• Title/Summary/Keyword: MHD generation

Search Result 25, Processing Time 0.024 seconds

A Study on the Disk Type MHD Generator Using a Shock Tube (충격파관을 이용한 DISK형 MHD발전기에 관한 연구)

  • 배철오;신명철;김윤식;길경석
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.3 no.2
    • /
    • pp.447-453
    • /
    • 1999
  • In MHD power generation system, enthalpy of the working gas is convened to electric power directly through expansion in generator channel. It means that electric power can be generated without a moving mechanical linkage such as turbine blades. The principle of MHD generation is based on Faraday'law of induction that eletromotive force(u$\times$B) is generated when the working gas of velocity u flows a channel in which magnetic field of strength(B) exists. In this paper, helium gas seeded with cesium is used as working gas. There are two types of generator in MHD generation; linear type faraday and disk type hall generator. Rogowski coils having the bandwidth of the 100(Hz) ~ 20(kHz) were used for measuring current flowing MHD disk channel. Optimum load resistor value of the MHD generator studied was 2.5[$\Omega$]. Disk type hall generator's generation performance is the main target of this paper, which superiors to linear type Faraday generator in many points. Isentropic efficiency and enthalpy extraction rate of disk type shock tube driven hall generator is discussed here.

  • PDF

Studies on a Effective Scheme to Obtain High Temperature Working Plasma for MHD Power Generation (MHD발전용 작동 플라즈마를 고온가열하기 위한 효율적 방안에 관한 연구)

  • 김윤식;노창주;김영길;공영경;최춘성
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.17 no.1
    • /
    • pp.153-161
    • /
    • 1993
  • Heat transfer processes in the combustion chamber of a pebble bed regenerative heat exchanger for MHD power generation has been analyzed numerically for heating, evacuation argon heating periods individually. The calculated result well explain the measured temperature change at the top of the pebble bed. The analytical result point out that the length of evacution period and the geometry optimization both for the combustion chamber and the heat storage bed are very important factors for the improvement of thermal performance in MHD power generation.

Experiment on Small A.C. MHD Power Generator (소용량 교류 MHD발전기에 대한 실험적 연구)

  • Choon Saing Jhoun
    • 전기의세계
    • /
    • v.25 no.5
    • /
    • pp.79-87
    • /
    • 1976
  • This paper is to investigate the A.C generation of MHD engine, converting directly the kinetic energy of conductive gas in high temperature to electric power by the effect of magnetic field. It is known that there are at least two kinds of method in A.C MHD power generation; one, by sending stationary plasma flow in an alternating or rotating magnetic field and the other, by transmission of pulse type plasma flow in uniform and constant magnetic field, former method is adopted here. In order to raise the total efficiency of close cycle in combination with nuclear power and MHD genertaion, an argon plasma jet is utilized as heat source, which is not mixed with the seed material, and the design data are obtained for A.C MHD generation in small capacity, but induced voltage and power output have the maximum values, 15 voltages and 7.5W respectively due to plasma flow with low conductivity and weak magnetic field.

  • PDF

A evaluation of internal radial direction's distribution of MHD generator using shock tube (충격파관을 이용한 MHD발전기 내부 반경방향 분포의 평가)

  • 배철오;안병원;김윤식;이성근;박영산
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.4 no.2
    • /
    • pp.493-503
    • /
    • 2000
  • There are two types of generators in the MHD generation : linear type Faraday and disk type hall generator. In this paper, it is experimented disk type hall generator. Disk type generator is driven by shock tube that compresses working gas isentropically in a very short time. As a working gas, helium gas seeded with cesium is used. it is difficult to confirm the whole condition thorough oかy experiment because the things happened in MHD generator is very complex. Furthermore we can't how exactly what happen at the inside of generator's channel because the time of generation is very short and working gas flows out very high speed. Expecially it is almost impossible to measure the things occurred in the boundary layer using MHD generation experimental equipment driven shock uk. With above reasons, to know certainly how the several values happened inside disk MHD generator charge, some graphs were drawn linearly through calculation using measured experimental data. For the more, other calculated results which can't be obtained by only experiment are considered in this paper. And these calculated results are compared to experiment data how exactly done the calculation.

  • PDF

Present Research Status of MHD Electrical Power Generation

  • Shioda, Susumu
    • Proceedings of the KIEE Conference
    • /
    • 1989.07a
    • /
    • pp.3-8
    • /
    • 1989
  • Recent research activities for open and closed cycle MHD electrical power generations are reviewed. World first full scale 500MWe natural gas fired open cycle MHD is now under construction in USSR. Coal-fired open cycle MHD researches are in the stage of proof of concept and retrofitting of old coal power stations with MHD is planned in US and other countries. Basic research for closed MHD is most actively pursued in Japan, which potentially can provide a very high efficiency and a simple and reliable system.

  • PDF

MHD (Magnetohydrodynamic) Micropump Using Lorentz Force (로렌츠 힘을 이용한 MHD(Magnetohydrodynamic) 마이크로펌프)

  • 장재성;이승섭
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.15 no.11
    • /
    • pp.93-99
    • /
    • 1998
  • We present a novel micropump of which pumping mechanism is based upon MHD (Magnetohydrodynamic) principle. The MHD micropump uses Lorentz force as pumping source. In the MHD micropump, Lorentz force is applied into initially stagnant conducting fluid to drive it in magnetic and electric field to flow in both directions. The performance of the MHD micropump is obtained by measuring the pressure head difference and flow rate as applied voltage changes from 10 to 60 V DC at 0.19 and 0.44 Tesla. The pressure head difference is 18 mm at 38 mA and the flow rate is 63 ${\mu}{\ell}$ /min at 1.8 mA when the inside diameter of inlet/outlet tube is 2 mm and the magnetic flux density is 0.44 Tesla.

  • PDF

A Study on Enthalpy Extraction Rate and Isentropic Efficiency of the Disk Type Generator using a Shock Tube (충격파관을 이용한 DISK형 MHD발전기의 엔탈피추출율과 단열효율에 관한 연구)

  • Bae, C.O.;Kim, Y.S.;Park, Y.S.;Shin, S.M.
    • Proceedings of the KIEE Conference
    • /
    • 1998.07f
    • /
    • pp.1981-1983
    • /
    • 1998
  • The principle of the MHD generation is based on Faraday's law of induction that a eletromotive force(u ${\times}$ B) is generated when the working gas of velocity u flows a channel in which magnetic field of strength(B) exists. In MHD power generation system, enthalpy of the working gas is converted to electric power directly through expansion in generator channel. It means that electric power can be generated without moving mechanical linkage such as turbine blades. There are two types in the MHD generator; linear type Faraday and disk type hall generator. Disk type hall generator is the main target of this paper. Isentropic efficiency and enthalpy extraction rate of disk type shock tube driven hall generator is discussed here.

  • PDF

Magnetohydrodynamic (MHD) Micromixer Using Multi-Vortical Flow (다중 와류 유동을 이용한 자기유체역학 (MHD) 마이크로 믹서)

  • Yang, Won-Seok;Kim, Dong-Sung
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.34 no.1
    • /
    • pp.53-59
    • /
    • 2010
  • In this paper, we propose a novel chaotic micromixer of which mixing mechanism is based upon magnetohydrodynamic (MHD) multi-vortical flow generation in a simple straight microchannel. In the microchannel of the micromixer has electrodes patterned on two side walls and bottom wall. Lorentz forces are variously induced by changing applied voltages at the patterned electrodes in order to pump and mix conductive fluids in the microchannel. Three-dimensional computational fluid dynamics simulations were conduced to characterize mixing behaviors inside the MHD micromixer. The mixing efficiencies were also evaluated for the various flow conditions.

RADIATION EFFECTS ON MHD BOUNDARY LAYER FLOW OF LIQUID METAL OVER A POROUS STRETCHING SURFACE IN POROUS MEDIUM WITH HEAT GENERATION

  • Venkateswarlu, M.;Reddy, G. Venkata Ramana;Lakshmi, D. Venkata
    • Journal of the Korean Society for Industrial and Applied Mathematics
    • /
    • v.19 no.1
    • /
    • pp.83-102
    • /
    • 2015
  • The present paper analyses the radiation effects of mass transfer on steady nonlinear MHD boundary layer flow of a viscous incompressible fluid over a nonlinear porous stretching surface in a porous medium in presence of heat generation. The liquid metal is assumed to be gray, emitting, and absorbing but non-scattering medium. Governing nonlinear partial differential equations are transformed to nonlinear ordinary differential equations by utilizing suitable similarity transformation. The resulting nonlinear ordinary differential equations are solved numerically using Runge-Kutta fourth order method along with shooting technique. Comparison with previously published work is obtained and good agreement is found. The effects of various governing parameters on the liquid metal fluid dimensionless velocity, dimensionless temperature, dimensionless concentration, skin-friction coefficient, Nusselt number and Sherwood number are discussed with the aid of graphs.

Two-dimensional Numerical Simulation of a Pulsed Heat Source High Temperature Inert Gas Plasma MHD Electrical Power Generator

  • Matsumoto, Masaharu;Murakami, Tomoyuki;Okuno, Yoshihiro
    • Proceedings of the Korean Society of Propulsion Engineers Conference
    • /
    • 2008.03a
    • /
    • pp.589-596
    • /
    • 2008
  • Performance of a pulsed heat source high temperature inert gas plasma MHD electrical power generator, which can be one of the candidates of space-based laser-to-electrical power converter, is examined by a time dependent two dimensional numerical simulation. In the present MHD generator, the inert gas is assumed to be ideally heated to about $10^4K$ pulsed-likely within short time(${\sim}1{\mu}s$) in a stagnant energy input volume, and the energy of high temperature inert gas is converted to the electricity with the medium of pure inert gas plasma without seeding. The numerical simulation results show that an enthalpy extraction ratio(=electrical output energy/pulsed heat energy) of several tens of % can be achieved, which is the same level as the conventional seeded non-equilibrium plasma MHD generator. Although there still exist many phenomena to be clarified and many problems to be overcome in order to realize the system, the pulsed heat source high temperature inert gas MHD generator is surely worth examining in more detail.

  • PDF