scholarly journals IMPROVING PRINCIPLES OF ELECTRIC ENERGY PULSE TRANSFORMATION INTO HIGH-FREQUENCY MECHANICAL ENERGY USING CAPACITIVE METHOD

2019 ◽  
Vol 2019 (6) ◽  
pp. 18-24 ◽  
Author(s):  
O.N. Petrishchev ◽  
◽  
K.L. Nozdrachova ◽  
G.M. Suchkov ◽  
R.P. Mygushchenko ◽  
...  
Keyword(s):  
High Frequency ◽  
Mechanical Energy ◽  
Electric Energy ◽  
Energy Pulse ◽  
Capacitive Method

scholarly journals Hydrodynamic constraints on the energy efficiency of droplet electricity generators

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Antoine Riaud ◽  
Cui Wang ◽  
Jia Zhou ◽  
Wanghuai Xu ◽  
Zuankai Wang
Keyword(s):  
Energy Efficiency ◽  
Kinetic Energy ◽  
Total Energy ◽  
Viscous Dissipation ◽  
Shear Force ◽  
Mechanical Energy ◽  
Electric Energy ◽  
The Past ◽  
Viscous Shear ◽  
Impingement Velocity

AbstractElectric energy generation from falling droplets has seen a hundred-fold rise in efficiency over the past few years. However, even these newest devices can only extract a small portion of the droplet energy. In this paper, we theoretically investigate the contributions of hydrodynamic and electric losses in limiting the efficiency of droplet electricity generators (DEG). We restrict our analysis to cases where the droplet contacts the electrode at maximum spread, which was observed to maximize the DEG efficiency. Herein, the electro-mechanical energy conversion occurs during the recoil that immediately follows droplet impact. We then identify three limits on existing droplet electric generators: (i) the impingement velocity is limited in order to maintain the droplet integrity; (ii) much of droplet mechanical energy is squandered in overcoming viscous shear force with the substrate; (iii) insufficient electrical charge of the substrate. Of all these effects, we found that up to 83% of the total energy available was lost by viscous dissipation during spreading. Minimizing this loss by using cascaded DEG devices to reduce the droplet kinetic energy may increase future devices efficiency beyond 10%.

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.

scholarly journals Comparison of Two Single Stage Low-Pressure Rotary Lobe Expander Geometries in Terms of Operation

Energies ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 4512
Author(s):  
Michalina Kurkus-Gruszecka ◽  
Piotr Krawczyk
Keyword(s):  
Cfd Simulation ◽  
Mechanical Energy ◽  
Electric Energy ◽  
Low Pressure ◽  
Single Stage ◽  
Small Scale ◽  
Operational Parameters ◽  
Data Simulation ◽  
Time Step ◽  
Geometry Model

In the article the computational fluid dynamics (CFD) simulation and calculated operational parameters of the single stage low-pressure rotary lobe expander compared with the values obtained from a different geometry simulation are presented. Low-pressure rotary lobe expanders are rotary engines that use a compressed gas to produce mechanical energy, which in turn can be converted into another form, i.e., electric energy. Currently, expanders are used in narrow areas, but have a large potential in the energy production from gases of low thermodynamic parameters. The first geometry model was designed on the basis of an industrial device and validated with the empirical data. Simulation of the second geometry was made based on a validated model in order to estimate the operational parameters of the device. The CFD model included the transient simulation of compressible fluid in the geometry changing over time and the rotors motion around two rotation axes. The numerical model was implemented in ANSYS CFX software. After obtaining simulation results in the form of parameters monitors for each time step, a number of calculations were performed using a written code analysing the CFD program output files. The article presents the calculation results and the geometries comparison in terms of work efficiency. The research indicated that the construction of the device on a small scale could cause a significant decrease in the aforementioned parameter, caused by medium leaks in the expander clearances.

scholarly journals Maximum power point tracking in photovoltaic systems

2019 ◽  
Vol 28 ◽  
pp. 01021
Author(s):  
Grażyna Frydrychowicz-Jastrzębska
Keyword(s):  
Block Diagram ◽  
Mechanical Energy ◽  
Electric Energy ◽  
Energy Conversion Efficiency ◽  
Maximum Power ◽  
Maximum Efficiency ◽  
Maximum Power Point ◽  
Point Tracking ◽  
Power Point Tracking ◽  
Power Point

The subject of the analysis was the optimisation of interoperation between the photovoltaic battery (PV) and DC motor, which drives a fan, with respect to the maximum efficiency of conversion of the electric energy into mechanical energy. Based on the block diagram, a mathematical model of this circuit was developed to ensure the mutual matching between the Maximum Power Point (MPP) of the battery and the receiver operation point. A computer simulation of the battery characteristics was conducted taking into account the changing MPP location on the characteristic vs. changes in solar radiation and temperature. The issue was considered for the optimal motor excitation coefficient, both changing and averaged in time. The energy conversion efficiency was determined for selected PV modules, as well as time.

Study on Fault Diagnosis of Gear Transmission which is Based on ADAMS

2012 ◽  
Vol 215-216 ◽  
pp. 812-816
Author(s):  
Shi Ming Wang ◽  
Xian Zhu Ai ◽  
Chao Lv ◽  
Li Na Ma
Keyword(s):  
Time Domain ◽  
Mechanical Energy ◽  
Electric Energy ◽  
Image Data ◽  
Real Data ◽  
Sampling Theorem ◽  
Drive Gear ◽  
Ocean Wave Energy ◽  
Shannon Sampling Theorem ◽  
Simulation Parameters

Introduced a transmission system of a new oscillation buoy ocean wave energy generation device, the system can transform the mechanical energy into electric energy. A pair of gear model was built by SOLIDWORKS, the parameter is just the same as the real data, then imported the model into ADAMS. Under the same simulation parameters, two experiments were done, one engaged without failure, the other engaged with one broken tooth of drive wheels. Calculated TIME and STEPS by Shannon sampling theorem, simulated the marker point’s acceleration of the drive gear, then obtain image data of time domain and frequency domain, after analyzed, found this method has a significant meaning to practice.

scholarly journals Cellular Polyolefin Composites as Piezoelectric Materials: Properties and Applications

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2698
Author(s):  
Ewa Klimiec ◽  
Halina Kaczmarek ◽  
Bogusław Królikowski ◽  
Grzegorz Kołaszczyński
Keyword(s):  
Integrated Circuits ◽  
Piezoelectric Materials ◽  
Mechanical Energy ◽  
Constant Electric Field ◽  
Electric Energy ◽  
High Sensitivity ◽  
Human Motion ◽  
Piezoelectric Polymers ◽  
High Durability ◽  
Mineral Fillers

Piezoelectric polymers characterized by flexibility are sought for applications in microelectronics, medicine, telecommunications, and everyday devices. The objective of this work was to obtain piezoelectric polymeric composites with a cellular structure and to evaluate their usefulness in practice. Composites based on polyolefins (isotactic-polypropylene and polyethylene) with the addition of aluminosilicate fillers were manufactured by extrusion, and then polarized in a constant electric field at 100 V/µm. The content of mineral fillers up to 10 wt% in the polymer matrix enhances its electric stability and mechanical strength. The value of the piezoelectric coefficient d33 attained ~150 pC/N in the range of lower stresses and ~80 pC/N in the range of higher stresses, i.e., at ~120 kPa. The materials exhibited high durability in time, therefore, they can be used as transducers of mechanical energy of the human motion into electric energy. It was demonstrated that one shoe insert generates an energy of 1.1 mJ after a person walks for 300 s. The miniaturized integrated circuits based on polyolefin composites may be applied for the power supply of portable electronics. Due to their high sensitivity, they can be recommended for measuring the blood pulse.

Topology Optimization Design of Implantable Energy Harvesting Device

2011 ◽  
Vol 55-57 ◽  
pp. 498-503
Author(s):  
Bin Zheng ◽  
Liang Ping Luo
Keyword(s):  
Topology Optimization ◽  
Energy Harvesting ◽  
Optimization Design ◽  
Mechanical Energy ◽  
Electric Energy ◽  
Structure Design ◽  
Mems Devices ◽  
Sensors And Actuators ◽  
Piezoelectric Energy ◽  
Piezoelectric Structure

When designing implantable biomedical MEMS devices, we must provide electric power source with long life and small size to drive the sensors and actuators work. Obviously, traditional battery is not a good choice because of its large size, limited lifetime and finite power storage. Living creatures all have non-electric energy sources, like mechanical energy from heart beat and pulse. Piezoelectric structure can convert mechanical energy to electric energy. In the same design condition, the more electric energy is generated, the better the piezoelectric structure design. This paper discusses the topology optimization method for the most efficient implantable piezoelectric energy harvesting device. Finally, a design example based on the proposed method is given and the result is discussed.

O PROCESSO DE LICENCIAMENTO AMBIENTAL DE USINAS HELIOTÉRMICAS (CONCENTRATED SOLAR POWER – CSP): CONSIDERAÇÕES SOBRE SUA SIMPLIFICAÇÃO

2017 ◽  
Vol 32 (3) ◽  
pp. 248
Author(s):  
Marcelo Lampkowski ◽  
Odivaldo José Seraphim ◽  
Anselmo José Spadotto
Keyword(s):  
Solar Radiation ◽  
Solar Power ◽  
Mechanical Energy ◽  
Thermal Power ◽  
Electric Energy ◽  
Concentrated Solar Power ◽  
Power Cycles ◽  
Adoption And Implementation ◽  
High Incidence ◽  
Environmental Licensing

Empreendimentos baseados em tecnologias de energia solar concentrada (Concentrated Solar Power - CSP), também chamada de solar-térmica ou heliotérmica, fazem uso de sistemas de concentração da radiação solar para obtenção de quantidades significativas de fluido a altas temperaturas para aplicação em ciclos térmicos de potência. Em usinas CSP, o calor do sol é captado e armazenado para, depois, ser transformado em energia mecânica e, por fim, em eletricidade. O calor recolhido aquece um líquido (fluido térmico) que passa por um receptor. Esse líquido armazena o calor e serve para aquecer a água dentro da usina e gerar vapor. A partir daí, o vapor gerado movimenta uma turbina e aciona um gerador, produzindo, assim, energia elétrica. No Brasil, apesar do alto índice de radiação solar direta incidente, ainda são escassos os projetos envolvendo a energia heliotérmica e acredita-se que alguns dos fatores que dificultam a adoção e a implementação destas tecnologias no país estão relacionados à complexidade do processo de licenciamento ambiental para construção e operação de usinas CSP e à ausência de uma legislação ambiental específica para empreendimentos baseados na heliotermia. Este artigo se propôs a apresentar os principais aspectos da legislação existente em relação à impactos ambientais e aos processos para a obtenção das licenças ambientais, relacionando-os com as características de usinas CSP. Com base na análise dos requisitos para os procedimentos de licenciamento levantados, foram desenvolvidas propostas para o estabelecimento de diretrizes de licenciamento que são essenciais para o desenvolvimento do mercado CSP no Brasil.PALAVRAS-CHAVE: Energias renováveis, energia solar concentrada, legislação vigente. THE CONCENTRATED SOLAR POWER (CSP) ENVIRONMENTAL LICENSING PROCESS: CONSIDERATIONS ABOUT ITS SIMPLIFICATIONABSTRACT: Plants based on Concentrated Solar Power (CSP) technologies, also called solar-thermal or heliothermal, make use of solar radiation concentration systems to obtain significant quantities of fluid at high temperatures for application in thermal power cycles. The sunlight is captured and stored. Then it is converted into mechanical energy and finally into electricity. The collected heat heats up a liquid (thermal fluid) that passes through a receiver. This liquid stores the heat and serves to heat the water inside the plant and generate steam. From there, the steam moves a turbine and drives a generator, thus producing electric energy. In Brazil, despite the high incidence of direct solar radiation, projects involving heliothermic energy are still scarce and it is believed that some of the factors that hinder the adoption and implementation of these technologies Brazil are related to the complexity of the environmental licensing process for construction and operation of CSP plants and also the absence of a specific environmental legislation for CSP projects. This paper proposes to present the main aspects of the existing legislation in relation to the environmental impacts and the processes to obtain the environmental licenses, relating them to the characteristics of CSP plants. Based on the analysis of the requirements for the licensing procedures raised, proposals were developed for the establishment of licensing guidelines that are essential for the development of the Brazilian CSP market.KEYWORDS: Renewable energies, concentrated solar power, current legislation

Phenomena Occurring during the Electro-Dynamic Forming of Non-Ferrous Pipe Elements

2011 ◽  
Vol 177 ◽  
pp. 23-35 ◽  
Author(s):  
Andrzej Kot
Keyword(s):  
Magnetic Field ◽  
Magnetic Flux ◽  
Energy Conversion ◽  
Pulse Magnetic Field ◽  
Mechanical Energy ◽  
Electric Energy ◽  
Flux Variation ◽  
Formed Product ◽  
Physical Phenomena

The paper presents description of physical phenomena arising during the process of electrodynamic forming by means of axisymetric inductors generating pulse magnetic field. Presented material shows the way for determination of pressures acting on non-ferrous pipe elements with an assumption of magnetic flux variation character in system. The paper describes also stages of energy conversion from electric energy of capacitors discharge into mechanical energy of pressure forming semi-finished product. The knowledge about presented phenomena allow to predict final shape of formed product during free forming by electrodynamic method.

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