Journal articles: 'Hydraulic Benefits'

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Kang, Wen Long, and Yang Wang. "Diagnosis and Management of the Polluted Hydraulic Oil." Advanced Materials Research 619 (December 2012): 447–50. http://dx.doi.org/10.4028/www.scientific.net/amr.619.447.

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Hydraulic technology is widely applied in various fields of national economy, so the performance of hydraulic system directly influences all aspects of the economic benefits. The status of hydraulic oil is important for the working performance of hydraulic system.The pollution of hydraulic oil is a reason，which causes the fault of hydraulic system And it will cause the failure of system and loss of benefit. So it's very important that the fault of hydraulic system be diagnosed and treated. This paper introduces hydraulic oil pollution and the method of diagnosing and treating it.

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Kaufman, Martin M., and Matthew Wurtz. "HYDRAULIC AND ECONOMIC BENEFITS OF DOWNSPOUT DWERSION." Journal of the American Water Resources Association 33, no. 2 (April 1997): 491–97. http://dx.doi.org/10.1111/j.1752-1688.1997.tb03527.x.

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Yan, Chao. "Remanufacturing and Benefits Analysis of Construction Machinery Hydraulic Valves." Applied Mechanics and Materials 401-403 (September 2013): 2266–70. http://dx.doi.org/10.4028/www.scientific.net/amm.401-403.2266.

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Lots of hydraulic valves lose efficacy every year because of the complex mechanism of construction machinery, bad working conditions and changeable objects. These invalid hydraulic valves were melted down in the oven and then reused. However, the additional value of valves is wasted, and it will consume a lot of resources. The remanufacturing industry, which is becoming more and more mature, can solve this problem. The hydraulic valve can be remanufactured by recollection and using professional technology. Here is an introduction of failure modes and remanufacturing process of hydraulic valve, and also a deep analysis to the benefits of economy, resources and environment. It turned out that remanufacturing can restore the function of the invalid hydraulic valve and shorten the production cycle. It also can save costs by 55%, save resources by 85% and save material by 90%.

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Pothukuchi, Kameshwari, Melissa Arrowsmith, and Natalie Lyon. "Hydraulic Fracturing." Journal of Planning Literature 33, no. 2 (October 26, 2017): 155–70. http://dx.doi.org/10.1177/0885412217733991.

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Food system and energy planners have given scant attention to the impacts on agrifood systems of a particular form of energy production—fracking—and its implications for planning and regulation. Impacts include those related to water availability and quality; land quality, use, and value; wildlife; labor costs; infrastructure and services; and the implications of boom and bust dynamics of these for the sustainability of agriculture and food systems. Planning is challenged by competing frames of economic and environmental benefits, lack of capacity, power imbalances, and sometimes state policy. This review maps research on these linkages, identifies elements of successful planning, and offers directions for future research.

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Lozano-Baez, Sergio Esteban, Yamileth Domínguez-Haydar, Simone Di Prima, Miguel Cooper, and Mirko Castellini. "Shade-Grown Coffee in Colombia Benefits Soil Hydraulic Conductivity." Sustainability 13, no. 14 (July 12, 2021): 7768. http://dx.doi.org/10.3390/su13147768.

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Secondary tropical forests and coffee agroforestry systems contain fewer trees than native forests but can positively impact soil hydrological functions, such as water infiltration compared to the pasture land that they replace. However, for both land uses it remains in how far the soil hydraulic characteristics are comparable to that of native forest. Therefore, we investigated the saturated hydraulic conductivity (Ks) and some hydrophysical soil attributes in four land-use types: (i) a shade-grown coffee; (ii) a natural regenerated forest 15 years ago; (iii) a pasture; and (iv) a reference forest, in the municipality of La Jagua de Ibirico, César department, Colombia. We determined historical land use and conducted soil sampling, using the Beerkan method to determine the Ks values. We also measured canopy cover, vegetation height, diameter at breast height and total number of trees in the forest covers. Our results indicate that Ks values were similar for the coffee and the reference forest, reflecting the positive effect of trees on soil hydrological functioning in agroforestry systems. Our results suggest that 15 years of forest regeneration after land abandonment in Sub-Andean Forest, can improve the soil hydraulic attributes. Additionally, soil water repellency was observed for the reference forest soil.

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Kaykhosravi, Sarah, Karen Abogadil, Usman T. Khan, and Mojgan A. Jadidi. "The Low-Impact Development Demand Index: A New Approach to Identifying Locations for LID." Water 11, no. 11 (November 8, 2019): 2341. http://dx.doi.org/10.3390/w11112341.

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The primary goal of low impact development (LID) is to capture urban stormwater runoff; however, multiple indirect benefits (environmental and socioeconomic benefits) also exist (e.g., improvements to human health and decreased air pollution). Identifying sites with the highest demand or need for LID ensures the maximization of all benefits. This is a spatial decision-making problem that has not been widely addressed in the literature and was the focus of this research. Previous research has focused on finding feasible sites for installing LID, whilst only considering insufficient criteria which represent the benefits of LID (either neglecting the hydrological and hydraulic benefits or indirect benefits). This research considered the hydrological and hydraulic, environmental, and socioeconomic benefits of LID to identify sites with the highest demand for LID. Specifically, a geospatial framework was proposed that uses publicly available data, hydrological-hydraulic principles, and a simple additive weighting (SAW) method within a hierarchical decision-making model. Three indices were developed to determine the LID demand: (1) hydrological-hydraulic index (HHI), (2) socioeconomic index (SEI), and (3) environmental index (ENI). The HHI was developed based on a heuristic model using hydrological-hydraulic principles and validated against the results of a physical model, the Hydrologic Engineering Center-Hydrologic Modeling System model (HEC-HMS). The other two indices were generated using the SAW hierarchical model and then incorporated into the HHI index to generate the LID demand index (LIDDI). The framework was applied to the City of Toronto, yielding results that are validated against historical flooding records.

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Wilson, Adam. "All-Electric Subsea Well Brings Benefits vs. Traditional Hydraulic Technology." Journal of Petroleum Technology 70, no. 04 (April 1, 2018): 65–66. http://dx.doi.org/10.2118/0418-0065-jpt.

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COONEY, MARGARET M., and JUDITH B. WALKER. "Hydraulic resistance exercise benefits cardiovascular fitness of spinal cord injured." Medicine & Science in Sports & Exercise 18, no. 5 (October 1986): 522???525. http://dx.doi.org/10.1249/00005768-198610000-00005.

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Zhao, Zhenfeng, Shan Wang, Shuanlu Zhang, and Fujun Zhang. "Thermodynamic and energy saving benefits of hydraulic free-piston engines." Energy 102 (May 2016): 650–59. http://dx.doi.org/10.1016/j.energy.2016.02.018.

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Sunny, Iftekhar, Stewart Husband, Nick Drake, Kevan Mckenzie, and Joby Boxall. "Quantity and quality benefits of in-service invasive cleaning of trunk mains." Drinking Water Engineering and Science 10, no. 2 (July 6, 2017): 45–52. http://dx.doi.org/10.5194/dwes-10-45-2017.

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Abstract. Trunk mains are high risk critical infrastructure where poor performance can impact on large numbers of customers. Both quantity (e.g. hydraulic capacity) and quality (e.g. discolouration) of trunk main performance are affected by asset deterioration in the form of particle accumulation at the pipe wall. Trunk main cleaning techniques are therefore desirable to remove such material. However, little is quantified regarding the efficacy of different maintenance interventions or longer-term changes following such cleaning. This paper presents an assessment of quantity and quality performance of a trunk main system pre, post and for 12 months following cleaning using pigging with ice slurry. Hydraulic calibration showed a 7 times roughness height reduction after ice slurry pigging, evidencing substantially improved hydraulic capacity and reduced headloss. Turbidity response due to carefully imposed shear stress increase remained significant after the cleaning intervention, showing that relatively loose material had not been fully removed from the pipe wall. Overall the results demonstrate that cleaning by pigging with ice slurry can be beneficial for quantity performance, but care and further assessment may be necessary to realise the full quality benefits.

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Zakharov, Viacheslav, and Tatiana Minav. "Analysis of Field Oriented Control of Permanent Magnet Synchronous Motor for a Valveless Pump-Controlled Actuator." Proceedings 64, no. 1 (November 20, 2020): 19. http://dx.doi.org/10.3390/iecat2020-08491.

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Earlier research demonstrated that a pump-controlled hydraulic system combines the best properties of traditional hydraulics and electric intelligence. Thus, the new system has been proposed as a replacement for conventional valve-controlled systems, to improve the energy efficiency in non-road mobile machinery in particular. One of the pump-controlled systems can be realized via direct control of hydraulic pump/motor by varying speed of prime mover. Electric motor (EM) as a prime mover attract with higher efficiency (more than 90%) and a wide range of speed regulation. These advantages allow to improve the system efficiency and decrease the energy consumption in electric and hybrid non-road mobile machinery. Further EM's efficiency improvement can be achieved by using vector control systems, which provide rotor magnetic flux control proportionally to the shaft's speed. Considering all vector control’s benefits (high accuracy of speed control, smooth~start and smooth rotation of the motor in the entire frequency range, quick response to load changes, increased control range and accuracy of regulation), the electro-hydraulic systems and influence of electric part on hydraulic one is not investigated widely. Therefore, in this paper Field Oriented Control (FOC) is analyzed as One of the most perspective vector control systems for electro-hydraulic actuator application with a Permanent Magnet Synchronous Machine (PMSM) as a prime mover. In~this study, Direct-driven hydraulics (DDH) was considered as a study case. A detailed model of the PMSM control system with DDH was built in MATLAB/Simulink. The behavior of the DDH system was investigated by transient processes analysis of EM, pump, and cylinder in the normal and failure modes. The system demonstrates a difference between reference and simulated speed about 0.33% and 11.75% of average torque fluctuations. The behavior of the system in failure mode demonstrated multiple excesses of rated parameters.

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Kim, Hyo Gon, Jong Won Lee, Yong Ho Choi, Jeong Woo Park, and Jin Ho Suh. "Simulations and Experiments on the Force Control of Hydraulic Servo System for Hydraulic Robots." Applied Mechanics and Materials 826 (February 2016): 128–33. http://dx.doi.org/10.4028/www.scientific.net/amm.826.128.

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Because hydraulic actuator has higher power and force density, it is normally used in heavy load manipulator robots and industrial equipment which require high torque. Also, the hydraulic actuator is applied to underwater robots that need high performance maneuver in underwater operations. The force control has benefits to those kind of robots to ensure compliance with user or environment. However, the hydraulic actuator is difficult to control forces due to the non-linearity characteristic of the hydraulic servo system. In this paper, we propose a force control method with compensation of force derivative and natural velocity feedback. We also describe a method of applying it to the real system. In order to evaluate the effect of the proposed control method, the simulations and experiments were performed.

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Niraula, Abinab, Shuzhong Zhang, Tatiana Minav, and Matti Pietola. "Effect of Zonal Hydraulics on Energy Consumption and Boom Structure of a Micro-Excavator." Energies 11, no. 8 (August 10, 2018): 2088. http://dx.doi.org/10.3390/en11082088.

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This paper investigates the effect of extra weight caused by the Direct Driven Hydraulics (DDH) in a micro-excavator. These projects are investigating the implementation of zonal or decentralized hydraulics for non-road mobile machinery (NRMM) and stationary industrial applications. The benefit of DDH is the combination of electric and hydraulic technologies in a compact package compared to conventional hydraulics, which enables a reduction of potential leakage points, flexible tubing, and boosting of the system efficiency due to switching to direct pump control instead of a loss-generating conventional valve-based control. In order to demonstrate these benefits for the excavator case, this paper proposes a system model approach to assess and predict energy consumption of the zonal hydraulics approach implemented with DDH in various working cycles, complemented by a structural analysis. The finite element analysis utilized for this demonstrated that the extra weight and selected location of DDH units do not negatively affect the structure of the excavator. Simulation results demonstrated that the energy consumption is approximately 15% higher with extra weight added by the three DDH units. Although approximately 20% more regeneration energy is produced, taking into account the regeneration energy, the increases in energy consumption are about 12%.

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Li, Yan Pin, Xiao Qing Li, and Peng Fei Wang. "The Importance Role of WC Coat for Hydraulic Turbine Protection." Advanced Materials Research 129-131 (August 2010): 435–37. http://dx.doi.org/10.4028/www.scientific.net/amr.129-131.435.

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This article discussed the preserve effect of the WC-HVOF coating to hydraulic turbine based on the research of sand abrasion in hydropower stations on the upstream of Yellow River. At the same time the importance role of WC coat for Hydraulic turbine protection and the great economic benefits from reasonable utilization of WC-HVOF coating are also been discussed in this article, using Sanmenxia hydropower stations as an example. All these have important reference significance for the other similar stations to use WC-HVOF coating to protect the hydraulic turbines.

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Liu, Hong Yu. "Three Dimensions Construction Model and Finite Element Analysis of Hydraulic Support and Relevant Model." Advanced Materials Research 189-193 (February 2011): 4451–54. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.4451.

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Hydraulic support is an important equipment of coal mine production. Its design and manufacture level affects the safe production and economic benefits of coal mine directly. This paper took ZT6500/19.5/34 hydraulic support as an example. First, three dimensions solid models of the type simplified hydraulic support prototype and its 1:5 model were constructed by three dimensions construction model software SolidWorks. Then, three dimensions solid models were led in ANSYS software. Finally, the strength test of the type hydraulic support prototype and its 1:5 model were proceeded under base torsion working condition by ANSYS software. The relevant total displacement distribution rule and equivalent stress distribution rule of the type simplified hydraulic support prototype and its 1:5 model were found. The proportion relation of total displacement and equivalent stress between the type simplified hydraulic support prototype and its 1:5 model were confirmed. This provides an effective way of design and research hydraulic support.

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Fitz-Coy, Norman, Vivek Nagabhushan, and Michael T. Hale. "Benefits and Challenges of Over-Actuated Excitation Systems." Shock and Vibration 17, no. 3 (2010): 285–303. http://dx.doi.org/10.1155/2010/435740.

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This paper provides a comprehensive discussion on the benefits and technical challenges of controlling over-determined and over-actuated excitation systems ranging from 1-DOF to 6-DOF. The primary challenges of over-actuated systems result from the physical constraints imposed when the number of exciters exceeds the number of mechanical degree-of-freedom. This issue is less critical for electro-dynamic exciters which tend to be more compliant than servo-hydraulic exciters. To facilitate the technical challenges discussion, generalized methods for determining the drive output commands and the actuator input transform is presented. To further provide insights into the problem, over-actuated 1-DOF and 6-DOF examples are provided. Results are presented to support the discussions.

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Mowery, Ralph B., Dennis A. Teefy, and Neal C. Werner. "Cost, operational readiness, and environmental benefits for the reutilization of used hydraulic oil." Federal Facilities Environmental Journal 13, no. 3 (2002): 81–91. http://dx.doi.org/10.1002/ffej.10047.

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Hadimani *, Sharanagouda, Dr Nilesh Diwakar, Dr G. R. Selokar, and Dr B. Nageshwar Rao. "Design & Analysis of Dynamic Response in Hydrolic Equipment Working with Heavy Loads." International Journal of Engineering and Advanced Technology 10, no. 3 (February 28, 2021): 215–18. http://dx.doi.org/10.35940/ijeat.c2243.0210321.

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Hydraulic system has benefits over pneumatic or electric systems, especially when heavy loads are involved, or when very smooth and precise position or pressure control is required. Hydraulic actuators have several advantages including the fact that they produce less heat and electrical interference at the machine than do electric actuators. A simulation model of the support was established to determine the dynamic responses of the hydraulic support under dual impacts from its roof and shield beams, and the column and balance jack were replaced using a spring-damper system. Analysis of poses was performed and dynamic support responses were obtained.

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Bair, Russell T., Catalina Segura, and Christopher M. Lorion. "Quantifying the restoration success of wood introductions to increase coho salmon winter habitat." Earth Surface Dynamics 7, no. 3 (September 5, 2019): 841–57. http://dx.doi.org/10.5194/esurf-7-841-2019.

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Abstract. Large wood (LW) addition is often part of fish habitat restoration projects. However, there is limited information about the spatial–temporal variability in hydraulic changes after LW additions. We investigated reach-scale hydraulic changes triggered after the addition of LW that are relevant to juvenile coho salmon survival. We used Nays2DH, an unsteady two-dimensional flow model, to quantify the patterns and magnitudes of changes of stream velocity and shear stress in three alluvial gravel reaches. The study sites are located in low-gradient reaches draining 5 to 16 km2 in the Oregon Coast Range. Survivable habitat was characterized in terms of critical swim speed for juvenile coho and bed stability considering the critical shear stress required to mobilize the median bed particle size. Model predictions indicated that survivable habitat during bankfull conditions, measured as the area with velocity below the critical swim speed for juvenile coho, increased by 95 %–113 % after the LW restoration. Bed stability also increased between 86 % and 128 % considering the shear stress required to mobilize the median bed particle size. Model predictions indicated more habitat created in the larger site; however, considering that wood would move more frequently in this site there appears to be a trade-off between the timing and the resilience of restoration benefits. Overall, this study quantifies how the addition of LW potentially changes stream hydraulics to provide a net benefit to juvenile salmonid habitat. Our findings are applicable to stream restoration efforts throughout the Pacific Northwest.

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Kotzev, A., D. B. Cherchas, P. D. Lawrence, and N. Sepehri. "Generalized predictive control of a robotic manipulator with hydraulic actuators." Robotica 10, no. 5 (September 1992): 447–59. http://dx.doi.org/10.1017/s0263574700010651.

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SUMMARYThis paper presents some aspects of the behavior of hydraulically actuated heavy duty manipulators. This category of manipulators is used extensively in large resource based industries and any improvement in efficiency may result in major financial benefits. In this paper an adaptive control algorithm is used for a two rigid link manipulator driven by hydraulic actuators. The dynamic model of the manipulator is derived as well as the models of the hydraulic actuators including compliance, dead time and full dynamics of the servo valves. An adaptive control algorithm is considered since changes occur on-line in the system's parameters. The adaptive algorithm used is Generalized Predictive Control (GPC). The GPC uses a controlled autoregressive integrated moving average (CARIMA) type model and a cost function that minimizes a predicted future output error and future weighted control inputs to the plant, resulting in a sequence of future control increments. The procedure, in this work, does not separate the hydraulic actuator and the link dynamics into separate sub-systems, but controls them as one system. The changes in the system's parameters due to the hydraulics or the link dynamics can be estimated and the coefficients of the model adjusted without the necessity of identifying the exact cause of the changes.It was found in this work that the variations of the GPC control horizon can lead to faster response during transients and significantly reduced overshoot in the nonlinear hydraulic actuation system. An on-line change of the maximum output horizon is also introduced.This work shows the analysis and results of a two link manipulator with hydraulic actuators. It can be implemented on any hydraulically actuated manipulator with any number of links and actuators.Numerical simulations are performed on a Vax 3200 computer and the results are presented.

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Kučera, Marián, Zdeněk Aleš, Jan Mareček, and Pavel Máchal. "Effect of Contamination on the Lifetime of Hydraulic Oils and Systems." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 65, no. 4 (2017): 1205–12. http://dx.doi.org/10.11118/actaun201765041205.

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The extensions of service‑lives regarding hydraulic fluids is gaining prominence due to several considerations including environmental pollution, conservation of natural resources and the economic benefits associated with extended service‑life. The presented methods for testing the durability and oxidation stabilities of hydraulic fluids can be simultaneously used in two ways. Firstly for comparing different hydraulic biooils and for selecting more adequate oils with higher oxidation stabilities and longer service lifetimes and secondly for the development of a prognostic model for an accurate prediction of an oil’s condition and its remaining useful lifetime, which could help to extend the service life of the oil without concerns about damaging the equipment.

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Rakhimov, Оktyabr, Laylo Аshurova, and Fotima Artikbekova. "Hydraulic transport in small livestock farms." E3S Web of Conferences 274 (2021): 03003. http://dx.doi.org/10.1051/e3sconf/202127403003.

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The article highlights the advantages and benefits of pipeline transport of liquid feed mixtures on small pig farms, the device and the principle of operation and technical characteristics of the improved rotor pump developed by the authors of the article. Methods of experimental research to determine the concentration of feed mixtures, the influence of the shape of the separator on the performance characteristics, the required power and the flow of an improved pump are presented. The results of the experiments showed that one of the bottlenecks limiting the operation of rotary pumps on feed mixtures of increased concentration is the low suction capacity of the pump, that is, the design of the suction pipe of the pump, where an increase in resistance with an increase in the concentration of feed mixtures causes a breakdown of the operating mode and cavitation. To resolve this issue, we used a screw feeder installed in front of the pump suction nozzles. It was found that if the screw feeder provides excess pressure within (about, 0.25 ... 0.3) 105 Pa per suction cavity, the pump operates stably and reliably.

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Sedki, Imad, and Raymond Moore. "Patient evaluation of the Echelon foot using the Seattle Prosthesis Evaluation Questionnaire." Prosthetics and Orthotics International 37, no. 3 (October 8, 2012): 250–54. http://dx.doi.org/10.1177/0309364612458448.

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Background: The introduction of the Echelon prosthetic foot with a hydraulic self-aligning ankle adds improved adaptability to varied terrains and uneven walking surfaces. However, the specific indications for prescribing such components and the potential benefits are yet to be fully established. Case Description and Methods: Nine amputees including three bilateral amputees evaluated their standard prostheses using the Seattle Prosthesis Evaluation Questionnaire. They were then provided with Echelon feet, and they evaluated them after 4 weeks of use. Findings and Outcomes: Improved satisfaction in all categories of use in relation to the Echelon foot with the greatest increase reported by bilateral amputees. Conclusion: The use of prosthetic feet with hydraulic self-aligning ankle improves prosthetic users’ satisfaction in general with a particular benefit in bilateral amputees. Clinical relevance Establish the clinical impact and user satisfaction after using Echelon feet in prosthetic users with different levels of amputations.

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Yang, Jiao. "Fracturing Proppant Evaluation and Economic Optimization in Daqing Oilfield." Defect and Diffusion Forum 394 (August 2019): 63–67. http://dx.doi.org/10.4028/www.scientific.net/ddf.394.63.

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Fracturing proppant is an important material for hydraulic fracturing, and its performancehas an important impact on the fracturing effect and the fracturing life of oil and gas wells. On thepremise of satisfying the reservoir reconstruction requirement, optimizing the proppant with the besteconomic benefit can reduce the cost of the fracturing operation. The flow conductivity and brokenrate of common proppants are tested to obtain the performance boundaries. Based on the proppantevaluation, according to the selection method, the optimal proppant type for different formationpressures can be selected to maximize economic benefits.

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Lee, Songbog, and Sehong Min. "Improvement of Velocity Change Based on Increase in Fire Water Demand Capacity." Journal of the Korean Society of Hazard Mitigation 20, no. 5 (October 31, 2020): 65–72. http://dx.doi.org/10.9798/kosham.2020.20.5.65.

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Recently, sprinkler systems have been designed based on hydraulic calculations to determine the diameter of the water supply pipe. However, the hydraulic calculation currently applied in the underground parking lot area of apartments is generally applied for economic benefits obtained by reducing the pipe size specified in the National Fire Safety Codes Installation Standard. However, the Standard overlooks the nature of hydraulic calculation. Therefore, this study examines and analyzes the flow rate, pressure, and flow rate relationship obtained by supplying a capacity higher than the water supply-demand capacity required for the hydraulic calculation as the water supply capacity of the fire pump. Accordingly, through suggesting an improvement in pressure-reducing valve installation, the firefighting system separation, pipe-diameter change application, the engineer's skill, water supply capacity, and water demand capacity could be matched to uniformly supply the minimum pressure and flow rate for each sprinkler head. It is expected that it can be improved in a direction that satisfies the hydraulic calculation standards.

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Grindal, Robert J., and Tony K. Griffin. "Effect of hydraulic milking on milking performance, teat condition and lipolysis." Journal of Dairy Research 56, no. 1 (February 1989): 45–53. http://dx.doi.org/10.1017/s0022029900026200.

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SummaryThe term ‘hydraulic milking’ describes a new milking concept in which liner movement is restricted and the liner is flooded with milk beneath the teat. This condition, achieved with a multi-valve claw without air admission to the cluster, reduced milking time by 26% and increased milk flow rate by 20%. Four experiments describe the discovery of hydraulic milking and investigate its potential using equal or different levels of vacuum in the milkline and pulseline. Benefits from hydraulic milking include decreased lipolysis (≤36%) and milk foam (75%), improved teat condition and a high degree of protection against machine-induced infections. Evidence of increased milk yield is inconclusive. Cluster removal is impeded by hydraulic milking and the multi-valve cluster requires modification to facilitate the process. Pulsation characteristics and vacuum levels developed for conventional milking appear adequate for hydraulic milking. Unorthodox vacuum conditions may be needed, however, to exploit fully this novel milking concept.

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Jastrzębski, Grzegorz, Paweł Szczepaniak, and Michał Jóźko. "Issues Related To Troubleshooting Of Avionic Hydraulic Units." Journal of KONBiN 30, no. 1 (December 1, 2014): 59–73. http://dx.doi.org/10.2478/jok-2014-0015.

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Abstract The paper outlines workflows associated with troubleshooting of avionic hydraulic systems with detailed description of the troubleshooting algorithm and classification of diagnostic signals provided by avionic hydraulic systems and their subassemblies. Attention is paid to measurement sequences for diagnostic signals from hydraulic systems, circuits and units. Detailed description is dedicated to an innovative design of a troubleshooting device intended for direct measurements of internal leaks from avionic hydraulic units. Advantages of the proposed measurement method are summarized with benefits from use of the presented device and compared against the methods that are currently in use. Subsequent phases of the troubleshooting process are described with examples of measurement results that have been acquired from subassemblies of hydraulic systems of SU-22 aircrafts currently in service at Polish Air Forces with consideration given to cases when the permissible threshold of diagnostic signals were exceeded. Finally, all results from investigations are subjected to thorough analysis.

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Molinari, Daniela, Susanna Dazzi, Edoardo Gattai, Guido Minucci, Giulia Pesaro, Alessio Radice, and Renato Vacondio. "Cost–benefit analysis of flood mitigation measures: a case study employing high-performance hydraulic and damage modelling." Natural Hazards 108, no. 3 (June 4, 2021): 3061–84. http://dx.doi.org/10.1007/s11069-021-04814-6.

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AbstractThis paper shows a detailed, advanced procedure to implement cost–benefit analyses (CBAs) in order to assess the effectiveness of flood mitigation measures. The town of Lodi (North of Italy) has been selected as a case study for the research work, as it was hit by a large flood in 2002 for which several data are available. In order to compute the benefits, in terms of avoided damage with the mitigation measure in place, micro-scale damage models developed within the Flood-IMPAT + project were used. The great amount of input data for such models comes from results of a two-dimensional river modelling, for what concern the hazard parameters, and from open-source database, to evaluate the vulnerability and the exposure of the hit area. The research highlights that technological-advanced, high-performance hydraulic models allow taking into account a variety of hazard scenarios, with reasonable computational time, supporting the proper accounting of the probabilistic nature of risk in CBAs. Nonetheless, such high-resolution tools support the implementation of micro-scale damage assessment models, which can provide information on the distribution of benefits in the investigated area, increasing the effectiveness of CBAs for policy making.

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Carpenter, Chris. "Natural-Gas-Foam Fluid Reduces Water Needed for Fracture Stimulations." Journal of Petroleum Technology 73, no. 06 (June 1, 2021): 56–57. http://dx.doi.org/10.2118/0621-0056-jpt.

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This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 201450, “Reducing the Volume of Water Needed For Hydraulic Fracturing by Using Natural-Gas-Foamed Stimulation Fluid,” by Raj Malpani, SPE, Chris Daeffler, and Sandeep Verma, SPE, Schlumberger, et al., prepared for the 2020 SPE Annual Technical Conference and Exhibition, originally scheduled to be held in Denver, Colorado, 5–7 October. The paper has not been peer reviewed. Using natural-gas (NG) -foam fracturing fluids reduces the enormous water requirements for stimulation by as much as 60 to 80% and poses benefits for productivity in water-sensitive formations. The study outlined in the complete paper aims to characterize hydraulic-fracture geometry and quantify the expected production when using an NG-foam fracturing fluid. Using validated models, the authors provide a comparative analysis to determine the advantages of using NG foams relative to conventionally used slickwater, linear gel, and crosslinked fluid. NG-Foam Fluids Although foamed fluids were first used in the 1960s, the use of nitrogen (N2) and carbon dioxide (CO2) foams has not been widely practiced because of cost, complexity, and unproven production benefits. The use of NG-foam fracturing fluid is not widespread either, but this study attempts to identify specific regions and reservoirs where the use of these fluids may lead to economic and long-term production benefits. The authors write that using NG foams is likely to provide long-term sustainable benefits in areas where water procurement and disposal costs are high, where natural gas may be available from a central processing facility through pipelines, and where the reservoir is relatively shallow and contains clay-bearing minerals. This work is inspired by a program sponsored by the US Department of Energy to investigate NG as an alternative to N2 and CO2 in foamed fracturing fluids. Initially, the project focused on identifying a thermodynamic path-way to use NG obtained from producing wells and processing plants. The study later extended into laboratory-scale experiments to measure NG-foam-fluid rheology, which was found to be comparable to foams based on N2 and CO2. The first step in the work flow is to build a static geological model to capture the reservoir description. The subsequent step is to use the rock characterization to simulate the induced hydraulic fractures. The hydraulic-fracture simulator also predicts the proppant distribution and its conductivity and treating pressure. The simulated treating pressure is matched with observed pressure during stimulation treatment to calibrate the hydraulic-fracture model. The hydraulic fractures are then gridded in the static geological model to generate the reservoir model for flow modeling. This is a critical step in the process because the static model is linked to the dynamic simulator without losing the details of the hydraulic fractures. The reservoir simulator is used to match the historical production performance to calibrate the reservoir model and forecast future production profiles. This hydraulic-fracture modeling, followed by the flow-modeling process, is repeated for various pumping schedules and recipes to perform a sensitivity analysis, which is detailed in the complete paper.

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Sovacool, Benjamin K. "Cornucopia or curse? Reviewing the costs and benefits of shale gas hydraulic fracturing (fracking)." Renewable and Sustainable Energy Reviews 37 (September 2014): 249–64. http://dx.doi.org/10.1016/j.rser.2014.04.068.

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Soliman, Enas M., M. I. Saleh, and S. A. Hammad. "Benefits of Treated Rice Straw on Soil Hydraulic Properties under Saline-Sodic Irrigation Water." Journal of Soil Sciences and Agricultural Engineering 10, no. 7 (July 1, 2019): 415–21. http://dx.doi.org/10.21608/jssae.2019.53687.

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Takeshima, N., M. M. Islam, M. E. Rogers, M. Narita, Y. Yamada, and A. Okada. "PHYSIOLOGICAL BENEFITS OF HYDRAULIC RESISTANCE MACHINES VERSUS ELASTIC BAND EXERCISES IN OLDER JAPANESE ADULTS." Medicine & Science in Sports & Exercise 34, no. 5 (May 2002): S250. http://dx.doi.org/10.1097/00005768-200205001-01401.

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Wheeler, David, Margo MacGregor, Frank Atherton, Kevin Christmas, Shawn Dalton, Maurice Dusseault, Graham Gagnon, et al. "Hydraulic fracturing – Integrating public participation with an independent review of the risks and benefits." Energy Policy 85 (October 2015): 299–308. http://dx.doi.org/10.1016/j.enpol.2015.06.008.

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Li, Xiu Lei, and Yong Wu. "Gravitational Potential Energy Recovery and Recycle of Rotary Drilling Rig Kelly Bar." Applied Mechanics and Materials 635-637 (September 2014): 159–62. http://dx.doi.org/10.4028/www.scientific.net/amm.635-637.159.

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In order to improve the economic benefits of tunneling to rotary drilling rig ,in this paper ,the rotary drilling rig main winch hydraulic system was improved ,by increasing an hydro pneumatic accumulator storage and releasing gravitational potential energy of kelly bar ,as well as increasing reversing motor and the main winch motor to form a hydraulic transformer .So ensured the high pressure when the energy release and reduced the rotary drilling rig engine power ,what’s more ,this system’s feasibility had been verified by theoretical calculation .

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Jusoh, Mohd Afifi, Mohd Zamri Ibrahim, Muhamad Zalani Daud, Aliashim Albani, and Zulkifli Mohd Yusop. "Hydraulic Power Take-Off Concepts for Wave Energy Conversion System: A Review." Energies 12, no. 23 (November 27, 2019): 4510. http://dx.doi.org/10.3390/en12234510.

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Ocean wave energy is one of the most abundant energy sources in the world. There is a wide variety of wave energy conversion systems that have been designed and developed, resulting from the different ways of ocean wave energy absorption and also depending on the location characteristics. This paper reviews and analyses the concepts of hydraulic power take-off (PTO) system used in various types of wave energy conversion systems so that it can be a useful reference to researchers, engineers and inventors. This paper also reviews the control mechanisms of the hydraulic PTO system in order to optimise the energy harvested from the ocean waves. Finally, the benefits and challenges of the hydraulic PTO system are discussed in this paper.

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Cyr, Robert Y., and Paul Chiasson. "Modeling subsoil drainage systems for urban roadways." Canadian Journal of Civil Engineering 26, no. 6 (December 1, 1999): 799–809. http://dx.doi.org/10.1139/l99-048.

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Water infiltration and seepage in a roadway infrastructure is modeled from a cross section design of a residential street used by the City of Moncton (Department of Engineering). Field hydraulic conductivity measurements necessary for the modeling are also presented. Benefits of having a subsoil drainage systems (perforated drainage pipe and drainage mat) are well demonstrated. Some drainage problems caused by insufficient hydraulic conductivity, segregation, and limits on gradation curves for the gravel base foundation, as specified by the City of Moncton, are also discussed.Key words: roadway design, subsoil drainage, seepage modeling, field permeability measurements.

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dos Santos, Mauricio, Wilson C. Rodrigues, Ana Paula S. de Matos Dias, Lirio Schaeffer, and Arão de Matos Dias. "Design and Development of Compaction Tools for Powder Metallurgy." Materials Science Forum 899 (July 2017): 341–46. http://dx.doi.org/10.4028/www.scientific.net/msf.899.341.

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The aim of this work is to analyse options of different powder metallurgy tools design with upper punch adapted with springs and its benefits with regards green density of the parts compacted in hydraulic press. Crack of the parts also were observed.

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Lee, Seungyub, Sangmin Shin, David R. Judi, Timothy McPherson, and Steven J. Burian. "Criticality Analysis of a Water Distribution System Considering Both Economic Consequences and Hydraulic Loss Using Modern Portfolio Theory." Water 11, no. 6 (June 12, 2019): 1222. http://dx.doi.org/10.3390/w11061222.

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This study introduces an approach using Modern Portfolio Theory (MPT) to consider hydraulic resilience and economic consequence resilience of a water distribution system (WDS) to identify critical assets. ECLIPS (Economic Consequence Linked to Interruption in Providing Service), a way to represent loss of water provision as economic loss, is used to measure economic consequence following a reduction of WDS functionality. The approach is demonstrated using a hypothetical WDS and tested for pipe breakage and replacement scenarios using EPANET hydraulic simulations. First, the correlation between hydraulic resilience and economic consequence resilience was investigated to assess differences between two resilience measures for identifying pipe’s criticality for replacement. The results confirmed the two resilience measures exhibited differing responses (covariance = 0.2), suggesting that use of both would provide complementary insight. Results of the MPT analysis identified the benefits of balancing hydraulic and economic consequence resilience measures to yield lower risk. This study provides a practical approach to incorporate economic consequence into planning, design, and research applications identifying critical WDS assets.

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van der Vlist, M. J., S. S. H. Ligthart, and M. Zandvoort. "The replacement of hydraulic structures in light of tipping points." Journal of Water and Climate Change 6, no. 4 (March 19, 2015): 683–94. http://dx.doi.org/10.2166/wcc.2015.094.

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In many delta areas hydraulic structures are key elements in water management strategies for fresh water supply and flood risk management. Adaptation of delta areas to changing climatological and societal conditions will be in pace with the renovation and replacement of these hydraulic structures. Since hydraulic structures are prone to deterioration, their performance diminishes over time. Changes in society, the economy, and the physical environment can also alter the functionality of structures, or have an impact on their performance. Although faced with deterioration and exogenous changes, timing of replacement is essential because replacing too early leads to insufficient use of invested capital, while replacing too late leads to loss of societal benefits. This article explores the timing of replacement using adaptation tipping points. We indicate three drivers – deterioration, biophysical change, and socio-economic change – that determine the moment in time when replacement becomes necessary. Moreover, we conclude that for determining the moment of replacement, at the very least, the objectives, maintenance and operations of hydraulic structures need to be taken into account. This exploration is illustrated with the task of replacing seven hydraulic structures in the River Meuse.

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Vladimirov, Victor, Thomas Simoner, and Ioan Bica. "Relining of pipe systems: conditions, benefits and application through case-study." Ovidius University Annals of Constanta - Series Civil Engineering 19, no. 1 (December 20, 2017): 7–14. http://dx.doi.org/10.1515/ouacsce-2017-0001.

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Abstract Relining is one of the best alternatives available today for pipe system rehabilitation. This trenchless solution is particularly interesting for urban agglomerations, as a smaller diameter pipe is pushed or pulled through the old pipeline. Relining creates a leak-tight “pipe within a pipe” system, which is as good as new in both structural and hydraulic terms. Relining can be performed with both circular and special, non-circular (NC) profiles. The latter is especially advantageous for the rehabilitation of old sewers, many of which were constructed in a variety of ovoid-like shapes. This paper presents the typical steps that are performed for pipeline rehabilitation with non-circular profiles, as well as an applied case study (a project implemented in the city of Würzburg in Germany).

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Boano, Fulvio, Alice Caruso, Elisa Costamagna, Luca Ridolfi, Silvia Fiore, Francesca Demichelis, Ana Galvão, Joana Pisoeiro, Anacleto Rizzo, and Fabio Masi. "A review of nature-based solutions for greywater treatment: Applications, hydraulic design, and environmental benefits." Science of The Total Environment 711 (April 2020): 134731. http://dx.doi.org/10.1016/j.scitotenv.2019.134731.

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Huerta, Nicolas J., Kirk J. Cantrell, Signe K. White, and Christopher F. Brown. "Hydraulic fracturing to enhance injectivity and storage capacity of CO2 storage reservoirs: Benefits and risks." International Journal of Greenhouse Gas Control 100 (September 2020): 103105. http://dx.doi.org/10.1016/j.ijggc.2020.103105.

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Hilpert, Markus, Bruce D. Marsh, and Peter Geiser. "The radiator-enhanced geothermal system: Benefits of emulating a natural hydrothermal system." Interpretation 4, no. 4 (November 1, 2016): SR35—SR48. http://dx.doi.org/10.1190/int-2016-0032.1.

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We have developed a novel enhanced geothermal system (EGS) called radiator EGS (RAD-EGS). This system attempts to emulate naturally occurring hydrothermal systems by creating a vertically oriented heat exchanger or vane in the deep subsurface, mimicking a radiator in an internal combustion engine. Water is injected at the bottom of the vane and produced on the top. We propose to build the RAD-EGS in hot sedimentary aquifers (HSAs) with high-permeability vane(s) created in the plane defined by [Formula: see text] and [Formula: see text] (vertical). We have evaluated 3D heat-transfer simulations to better understand the fluid and heat flows that may occur in RAD-EGSs. The simulations account for subsurface heterogeneity including the presence of underlying basement rock, an overlying confining layer, and an ambient hydraulic gradient, which causes background groundwater flow. Our simulations indicate that our induced upward flow in the vane significantly prolongs the lifetime of RAD-EGS when compared with downward flow because hydraulic short circuiting is avoided. Within the vane, convection may occur, and its onset is analyzed in terms of a characteristic Rayleigh number. A critical aspect of RAD-EGS, therefore, is that thermal recharge does not rely solely on heat conduction from the surrounding wall rock, which is typical for EGS built in hot dry rock (HDR). Instead, recharge is also due to heat advection through the surrounding water-saturated aquifer, substantially prolonging the lifetime of the thermal reservoir. Moreover, fluid losses as typical for EGS built in HDR do not occur. It is also possible that cold water injected at the bottom of the vane may sink into deeper rock layers, which displaces hot water from the surrounding aquifer into the RAD-EGS. We suggest that mimicking a natural hydrothermal system is a successful EGS strategy via RAD-EGS.

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Walczak, Natalia. "Operational Evaluation of a Small Hydropower Plant in the Context of Sustainable Development." Water 10, no. 9 (August 22, 2018): 1114. http://dx.doi.org/10.3390/w10091114.

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Proper design of hydrotechnical structures should meet the basic principles of sustainable development, i.e., the investment should be designed and made in technical terms, in accordance with the applicable standards and regulations, provide certain economic benefits and guarantee the absence of environmental hazards. The article examines the work of a Small Hydropower Plant (SHP) in Jaracz in technical and hydraulic terms. It also provides the analysis of the effect of changes in parameters such as water head, flow rate velocity, and shape of trash rack bars on expected SHP profits. The assessment of hydraulic performance consisted of investigating the impact of reduced flow rate and water head on power output and energy production. The analyses were carried out for the Francis turbine installed in the facility. Since the loss of channel capacity is shaped by plant debris accumulated on trash racks, the hydraulic performance assessment was extended to include the analysis of the species and weight composition of such accumulation on fine trash racks located in the inlet channel. Field research involved collecting organic material from the growing season (spring, summer) and post-growing season (autumn). Technical conditions were developed on the basis of the current technical condition of the inlet channel; there were also made simulations of its deteriorating state, as well as its impact on the received energy and economic benefits.

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Mergl, Václav, Zdravko Pandur, Jan Klepárník, Hrvoje Kopseak, Marin Bačić, and Marijan Šušnjar. "Technical Solutions of Forest Machine Hybridization." Energies 14, no. 10 (May 13, 2021): 2793. http://dx.doi.org/10.3390/en14102793.

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The paper deals with the characteristics of three different types of power train hybridization of forest logging machines and with the benefits of reducing environmental impacts by comparing new technology with more conventional, older technology. New hybridization options that could be implemented in forestry machines are also discussed. The paper divides a hybrid solution into three classes based on the energy used in the system of hybridization. First is an electro-hybrid system that uses an electric motor and battery or different storage device. The second, a hydraulic hybrid system, is a solution with a hydraulic accumulator, hydraulic motor, and pump. The third system is a combination of the electro-hybrid and hydraulic-hybrid system. The current technical and technological development of hybrid drive systems, as well as their components, has led to significant improvements in drive performance and thus better performance of the new generation of forest vehicles. Improved energy efficiency using hybrid propulsion systems in forest vehicles would result in a significant reduction in greenhouse gas emissions and possibly lower maintenance costs.

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Li, Jianxiong, Shiming Dong, Wen Hua, Xiaolong Li, and Xin Pan. "Numerical Investigation of Hydraulic Fracture Propagation Based on Cohesive Zone Model in Naturally Fractured Formations." Processes 7, no. 1 (January 8, 2019): 28. http://dx.doi.org/10.3390/pr7010028.

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Complex propagation patterns of hydraulic fractures often play important roles in naturally fractured formations due to complex mechanisms. Therefore, understanding propagation patterns and the geometry of fractures is essential for hydraulic fracturing design. In this work, a seepage–stress–damage coupled model based on the finite pore pressure cohesive zone (PPCZ) method was developed to investigate hydraulic fracture propagation behavior in a naturally fractured reservoir. Compared with the traditional finite element method, the coupled model with global insertion cohesive elements realizes arbitrary propagation of fluid-driven fractures. Numerical simulations of multiple-cluster hydraulic fracturing were carried out to investigate the sensitivities of a multitude of parameters. The results reveal that stress interference from multiple-clusters is responsible for serious suppression and diversion of the fracture network. A lower stress difference benefits the fracture network and helps open natural fractures. By comparing the mechanism of fluid injection, the maximal fracture network can be achieved with various injection rates and viscosities at different fracturing stages. Cluster parameters, including the number of clusters and their spacing, were optimal, satisfying the requirement of creating a large fracture network. These results offer new insights into the propagation pattern of fluid driven fractures and should act as a guide for multiple-cluster hydraulic fracturing, which can help increase the hydraulic fracture volume in naturally fractured reservoirs.

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Cherivirala, Y. K., H. Lyu, H. A. Alhowri, and A. Babakhani. "Wirelessly Powered Microchips for Mapping Hydraulic Fractures." SPE Journal 24, no. 04 (March 11, 2019): 1830–38. http://dx.doi.org/10.2118/194491-pa.

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Summary The onset of the era of internet of things and artificial intelligence comes with the ever-growing demand for self-sustaining and efficient sensors. Sensors based on complementary metal oxide semiconductors (CMOSs) have attracted significant attention in the implementation of distributed sensor systems for a vast number of applications because of their economical and complex integration benefits. In this work, we report CMOS-based energy-harvesting chips as wireless nodes for mapping hydraulic fractures during the shale gas extraction process. The CMOS chips are tested in a custom benchtop core-holder chamber that emulates a downhole environment. An induction coil, sized at 5 × 5 mm, connected to a custom CMOS chip, is used as a receiver inside the core holder to harvest electromagnetic (EM) energy transmitted by an external antenna. On the basis of the custom core-holder experiment, it is shown that encapsulated CMOS chips are able to harvest EM energy and thereby operate wirelessly. The receiver has a resonance frequency of 198 MHz. The CMOS chip is equipped with an integrated power management unit (PMU), energy-harvesting unit, and a signal-generation block. The CMOS chip inside the chamber produces an output signal with a frequency proportional to the harvested power. By measuring the frequency of the output signal produced by the chip, we are able to localize the chips within the rock inside the custom core holder.

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Reventós, F., L. Batet, C. Llopis, C. Pretel, and I. Sol. "Thermal-Hydraulic Analysis Tasks for ANAV NPPs in Support of Plant Operation and Control." Science and Technology of Nuclear Installations 2008 (2008): 1–13. http://dx.doi.org/10.1155/2008/153858.

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Thermal-hydraulic analysis tasks aimed at supporting plant operation and control of nuclear power plants are an important issue for the Asociación Nuclear Ascó-Vandellòs (ANAV). ANAV is the consortium that runs the Ascó power plants (2 units) and the Vandellòs-II power plant. The reactors are Westinghouse-design, 3-loop PWRs with an approximate electrical power of 1000 MW. The Technical University of Catalonia (UPC) thermal-hydraulic analysis team has jointly worked together with ANAV engineers at different levels in the analysis and improvement of these reactors. This article is an illustration of the usefulness of computational analysis for operational support. The contents presented were operational between 1985 and 2001 and subsequently changed slightly following various organizational adjustments. The paper has two different parts. In the first part, it describes the specific aspects of thermal-hydraulic analysis tasks related to operation and control and, in the second part, it briefly presents the results of three examples of analyses that were performed. All the presented examples are related to actual situations in which the scenarios were studied by analysts using thermal-hydraulic codes and prepared nodalizations. The paper also includes a qualitative evaluation of the benefits obtained by ANAV through thermal-hydraulic analyses aimed at supporting operation and plant control.

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Tsige-Tamirat, Haileyesus, and Luca Ammirabile. "Study on the Use of Hydride Fuel in High-Performance Light Water Reactor Concept." Science and Technology of Nuclear Installations 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/965274.

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Hydride fuels have features which could make their use attractive in future advanced power reactors. The potential benefit of use of hydride fuel in HPLWR without introducing significant modification in the current core design concept of the high-performance light water reactor (HPLWR) has been evaluated. Neutronics and thermal hydraulic analyses were performed for a single assembly model of HPLWR with oxide and hydride fuels. The hydride assembly shows higher moderation with softer neutron spectrum and slightly more uniform axial power distribution. It achieves a cycle length of 18 months with sufficient excess reactivity. At Beginning of Cycle the fuel temperature coefficient of the hydride assembly is higher whereas the moderator and void coefficients are lower. The thermal hydraulic results show that the achievable fuel temperature in the hydride assembly is well below the design limits. The potential benefits of the use of hydride fuel in the current design of the HPLWR with the achieved improvements in the core neutronics characteristics are not sufficient to justify the replacement of the oxide fuel. Therefore for a final evaluation of the use of hydride fuels in HPLWR concepts additional studies which include modification of subassembly and core layout designs are required.

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Crawford, Mark. "Fracturing Rocks to Unlock New Oil." Mechanical Engineering 135, no. 12 (December 1, 2013): 24–29. http://dx.doi.org/10.1115/1.2013-dec-1.

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This article discusses various uses and benefits of hydraulic fracturing technology in the field of oil industry. Engineers continue to increase hydraulic fracturing efficiency by developing better multistage stimulation systems. These systems enable treatment of many intervals along a horizontal wellbore with a minimum number of pull-outs, or even in a single continuous operation. Many key advances in drilling and hydrofracturing have resulted from sophisticated modeling programs. Mechanical engineers play key roles in many aspects of hydrofracturing, especially the design of better down-hole tools, new materials, and improved numerical models. With the advances in modeling and real-time measurement, operators can deliver just the right type of fracking pressure, exactly where they want it, and repeat the process as needed, either in the same well, one that parallels it, or one that radiates out from the same central drill pad. The experts feel that if the world wishes to fully use its oil-and-gas resources, it will go hand-in-hand with hydraulic fracturing.

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Journal articles on the topic 'Hydraulic Benefits'

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