RESEARCH ON DISCHARGE CIRCUIT OF ELECTRO-HYDRAULIC POWER IMPULSE WATER JETS

2012 ◽  
Vol 11 (06) ◽  
pp. 1240043
Author(s):  
ZHAOHUI WANG ◽  
QUANJIE GAO ◽  
WEI WANG ◽  
ZHENFANG LIAO
Keyword(s):  
Mechanical Energy ◽  
Surface Cleaning ◽  
Discharge Circuit ◽  
Energy Utilization ◽  
Electrode Spacing ◽  
Maximum Pressure ◽  
Hydraulic Power ◽  
Water Jets ◽  
Material Forming ◽  
Spacing Parameter

Electro-hydraulic power impulse water jets can convert the shock wave generated in the liquid by discharging into mechanical energy, and it has been widely used in material forming, surface cleaning, pipeline dirt cleaning and ore breaking process. Compared with the traditional high pressure water jets, the energy utilization of electro-hydraulic power impulse water jets is up to 80% while the water consumption is reduced by 40–55%. This paper has taken electro-hydraulic power impulse water jets as the research object, employed obtaining the maximum pressure of compression impulse matrix surface as the research goal, studied in depth the equivalent discharge circuit, characteristic equation and the relationship between the electrical parameters of the electro-hydraulic power impulse discharge circuit and built the calculation method of the voltage, the inductance, the capacitance and the electrode spacing parameter of electro-hydraulic power impulse water jets discharge circuit. So, it will provide important theoretical basis for further studies of electro-hydraulic power impulse technology and the existing water jets device.

scholarly journals Numerical Evaluation and Experimental Test on a New Giant Magnetostrictive Transducer with Low Heat Loss Design

Micromachines ◽  
2021 ◽  
Vol 12 (11) ◽  
pp. 1397
Author(s):  
Zhuan Bai ◽  
Zonghe Zhang ◽  
Ju Wang ◽  
Xiaoqing Sun ◽  
Wei Hu
Keyword(s):  
Heat Loss ◽  
Temperature Rise ◽  
Magnetic Energy ◽  
Mechanical Energy ◽  
Electric Energy ◽  
Energy Utilization ◽  
Element Analysis ◽  
Excessive Heat ◽  
Excitation Coil ◽  
Magnetostrictive Transducer

Giant magnetostrictive transducer with micro and nano precision has a wide application prospect in the field of remote sensing. However, excessive heat loss of components could generate during the energy conversion and transfer from electric energy to magnetic energy, and magnetic energy to mechanical energy, thereby affecting its long-term service and also reducing energy utilization. In this paper, a new magnetostrictive transducer is proposed and its excitation coil, internal and external magnetic circuit are optimized from the perspective of reducing heat loss. With the help of theoretical and finite element analysis, the response law between key parameters and heat loss of key components are summarized, which provides a basis for reducing heat loss. Finally, according to the optimization scheme, the prototype is processed, and the temperature rise and dynamic output performance of the transducer are tested by constructing an experimental setup. The results show that the transducer has a low temperature rise and good frequency response characteristics, which can provide support for long-time precise actuation on-orbit.

A SIMULATION STUDY OF ENERGY UTILISATION IN A VARIABLE LINK LENGTH 3 DOF REVOLUTE ARTICULATED MANIPULATOR

2015 ◽  
Vol 76 (4) ◽  
Author(s):  
Wan Sulaiman Wan Mohamad ◽  
Zulkifli Mohamed ◽  
Zainoor Hailmee Solihin ◽  
Kamrol Amri Mohamed
Keyword(s):  
Simulation Study ◽  
Energy Method ◽  
Mechanical Energy ◽  
Minimum Energy ◽  
Average Energy ◽  
Energy Utilization ◽  
Link Length ◽  
Manipulator Link ◽  
Point To Point

Determination of manipulator link lengths is one of the important criteria in robotic design. The purpose of this study is to find the minimum energy utilization for a 3 DOF revolute articulated manipulator to perform certain point-to-point task by varying the link lengths of the manipulator. The lengths of the second and third link of the developed manipulator can be varied accordingly. The investigation of energy for different link length combinations is carried out theoretically. In the simulation, the work-energy method is constituted in order to determine the average mechanical energy of the manipulator. The simulation shows that, different trajectory of motions results in different link length combinations that could give optimum average energy utilization. Results of the simulations shows that, improvement of mechanical energy utilization could be achieved by having variable link length of manipulator rather than having fixed length of manipulator’s arms. 

Economic and Technical Efficiency of High Performance Abrasive Waterjet Cutting

2010 ◽  
Author(s):  
Axel Henning ◽  
Peter Liu ◽  
Carl Olsen
Keyword(s):  
Technical Efficiency ◽  
High Performance ◽  
Abrasive Waterjet ◽  
Hydraulic Power ◽  
Water Jets ◽  
Path Control ◽  
Manufacturing Process Chain ◽  
High Level ◽  
Mechanical Machining ◽  
Cutting Path

Abrasive water jets have recently become a popular tool for mechanical machining. With its great advantages of geometric and material flexibility and its ability to cut hard-to-machine materials the technology is quickly spreading throughout many industries. With this near net-shape production becomes feasible, while significantly reducing the time necessary for secondary operations like programming, clamping, or tool changing. This allows a significant optimization of the overall manufacturing process chain. In this paper different approaches to increase the economic and technical efficiency of cutting with abrasive water jets are analyzed. Experimental analysis of the speed of abrasive particles show that the kinetic power of the particles mainly depends on the hydraulic power of the waterjet. Merely increasing the pressure of the jet did not yield any improvement in its acceleration capability. To obtain the most effective cutting performance a high level of hydraulic power through large nozzles should therefore be utilized. Additionally, recent advancements in cutting path control software have proven to significantly decrease the total ‘time to product’ and to increase the precision of the part. Those improvements in both software control and cutting power enable abrasive water jets to become an integral part of many industrial manufacturing processes. This will widen the scope of possible applications of this innovative and promising technology.

Ultrasound and Doppler

2011 ◽  
Author(s):  
Patrick Magee ◽  
Mark Tooley
Keyword(s):  
Soft Tissues ◽  
Cell Function ◽  
Safety Issue ◽  
Mechanical Energy ◽  
Longitudinal Direction ◽  
Maximum Pressure ◽  
Ultrasound Wave ◽  
Low Energies ◽  
The Difference ◽  
Human Hearing

Ultrasound has many uses in areas of medicine associated with anaesthesia. It is used for imaging, visualisation of needle and catheter positioning, therapy and, together with the Doppler effect, for measurement of flow velocity. Real-time information can be obtained with ease, and with the low energies used, diagnostic equipment exposures are not thought to be a safety issue, either for the operator or the patient. Ultrasound is a form of mechanical energy that consists of high frequency vibrations at frequencies above human hearing range (> 20 kHz) and up to frequencies in the tens of MHz range. The frequencies used are dependent on issues such as the penetration and resolution required. It is thought that low intensity ultrasound passes through living tissue without altering tissue function. Higher energy can produce heating and cavitation, both of which can alter cell function. Ultrasound is generated by electrically inducing a deformation in a piezoelectric crystal, which compresses and decompresses the medium to which it is coupled at a rate equal to the frequency of the driving voltage. The pressure changes travel through the medium in a longitudinal direction and the distance between the points of maximum pressure, or compression, is known as the wavelength. Figure 10.2 shows the relationship between the period of the wave and the wavelength. The length of this distance is dependent on the elasticity (compressibility) and the density of the medium, and the delay between the movement of adjacent particles in the medium. As shown in the figure, the wavelength (λ) and the transmission frequency (f) are related to the propagation velocity c by c = f λ. The magnitude of the wave is the difference between the maximum and minimum pressure values. The wave propagates by movement of particles: it cannot travel in a vacuum and it does not ionise the medium through which it travels. The propagation of an ultrasound wave is not constant throughout the body. Various parts allow the passage of the wave at different velocities. Also the wave is attenuated differently by the various tissue types. For example, in soft tissues the ultrasound wave has a velocity of between 1460 and 1630 m s−1 whereas in bone it is 2700–4100 m s−1.

Recent Developments in the Use of Hydraulic Power

1940 ◽  
Vol 143 (1) ◽  
pp. 129-141
Author(s):  
H. C. Town
Keyword(s):  
Civil Engineering ◽  
Power Production ◽  
Maximum Pressure ◽  
Power Development ◽  
Hydraulic Power ◽  
Pumping Station ◽  
Engineering Development ◽  
Recent Developments ◽  
Power Operation ◽  
Hydraulic Operation

Hydraulic power development may be divided into two groups, first, one in which mechanical and civil engineering developments combine to use natural forces for power production, and second, the phase of hydraulic power development which it is proposed to consider, namely that appertaining to mechanical production and automotive traction. Until recent times, no phase of engineering development has remained comparatively stationary for so long a period as that of power operation by hydraulic means. It is true that there has always been a field where the characteristics of hydraulic power were essential, but in the more recent drawing and stamping industries, hydraulic operation was unable to compete until developments in collateral fields removed all disadvantages. Prominent amongst the developments to this end, has been the introduction of the variable-delivery pump to each machine, as against the central pumping station. These self-contained units are available with a normal maximum pressure of 1,000 lb. per sq. in., but in certain cases no less than 5,000 lb. per sq. in. can be obtained.

scholarly journals Hydraulic power take off system for wave energy utilization

2021 ◽  
Vol 1032 ◽  
pp. 012030
Author(s):  
R Velichkova ◽  
M Pushkarov ◽  
R A Angelova ◽  
I Simova ◽  
D Markov ◽  
...  
Keyword(s):  
Wave Energy ◽  
Energy Utilization ◽  
Hydraulic Power

A discussion on deformation of solids by the impact of liquids, and its relation to rain damage in aircraft and missiles, to blade erosion in steam turbines, and to cavitation erosion - Some aspects of rock cutting by high speed water jets

1966 ◽  
Vol 260 (1110) ◽  
pp. 295-310 ◽  
Keyword(s):  
Pressure Distribution ◽  
High Speed ◽  
Frictional Heating ◽  
Water Jet ◽  
Short Exposure ◽  
Maximum Pressure ◽  
Steam Turbines ◽  
Target Plate ◽  
Water Jets ◽  
The Impact

When rocks are cut in coal mines by steel picks, frictional heating sometimes causes ignition of methane; high speed water jets may provide a method of cutting which is free from this hazard. A high speed water jet emerging from a nozzle slows down with increasing distance from the nozzle and breaks up into water drops. Studies were made of the behaviour of water jets: in most of the experiments the jets were produced by pressures of 600 atm., but some results are given of experiments at pressures up to 5000 atm. The jets were examined by short exposure optical photography with several different methods of illumination (parallel transmitted, diffuse, and schlieren) and by X-ray photography. In order to find out how the jet velocity decays with distance from a nozzle, and to compare nozzle designs, a target plate containing a hole smaller than the jet diameter was placed so that the jet impinged at right angles on to it, and the target plate was moved until the maximum pressure at the hole was found: this was measured for different distances from the nozzle. Nozzle shapes suggested in literature for minimizing jet dispersion were studied and an empirical investigation of a variety of nozzle shapes was carried out. Several nozzle shapes were found which gave good results, i.e. the maximum pressure on the target plate was half the pump pressure at a distance of about 350 nozzle diameters. In many cutting applications the first stage in the process would be the impingement of a water jet on a surface at right angles. The initial cutting would depend upon the stress distribution within the target, which in turn would depend upon the pressure distribution produced by the water jet on the surface. A theory is given of the pressure distribution on the target plate, which predicts that the pressure will fall to zero at about 2.6 jet radii: this was found to be in good agreement with experiments. Preliminary studies were made of the penetration of several types of rock by water jets of velocities up to about 1000 m/s (pressures about 5000 atm). It was found that a 1 mm diameter jet drills a cylindrical hole about 5 mm in diameter. The pressure that the water jet produces at the bottom of such holes was measured and shown to fall off to about one-tenth of the nozzle pressure at a hole depth of about 4 cm.

Uphill and level walking of a three-dimensional biped quasi-passive walking robot by torso control

Robotica ◽  
2014 ◽  
Vol 34 (3) ◽  
pp. 483-496 ◽  
Author(s):  
Ying Cao ◽  
Soichiro Suzuki ◽  
Yohei Hoshino
Keyword(s):  
Energy Efficiency ◽  
Mechanical Energy ◽  
Three Dimensional ◽  
Energy Utilization ◽  
Walking Robots ◽  
Utilization Rate ◽  
Walking Robot ◽  
Energy Transformation ◽  
Passive Walking ◽  
Level Walking

SUMMARYPassive walking robots can walk on a slight downward slope powered only by gravity. We propose a novel control strategy based on forced entrainment to stabilize a three-dimensional quasi-passive walking robot in uphill and level walking by using torso control in the frontal plane and synchronization of lateral motion with swing leg motion. We investigated the robot's walking energy efficiency, energy transformation, and transfer in simulation. The results showed that the proposed method is effective and energy-efficient for uphill and level walking. The relationship between energy utilization rate of actuation and energy efficiency of the robot was revealed, and mechanical energy transformation and transfer were characterized.

Biogas availability and its energy use in combined wastewater treatment plants (CWWTP)

2011 ◽  
Vol 6 (2) ◽  
Author(s):  
A. Meneses ◽  
D. L. Vargas ◽  
J. M. Grosso ◽  
A. Deeb ◽  
W. Wergara
Keyword(s):  
Activated Sludge ◽  
Energy Demand ◽  
Energy Use ◽  
Mechanical Energy ◽  
Anaerobic Treatment ◽  
Energy Utilization ◽  
Municipal Sewage ◽  
Operational Conditions ◽  
Carbon Sequestration Potential ◽  
Sequestration Potential

CWWTP are sanitation facilities formed by the coupling of an aerobic post-treatment (i.e. activated sludge, extended aeration, etc.) with a primary anaerobic treatment (i.e. UASB). In these combined arrangements, usually biogas produced in the UASB units is used to drive mechanical energy for aeration requirements in the secondary treatment (i.e. Activated Sludge, AS). Quality of effluents from CWWTP is similar to those from AS processes but combined treatments could become completely self-sufficient in energy consumption. In this manner, CWWTP improve the carbon-sequestration potential in the sanitation sector by increasing the capture of methane-rich biogas and its energy utilization. This study show how effluent quality parameters and energy demand in the AS unit can be influenced by control, sludge external recirculation and aeration strategies. Modelling and simulation tests, have allowed identifying operational conditions for potential energy savings and rational use of the biogas energy available in a full-scale CWWTP treating municipal sewage.

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