MHD generator of electrical energy working on the gasification products of lignites

Abstract A magnetohydrodynamic (MHD) generator is a device that generates electrical energy through the interaction between a conductive fluid and a magnetic field. This method of direct energy conversion allows the use of a renewable energy source such as solar energy and represents an alternative to tackle the greenhouse effect. This paper presents the development of an MHD solar generator, which is constituted by a solar thermal system and an MHD cell. The solar thermal system consists of a set of tubes with copper fins, connected in parallel and placed inside of a 1 m2 panel. In which, an electrolytic mixture of H2O and NaCl at 20% vol. was introduced as a working fluid. In order to increase the kinetic energy of the fluid, the panel was exposed to solar radiation, where it reached temperatures above 373 K and pressures above 96 kPa. This solar thermal system operates in closed cycle conditions by including a check valve in its inlet–outlet junction; in this way, the fluid travels through the MHD generator. The MHD cell was composed of a block of polytetrafluoroethylene, two cylindrical stainless-steel electrodes, and four neodymium magnets. For simulation purposes, comsol multiphysics was used to reproduce the current density produced by the MHD solar generator. Pressure and temperature quantities obtained experimentally in the MHD cell were employed as boundary conditions. The experimental maximal current density obtained corresponds to 4.30 mA/m2, and the comparison between theoretical and experimental results shows that the model fits fairly well.

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Space Thermoacoustic Radioisotopic Power System, SpaceTRIPS: The Magnetohydrodynamic Generator

Sustainability ◽

10.3390/su132313498 ◽

2021 ◽

Vol 13 (23) ◽

pp. 13498

Author(s):

Arturs Brekis ◽

Antoine Alemany ◽

Olivier Alemany ◽

Augusto Montisci

Keyword(s):

Fluid Dynamic ◽

Mechanical Energy ◽

Electrical Energy ◽

Electricity Production ◽

One Dimensional ◽

Mhd Generator ◽

Deep Space Exploration ◽

Stage System ◽

Characteristic Values ◽

Eu Project

Electricity production is a major problem for deep space exploration. The possibility of using radioisotope elements with a very long life as an energy source was investigated in the framework of an EU project “SpaceTRIPS”. For this, a two-stage system was tested, the first in which thermal energy is converted into mechanical energy by means of a thermoacoustic process, and the second where mechanical energy is converted into electrical energy by means of a magnetohydrodynamic generator (MHD). The aim of the present study is to develop an analytical model of the MHD generator. A one-dimensional model is developed and presented that allows us to evaluate the behavior of the device as regards both electromagnetic and fluid-dynamic aspects, and consequently to determine the characteristic values of efficiency and power.

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Reduction of structural vibrations with the piezoelectric stacks ring

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209384 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 729-736

Author(s):

Jincheng He ◽

Xing Tan ◽

Wang Tao ◽

Xinhai Wu ◽

Huan He ◽

...

Keyword(s):

Vibration Control ◽

Mechanical Energy ◽

Electrical Energy ◽

Structural Vibrations ◽

Rotor Systems ◽

Fea Model ◽

Piezoelectric Stacks ◽

Shunt Damping ◽

Reduction Effect ◽

Euler Bernoulli Beam

It is known that piezoelectric material shunted with external circuits can convert mechanical energy to electrical energy, which is so called piezoelectric shunt damping technology. In this paper, a piezoelectric stacks ring (PSR) is designed for vibration control of beams and rotor systems. A relative simple electromechanical model of an Euler Bernoulli beam supported by two piezoelectric stacks shunted with resonant RL circuits is established. The equation of motion of such simplified system has been derived using Hamilton’s principle. A more realistic FEA model is developed. The numerical analysis is carried out using COMSOL® and the simulation results show a significant reduction of vibration amplitude at the specific natural frequencies. Using finite element method, the influence of circuit parameters on lateral vibration control is discussed. A preliminary experiment of a prototype PSR verifies the PSR’s vibration reduction effect.

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Utilization of electrical charges in the pores of tofu waste for hydrogen production in water

WEENTECH Proceedings in Energy ◽

10.32438/wpe.1720 ◽

2020 ◽

pp. 124-135

Author(s):

I. N. G. Wardana ◽

N. Willy Satrio

Keyword(s):

Magnetic Field ◽

Hydrogen Production ◽

Sodium Bicarbonate ◽

Positive Charge ◽

Electrical Energy ◽

Hydrogen Sensor ◽

Water Molecules ◽

Partial Charge ◽

Delocalized Electron ◽

Water Hydrogen

Tofu is main food in Indonesia and its waste generally pollutes the waters. This study aims to change the waste into energy by utilizing the electric charge in the pores of tofu waste to produce hydrogen in water. The tofu pore is negatively charged and the surface surrounding the pore has a positive charge. The positive and negative electric charges stretch water molecules that have a partial charge. With the addition of a 12V electrical energy during electrolysis, water breaks down into hydrogen. The test was conducted on pre-treated tofu waste suspension using oxalic acid. The hydrogen concentration was measured by a MQ-8 hydrogen sensor. The result shows that the addition of turmeric together with sodium bicarbonate to tofu waste in water, hydrogen production increased more than four times. This is due to the fact that magnetic field generated by delocalized electron in aromatic ring in turmeric energizes all electrons in the pores of tofu waste, in the sodium bicarbonate, and in water that boosts hydrogen production. At the same time the stronger partial charge in natrium bicarbonate shields the hydrogen proton from strong attraction of tofu pores. These two combined effect are very powerful for larger hydrogen production in water by tofu waste.

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On Energy Status indicators and the role of renewableEnergy under Economic Crisis

Voprosy Ekonomiki ◽

10.32609/0042-8736-2014-8-92-105 ◽

2014 ◽

pp. 92-105

Author(s):

P. Bezrukikh ◽

P. Bezrukikh (Jr.)

Keyword(s):

Renewable Energy ◽

World Economy ◽

Electrical Energy ◽

Primary Energy ◽

Primary Energy Consumption ◽

Energy Status ◽

Economy Growth ◽

The World ◽

Production Regime

The article analyzes the dynamics of consumption of primary energy and production of electrical energy in the world for 1973-2012 and the volume of renewable energy. It is shown that in the crisis year of 20 0 9 there was a significant reduction in primary energy consumption and production of electrical energy. At the same time, renewable energy has developed rapidly, well above the rate of the world economy growth. The development of renewable energy is one of the most effective ways out of the crisis, taking into account its production regime, energy, environmental, social and economic efficiency. The forecast for the development of renewable energy for the period up to 2020, compiled by the IEA, is analyzed. It is shown that its assessment rates are conservative; the authors justify higher rates of development of renewable energy.

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EXPERIMENTAL STUDIES OF CAR PROPERTIES ON A PHYSICAL MODEL

Avtoshliakhovyk Ukrayiny ◽

10.33868/0365-8392-2019-4-260-10-16 ◽

2019 ◽

pp. 10-16

Author(s):

Oleksii Timkov ◽

Dmytro Yashchenko ◽

Volodymyr Bosenko

Keyword(s):

Mathematical Model ◽

Remote Control ◽

Physical Model ◽

Model Experiment ◽

Experimental Studies ◽

Electrical Energy ◽

Short Term ◽

Motor Current ◽

Memory Card ◽

The Mathematical Model

The article deals with the development of a physical model of a car equipped with measuring, recording and remote control equipment for experimental study of car properties. A detailed description of the design of the physical model and of the electronic modules used is given, links to application libraries and the code of the first part of the program for remote control of the model are given. Atmega microcontroller on the Arduino Uno platform was used to manage the model and register the parameters. When moving the car on the memory card saved such parameters as speed, voltage on the motor, current on the motor, the angle of the steered wheel, acceleration along three coordinate axes are recorded. Use of more powerful microcontrollers will allow to expand the list of the registered parameters of movement of the car. It is possible to measure the forces acting on the elements of the car and other parameters. In the future, it is planned to develop a mathematical model of motion of the car and check its adequacy in conducting experimental studies on maneuverability on the physical model. In addition, it is possible to conduct studies of stability and consumption of electrical energy. The physical model allows to quickly change geometric dimensions and mass parameters. In the study of highway trains, this approach will allow to investigate the various layout schemes of highway trains in the short term. It is possible to make two-axle road trains and saddle towed trains, three-way hitched trains of different layout. The results obtained will allow us to improve not only the mathematical model, but also the experimental physical model, and move on to further study the properties of hybrid road trains with an active trailer link. This approach allows to reduce material and time costs when researching the properties of cars and road trains. Keywords: car, physical model, experiment, road trains, sensor, remote control, maneuverability, stability.

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