cyclonic eddy, BOB 04 induced DO decrease in the subsurface for a long time of 18 days. The strong saline stratification suppressed the chlorophyll enhancement along the DD track after its passage. However, this weak DD caused the significant subsurface DO decrease owing to the upwelling. This hovered DD with a pre-existing cyclonic eddy played an important role in governing the boundary of oxygen minimum zone. [ABSTRACT FROM AUTHOR]

Abstract Wind power ramps cause large-amplitude power fluctuation which harmfully affects the stability of power system's operation. As a new issue in wind power integration, the existing ramp forecasting methods still has some imperfection, e.g., harmonization on long-term trend and short-term precision. Therefore, an advanced method is proposed in this paper, mainly focus on improving the performance of wind power ramp prediction. This method utilizes wind power curve to build a primary model which can capture the trend of wind power variation. Then, prediction residual of the primary model is corrected by a MSAR (Markov-Switching-Auto-Regression) model which combining the advantages of AR models and Markov chain. Finally, an improved swinging door algorithm is applied to extract linear segments, and ramp definitions are used to detect ramp events. Actual wind farm data is used to test the proposed method. Comparison with traditional methods are presented, the numerical results validate that the proposed approach has improved performance not only on wind power prediction but also on ramp prediction. Highlights • An advanced approach is proposed to improve ramp prediction. • The approach contains wind power prediction, residual correction, ramp detection. • Primary models capture trend of wind power variation. • Details precision are corrected by MSAR correction prediction residual. [ABSTRACT FROM AUTHOR]

Abstract An ionic wind pump is an energy-saving device that can produce a volume flow when electrodes are applied with high voltage. Compared to the traditional methods, ionic wind pumps possess the advantages of low energy consumption, no moving parts, compact structure and flexible design. In this study, a large-size ionic wind pump, consisting of many single regular hexagonal needle-ring ionic wind generators, was developed as the preliminary model. However, its experimental performance was not as good as our expectations. In order to improve this preliminary model, a simulation method was used to investigate the configuration factors of the single ionic wind pump. In the optimized model, mesh gap is 6 mm, eccentricity is 0.26, section area is 238.44 mm2 and needle electrode number is 3. In subsequent experiments, the final optimized large-size ionic wind pump showed a great promotion in velocity, and the maximum average velocity of the optimized pump was higher than the preliminary model by 13.3%. Our numerical simulation and experiment results have practical significance in designing ionic wind pumps. Highlights • A 3D numerical model is established for large size ionic wind pump. • Influences of multi-parameter on the performance of ionic wind pump are investigated by numerical and experimental method. • Optimized large-size ionic wind pump showed a great promotion in velocity. [ABSTRACT FROM AUTHOR]

Ionic wind pumps have attracted considerable interest because of their low energy consumption, compact structures, flexible designs, and lack of moving parts. However, large cross-sectional ionic wind pumps have yet to be numerically analyzed and experimentally optimized. Accordingly, this study develops a large cross-sectional ionic wind pump with multiple needles-to-mesh electrode, as well as analyzes its flow characteristics using a proposed full three-dimensional simulation method validated with experimental data. To obtain a considerably high outlet average velocity, experimental studies and numerical methods are employed to optimize the pump's configuration parameters, including needle electrode configuration, needle diameter, grid size, and gap between electrodes. The breakdown voltage and highest velocity corresponding to the breakdown voltage increase with an increase in the needle tip-to-mesh gap. After parametric optimization, a maximum velocity of 2.55 m/s and a flow rate of 2868L/min are achieved. [ABSTRACT FROM AUTHOR]

Ionic wind pumps have attracted considerable interest because of their low energy consumption, compact structures, flexible designs, and lack of moving parts. However, large cross-sectional ionic wind pumps have yet to be numerically analyzed and experimentally optimized. Accordingly, this study develops a large cross-sectional ionic wind pump with multiple needles-to-mesh electrode, as well as analyzes its flow characteristics using a proposed full three-dimensional simulation method validated with experimental data. To obtain a considerably high outlet average velocity, experimental studies and numerical methods are employed to optimize the pump's configuration parameters, including needle electrode configuration, needle diameter, grid size, and gap between electrodes. The breakdown voltage and highest velocity corresponding to the breakdown voltage increase with an increase in the needle tip-to-mesh gap. After parametric optimization, a maximum velocity of 2.55 m/s and a flow rate of 2868 L/min are achieved. [ABSTRACT FROM AUTHOR]

This study investigates the processes of occasional sea surface temperature (SST) fronts and their impacts on chlorophyll-a concentration (chl-a) in the South China Sea (SCS), based on satellite remote sensing and in situ observations in 2009-2013. The SST fronts were detected by an entropy-based edge detection algorithm method from satellite-derived SST images with a 0.011° grid size. Three offshore SST front case studies (S1, S2 and S3) at the peripheries of eddies in the northern SCS were studied. In case S1 in September 2013, two SST fronts were detected with gradient magnitudes (GMs) greater than 0.06°C km-1 in the cyclonic eddy and 0.08°C km-1 in the periphery waters, and the fronts only existed for one and two days, respectively. After three and seven days, the high chl-a was found in the strong SST front waters which were about 51 and 54% higher than the concentration in the surrounding waters. The depth of the maximum chl-a elevated from the subsurface (50 m) to the surface. In case S2 in August 2013, two SST fronts were detected at the periphery of an anti-cyclonic eddy with GM stronger than 0.06°C km-1 and only existed for one day. After two days, the chl-a in the SST front waters was about 40% higher than the levels in the surrounding waters. In case S3 in June 2009, the GM of the eddy-feature SST front was stronger than 0.12°C km-1 and existed for three days, which was generated by tropical cyclone Linfa. The chl-a in the eddy-feature phytoplankton bloom was 6 times higher than in the surrounding waters. The results show that, in general, occasional offshore SST fronts at peripheries of eddies have stronger influence on surface chl-a, comparing to those seasonal coastal and permanent offshore SST fronts, via ‘Wind Pump’ effects. [ABSTRACT FROM AUTHOR]

As the demand for advanced microelectronic devices of small form factor and high power density has increased, the capability of the miniaturized mechanical solutions for effective cooling has become critical. Electrohydrodynamic (EHD) air blowers have great potential as alternative cooling solutions over the traditional mechanical systems to meet the thermal management requirements with flexible design and considerable flow production for effective heat removal. In this paper, a numerical analysis and optimization of wire-to-plane EHD air blowers are performed based on 2-D developed models validated against previous data. For a range of blower heights from 2 to 10 mm, the location and length of the collecting plane located at the blower walls apart from the emitter wire electrode are investigated and optimized based on pumping efficiency using the ranges of fixed operating powers and voltages. Simple relations for each optimization method are presented to determine the optimal blower configuration. Results of flow rate and static pressure obtained by each optimized blower show good agreement with those predicted by EHD scaling laws previously presented. [ABSTRACT FROM PUBLISHER]

Windpumping has been identified as a process that could potentially enhance sublimation of surface snow at high forcing frequency and spawn air movement deeper in firn at lower frequencies. We performed an experiment to examine the relationship between high-frequency wind and pressure measurements within the top meter of an alpine snowpack and compared experimental results with two theoretical predictions. We find that both theoretical predictions underestimate high-frequency perturbation pressure attenuation with depth in the near-surface snowpack and the discrepancy between theory and measurement increases with perturbation pressure frequency. The impact of this result for near-surface snow is that potential enhanced sublimation will occur over a shallower snow depth than these two theories predict. Correspondingly, interstitial air mixing at depth in firn will be driven by lower frequencies than these two theories predict. While direct measurement of these energy-rich lower frequencies is beyond the scope of this paper, stationary pressure measurements validate the presence of a pressure field that could drive near-surface circulation. [ABSTRACT FROM AUTHOR]

In this paper, we address the problem of real-time fault detection in wind turbines. Starting from a data-driven fault detection method, the contribution of this paper is twofold. First, a sensor selection algorithm is proposed with the goal to reduce the computational effort of the fault detection method. Second, an analysis is performed to reduce the data acquisition time needed by the fault detection method, that is, with the goal of reducing the fault detection time. The proposed methods are tested in a benchmark wind turbine where different actuator and sensor failures are simulated. The results demonstrate the performance and effectiveness of the proposed algorithms that dramatically reduce the number of sensors and the fault detection time. [ABSTRACT FROM AUTHOR]

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This paper aims to present a mathematical model for the design of a hybrid power system (HPS) to support a remote island with 100 thousand citizens. The goal is to reduce diesel fuel consumption by adequate expansion of wind power supply. Pumped hydroelectric storage (PHS) is used in the HPS to buffer the impact of intermittent behavior of wind energy. A superstructure is proposed for HPS design, considering all possible capital decisions (e.g. the number of wind turbines) and hourly-basis operational variables (such as the amount of surplus electricity in storage and its discharge). The HPS design problem can then be formulated as a mixed-integer linear program (MILP) based on the proposed superstructure. For a given total share of wind power, the optimal mix of diesel-based and wind power supplies as well as the required capacity of PHS are determined using a four-step optimization approach, involving minimizing (i) the consumption of diesel fuel, (ii) the number of wind turbines, (iii) the size of the upper water reservoir, and (iv) the charge/discharge rates of the PHS system. In this sequential optimization, the objective value obtained in a previous step is added as an additional constraint to the next step. The proposed HPS design model is applied to a real case study of the remote K Island on the other side of Taiwan Strait using hourly-basis, year-round historical data. Inclusion of other renewable energy sources, such as photovoltaic cells and biomass-fired power plants, as well as economic perspectives will be considered in future work. [ABSTRACT FROM AUTHOR]

Keta District provides one of the best wind regimes in Ghana and farming is the main occupation of most people in the communities of the district, notably the anloga community. A small size wind pump (1.6m rotor diameter) is currently in operation in Anloga in the Keta District on pilot bases to verify its cost effectiveness compared with the hydro electric power technology. The high electricity tariff paid every month for power consumption deterred majority of the farmers using hydro electricity technology for pumping. A survey conducted revealed that out of about 50 farmers, only 29% engaged in the use of electric power for pumping whilst 69% still use the manual method. 2% of the farmers are using wind energy technology on pilot bases. Farmers in these coastal communities may have engaged in the use of wind energy for water pumping but for its high initial cost. [ABSTRACT FROM AUTHOR]

A wind pump prototype with 3.6 m rotor diameter, 19 m hub height above ground and 0.22 mm reciprocating pump stroke has been developed at the Department of Mechanical Engineering, Mekelle University. The prototype was designed and manufactured locally. Theoretical model based on combined efficiency of the rotor and the reciprocating pump was used to estimate the performance of the wind pump. One year wind speed data collected at 10 m height was extrapolated to the wind pump hub height using wind shear coefficient. The model assumed balanced rotor power and reciprocating pump, hence did not consider the effect of pump size. The theoretical model estimated the average daily discharge to be around 50 m³ and 30 m³ at 8 m and 12 m head, respectively. The prototype was tested with the same pump stroke but two different size pumps at two different heads. The pumps were with internal diameter of 55 and 70 mm and the test heads were at 8 and 12 m. Measurement of the flow rate, rotational speed and wind speed were made every 10 minutes during the test period. The data collected were analyzed to find the performance of the wind pump at the two test heads and two pump sizes. The flow rate data was plotted against binned wind speed data to determine the linear fit function. The linear fit function was then used to estimate the flow rate at any wind speed. With the 55 mm pump the measured average daily discharge was 20 and 19 m³ at 8 m and 12 m head, respectively. With the 70 mm pump the measured average daily discharge was 41 m³ and 30 m3 at 8 m and 12 m head, respectively. [ABSTRACT FROM AUTHOR]

Combined wind and pumped-storage virtual power plants, called hybrid power stations (HPS), constitute a realistic and feasible option to achieve high renewable energy source (RES) penetration levels in power systems and particularly in autonomous island grids. Technical issues arising from the integration of HPS in islands have not been sufficiently investigated yet. In this paper, the dynamic behaviour of an island system with an HPS is analysed, the effects of the various HPS operating modes on the transient behaviour and stability of the system are investigated, constraints regarding the operation of the HPS are identified and potential solutions are proposed. [ABSTRACT FROM AUTHOR]

A simple methodology was used to compare the economic feasibility of wind pump technology, solar photovoltaic pumping, diesel generators, and connection to the electrical grid to provide energy for pumping irrigation water in commercial greenhouses in Spain, Cuba and Pakistan (countries with different developmental backgrounds). The analysis took into account wind resources, distance to the grid, water storage tank volume requirements, and planting dates. Comparisons were made in terms of the levelised cost of energy associated with each system. For all three countries, if a grid connection was already in place, installing wind pumps would be economically unwise. Where no grid connection exists, the distance to the grid and the wind resource available are key factors to be taken into consideration when deciding between options: a 10% increase in the average wind speed is equivalent to a 20% reduction in the distance to the grid in terms of costs return. Finally, the water elevation has a major influence on the economic feasibility of wind pump technology, much more than, for example, on solar photovoltaic pumping technology. The results reveal that, generally, the critical factors to consider when making energy management decisions differ depending between countries. In Spain, the proximity of the electrical grid makes the connection to it the best option. In Pakistan, scarce wind resources are a serious limiting factor. Cuba, however, has good wind resources; water elevation, distance to the grid and water storage needed are the critical factors when determining the economic feasibility of wind pumping there. [ABSTRACT FROM AUTHOR]

This work demonstrates an innovative microfabricated air-cooling technology that employs an electrohydrodynamic (EHD) corona discharge (i.e., ionic wind pump) for electronics cooling applications. A single, microfabricated ionic wind pump element consists of two parallel collecting electrodes between which a single emitting tip is positioned. A grid structure on the collector electrodes can enhance the overall heat-transfer coefficient and facilitate an IC compatible batch process. The optimized devices studied exhibit an overall device area of 5.4 mm x 3.6 mm, an emitter-to-collector gap of 0.5 mm. and an emitter curvature radius of ~12.5 p.m. The manufacturing process developed for the device uses glass wafers, a single mask-based photolithography process, and a low-cost copper-based electroplating process. Various design configurations were explored and modeled computationally to investigate their influence on the cooling phenomenon. The single devices provide a high heat-transfer coefficient of up to 3200 Wlrrf K and a coefficient of performance (COP) of up to ~47. The COP was obtained by dividing the heat removal enhancement, ΔQ by the power consumed by the ionic wind pump device. A maximum applied voltage of 1.9kV, which is equivalent to approximately 38 mW of power input, is required for operation, which is significantly lower than the power required for the previously reported devices. Furthermore, the microfabricated single device exhibits a flexible and small form factor, no noise generation, high efficiency, large heat removal over a small dimension and at low power, and high reliability (no moving parts); these are characteristics required by the semiconductor industry for next generation thermal management solutions. [ABSTRACT FROM AUTHOR]

Abstract: Pumped storage is generally viewed as the most promising technology to increase renewable energy source (RES) penetration levels in power systems and particularly in small autonomous island grids. Combined wind and pumped-storage “virtual power plants”, called hybrid power stations (HPS), constitute a realistic and feasible option to achieve high penetrations, provided that their components are properly sized. In this paper, the optimum sizing is investigated for a pumped storage HPS operating in an island system. The analysis addresses the sizing of the main HPS components (hydro turbines, pumps, wind farm, reservoirs), adopting either the investor’s perspective, where the objective is to maximize the return on the HPS investment, or a system perspective, where the optimization target is the maximization of RES penetration, along with maintaining the lowest possible generation cost in the system. Genetic Algorithms (GAs) are applied for the optimization and a real isolated island power system is used as a study case. The adopted operating policy and pricing principles, which critically affect the optimal sizing of an HPS project, are based on the existing regulatory framework for storage stations in Greek islands. [Copyright &y& Elsevier]

A preceding linear stability analysis showed that the pitch and roll flutter of a wing can stop in high winds. The built-in protection and variable stroke motivated development of a flutterwing windpump, because rotors pumping with a fixed stroke usefully convert only 10% of the Betz limit of the wind's annual power. Here the stroke has to be negligible at small roll not to stiffle the start of flutter in the lightest of winds, but ultimately must increase fast to safely limit the roll amplitude by absorbing all the power of the strongest oscillation. It must be largely single-acting, just as for a piston pump down a deep well, to allow a suddenly-becalmed wing to return to vertical and then restart with a new wind. The more non-linear the pump's stroke, the larger its stiffening side effect. Other non-linearities at large amplitude include the apparent wind, the centrifuging effects of roll speed and the saturation of pitch. Smoke observation of light wind flow at full 90° tangent pitch shows remarkable stall delay until at the end of the roll swing the leading edge sheds a massive vortex to completely reverse the wing circulation. Such a wide vortex street maximises the swept area in the actuator limit where tangent blades of constant chord keep the circulation constant between stalls. Runaway of frequency and amplitude with wind speed is avoided by static gravity imbalance replacing some dynamic imbalance and the inertia and softening of a gravity pendulum, both as favoured by large scale and low design wind speed. Also helpful are not too high pitch inertia centrifuging and an aircushion on the output pipeline which reduces the stresses and pipe frictional loss as well as the pump stiffening. Then in moderate winds, the pitch can unsaturate and the wing start to feather at lower reduced frequency, containing the power and especially the downwind bending moment. In higher wind the wing then becomes stable just leaning with the wind veer. The niche is pumping as much as the prairie rotary windpumps of diameter equalling the wing length, but with only 1/2 of the mean wind or 1/8 the mean windpower density, and with much less material. Both floating and well bases and pumps have been developed for the same pendulum, wing, and nonlinear pump winch. [ABSTRACT FROM AUTHOR]

Highlights: [•] Wind and solar energies are coupled with heat pumps for buildings. [•] The system generates hot water, heating, cooling as well as electricity. [•] Wind power provides 7.6% of the yearly heat pump power demand. [•] The system yearly reduces 31.3% carbon emission. [ABSTRACT FROM AUTHOR]

Alternating pitch and heave of a foil can tap light wind or slow free water flow, as the design flow speed for an oscillating blade in any fluid is shown to be limited by its material's ratio of endurance stress to density. The free amplitude of flutter instability is inherently suited to reciprocating a pump whose stroke needs to vary to efficiently capture the changeable wind. Whereas the useful pumping work of multiblade rotary windpumps with their fixed stroke is only 10% of the ideal annual wind energy capture.Stability algebra of a foil free in pitch and elastic in heave is analytically solved for the first time to prove the stability contours of all Theodorsen frequencies radiate from the same super node of total imbalance and pitch inertia the same as for a virtual mass confined to the 3/4 chord point. The flutter frequency only involves these totals and the trail of the center of pressure behind the pitch axis. Oscillation is damped in the low ratios of total to virtual typical of hydrofoils in water but heavier-than-air wings can be unstable. High intrinsic pitch inertia ratio and trail decrease the tailheavy imbalance ratio needed to force pitch by heave. Perturbing the equations for heave varying as semi-rotary roll, an unswept wing of low enough dynamic imbalance ratio can start to flutter in light wind but stop and feather in storms. The dynamic imbalance can be reduced at large scale and low design windspeed where the gravity effect of static imbalance more safely forces pitch. Between starting and stopping, the amplitude ratio of pitch to roll drops, containing the rise with windspeed of the bending moment amplitude. [ABSTRACT FROM AUTHOR]

Abstract: Crop irrigation is a major consumer of energy. Only a few countries are self-sufficient in conventional non-renewable energy sources. Fortunately, there are renewable ones, such as wind, which has experienced recent developments in the area of power generation. Wind pumps can play a vital role in irrigation projects in remote farms. A methodology based on daily estimation balance between water needs and water availability was used to evaluate the feasibility of the most economic windmill irrigation system. For this purpose, several factors were included: three-hourly wind velocity (W 3h, m/s), flow supplied by the wind pump as a function of the elevation height (H, m) and daily greenhouse evapotranspiration as a function of crop planting date. Monthly volumes of water required for irrigation (Dr, m3/ha) and in the water tank (Vd, m3), as well as the monthly irrigable area (Ar, ha), were estimated by cumulative deficit water budgeting taking in account these factors. An example is given illustrating the use of this methodology on tomato crop (Lycopersicon esculentum Mill.) under greenhouse at Ciego de Ávila, Cuba. In this case two different W 3h series (average and low wind year), three different H values and five tomato crop planting dates were considered. The results show that the optimum period of wind-pump driven irrigation is with crop plating in November, recommending a 5m3 volume tank for cultivated areas around 0.2ha when using wind pumps operating at 15m of height elevation. [Copyright &y& Elsevier]

Here we explore light absorption by snowpack containing black carbon (BC) particles residing within ice grains. Basic considerations of particle volumes and BC/snow mass concentrations show that there are generally 0.05-109 BC particles for each ice grain. This suggests that internal BC is likely distributed as multiple inclusions within ice grains, and thus the dynamic effective medium approximation (DEMA) (Chýlek and Srivastava, 1983) is a more appropriate optical representation for BC/ice composites than coated-sphere or standard mixing approximations. DEMA calculations show that the 460 nm absorption cross-section of BC/ice composites, normalized to the mass of BC, is typically enhanced by factors of 1.8-2.1 relative to interstitial BC. BC effective radius is the dominant cause of variation in this enhancement, compared with ice grain size and BC volume fraction. We apply two atmospheric aerosol models that simulate interstitial and within-hydrometeor BC lifecycles. Although only ~2% of the atmospheric BC burden is cloud-borne, 71-83% of the BC deposited to global snow and sea-ice surfaces occurs within hydrometeors. Key processes responsible for within-snow BC deposition are development of hydrophilic coatings on BC, activation of liquid droplets, and subsequent snow formation through riming or ice nucleation by other species and aggregation/accretion of ice particles. Applying deposition fields from these aerosol models in offline snow and sea-ice simulations, we calculate that 32-73% of BC in global surface snow resides within ice grains. This fraction is smaller than the within-hydrometeor deposition fraction because meltwater flux preferentially removes internal BC, while sublimation and freezing within snowpack expose internal BC. Incorporating the DEMA into a global climate model, we simulate increases in BC/snow radiative forcing of 43-86 %, relative to scenarios that apply external optical properties to all BC. We show that snow metamorphism driven by diffusive vapor transfer likely proceeds too slowly to alter the mass of internal BC while it is radiatively active, but neglected processes like wind pumping and convection may play much larger roles. These results suggest that a large portion of BC in surface snowpack may reside within ice grains and increase BC/snow radiative forcing, although measurements to evaluate this are lacking. Finally, previous studies of BC/snow forcing that neglected this absorption enhancement are not necessarily biased low, because of application of absorption-enhancing sulfate coatings to hydrophilic BC, neglect of coincident absorption by dust in snow, and implicit treatment of cloud-borne BC resulting in longer-range transport. [ABSTRACT FROM AUTHOR]

The research done for this article is following the elaboration of a moldable model on the actual economic context, in which there are considered continuous learning elements on facts and commercial niches, evaluating a business starting from causality diagram and structuring its processes. Analyzing the evolution of a business and on the market in which they are deploying their activity through quantitative and qualitative measurement methods focused on trends. Testing hypotheses and business suppositions that are the main engine of theory focused on planning, a model of creating a strategic management process that will be developed in this article. [ABSTRACT FROM AUTHOR]

Multi-criteria analysis in decision making quantifies both objective and subjective factors. In the selection of the pumping system for irrigation objective factors are usually considered but subjective factors are overlooked. The selection of the best alternative may even get changed if we consider the subjective factors along with objective factors. In this paper analysis has been done to modify the Brown-Gibson Plant location model to consider the objective factors and Analytical Hierarchical Process (AHP) is applied to consider the subjective factors in the decision process of selecting wind pumping system, in place of traditional diesel and electric pumping system or in place of manual pump. To compare a wind pumping system with diesel and electric pump, a locally made wind pumping system is considered and annual useful amount of energy is calculated by writing a Computer Program. The combined analysis of both factors has shown that wind pumps get highest preference. [ABSTRACT FROM AUTHOR]

Abstract: The combined efficiency of the components determines overall system performance in electric wind pumping systems. We evaluated a system composed of a 3kW wind generator feeding a battery bank of 48V/880Ah by means of a non-controlled 6-pulse rectifier. Connected to this battery bank was a 1.5kW inverter that generated 220V at 50Hz, which powers a 1.1kW single-phase electric pump. At the University of Concepcion, Chile, energy losses in each electrical component was determined using a data collection system configured to measure electrical variables in real time. The electrical power generated by the wind generator for different wind speeds averaged 38% lower than the power curve provided by the manufacturer. Electromechanical tests performed in a lab showed the operation efficiency of the electric generator of the wind turbine averaged 80%. This information, along with the electrical power output, and the wind velocity measured during field operation allowed us to determine the rotor’s power coefficient Cp , which had a maximum value of 35%. For the stored energy components measured data indicated that the rectifier, the battery bank, and the inverter operated with average efficiencies of 95%, 78% and 86% respectively. The combined component efficiencies showed a maximum of 17% of the wind energy would be available for water pumping. Since a large amount of wind energy was dissipated during the energy conversion process, new configurations should be analyzed that could avoid such losses in wind pumping systems. [ABSTRACT FROM AUTHOR]

A theoretical formulation of the operation of wind pumps is proposed, including the starting and stopping behaviour. The paper defines a wind pump form of Froude number as the basic dimensionless parameter of the system. The influence of the turbine's power levels at low tipspeed ratios on the system performance is studied. The study is based on theoretical analysis and confirmed by experimental findings on the behaviour of constant-torque machines. [ABSTRACT FROM AUTHOR]

Abstract: This paper is devoted to analytical modelling and numerical simulation of the so-called pumping kite wind generator whose operating principle is to mechanically drive a groundbased electric generator using tethered kites. On the basis of the refined crosswind motion law, the mathematical model of steady crosswind motion of the tethered kite is constructed. Necessary conditions for optimality of the mean mechanical power functional are derived. Optimal control of the tether length rate is studied for the cases of open-loop and closed-loop figure-of-eight trajectories. The performance coefficient of the pumping kite wind generator is introduced. Simple formulas for the mechanical power output are obtained. [Copyright &y& Elsevier]

The Harries family came to Kenya in 1904 and settled on land north of Nairobi, where they farm until the present day. Whilst flying for a Christian Medical Mission in the early 1970's, Mike discovered how crucial water was to the prevention of Trachoma. This got him thinking about the problem of reliable water supplies in remote areas, and windpower seemed to be an appropriate solution. With various development partners the Harries family has spent the last 30 years, developing a wind range of Windpumps under the Trade Mark "Kijito", and have to date installed 400 windpumps, of which 100 have been exported. The design does not use castings or gears, and is therefore suitable for manufacture in a relatively simple workshop in developing countries. With the current situation in fossil fuel supply BHEL are now seriously considering venturing into power generation, as well as a dual purpose Kijito and going back to grinding grain with wind. [ABSTRACT FROM AUTHOR]

Classic thermal management solutions for microelectronics are becoming inadequate and there is an increasing need for fundamentally new approaches. Electrohydrodynamic ionic wind pumps, also known as electrostatic fluid accelerators (EFA), have the potential for becoming a critical element in electronics thermal management solutions. As the EFA field continues to evolve, developing new EFA-based technologies will require accurate models that can help predict pump performance metrics, such as air velocity profile, back pressure, and cooling effectiveness. Many previous modeling efforts only account for electrostatic interactions. For truly accurate modeling, however, it is important to include effects of fluid dynamics and space charge diffusion in charge transport. The modeling problem becomes especially challenging for the design and optimization of EFA devices with greater complexity and smaller dimensions. This paper presents a coupled- physics finite element model (FEM) using a complete EFA. charge transport model including charge diffusion and fluid dynamic effects. A cantilever EFA structure is modeled and analyzed for forced convection cooling. Numerical modeling predicts maximum air velocities of approximately 4 m/s and a maximum convection heat transfer coefficient of 280 W/(m2K) for the cantilever EFA structure investigated. Preliminary experimental results for a microfabricated cantilever EFA device for forced convection cooling are also discussed [ABSTRACT FROM AUTHOR]

The increased availability of wind power is beginning to cause utilities problems as engineers attempt to synchronise the power grid. Utilities have tended to ignore the operational aspects of wind power until there are commercial pressures to take positive action. The nature of these pressures may be understood by considering the classic problem of unit commitment. [ABSTRACT FROM AUTHOR]

Abstract: This article describes the currently operational version of the low-technology wind pump of high efficiency, as presented in [Valdès L-C, Raniriharinosy K. Low technical wind pumping of high efficiency. Renewable Energy 24 (2001) 275–301]. The pump, made entirely of wood and using roller bearings for the rotating links and a rubber membrane for water tightness, is of a more modular conception. Its manufacture is slightly more complicated, but its dimensioning has been greatly simplified, its reliability significantly improved and the use of wind energy optimised. [Copyright &y& Elsevier]

Presents a method for predicting the output of mechanical wind pumps in India. Calculation of wind pump discharges; Estimation of the energy produced by the rotor in wind regimes; Characteristics of wind pumps.

Presents information on a study which assessed the performance of wind-powered irrigation management using mechanical and electrical windpumps in Bushland, Texas. Analysis of the wind-speed data; Performance study of the two windpumps; Estimated windpump discharge; Capacity of reservoirs; Significance of the daily windpump output.

An ionic or electric wind is a bulk air movement induced by electrohydrodynamic (EHD) phenomena in a gas discharge. Because they are silent, low power, respond rapidly, and require no moving parts, ionic wind devices have been proposed for a wide range of applications, ranging from convection cooling and food drying to combustion management. The past several decades have seen the area grow tremendously leading to a number of new actuation strategies and devices that can be incorporated into various applications. In this review, we discuss the physics of ionic winds and recent developments of the past five years that have pushed the field forward, focusing on the development on bulk air-moving devices we term EHD pumps. We then highlight the ongoing challenges with transitioning ionic wind technologies to the market place, from issues that affect robustness to practical implementation, and point to areas where future research could have an impact on the field. [ABSTRACT FROM AUTHOR]