TY - JOUR
T1 - Fully coupled finite element analysis for cooling effects of dielectric liquid due to ionic dissociation stressed by electric field
AU - Lee, Ho Young
AU - Kim, Young Sun
AU - Lee, Woo Seok
AU - Kim, Hong Kyu
AU - Lee, Se Hee
PY - 2013
Y1 - 2013
N2 - A fully coupled Finite Element Analysis (FEA) technique was developed and tested to validate the cooling effects of a dielectric liquid stressed by an electric field, resulting in the ionic dissociation phenomenon. Recently, electrohydrodynamics (EHD) techniques have been applied widely to enhance the cooling performance of electromagnetic systems by introducing gaseous or liquid media. The main advantage of EHD cooling is non-contact and low-noise resulting from smart control using an electric field. In addition, in some cases, the flow can be achieved using only a main electric field source not an extra one. The driving sources in EHD flow are ionization in the breakdown region and ionic dissociation in the sub-breakdown region. This study focused on dielectric liquid flow driven by the ionic dissociation phenomena, resulting in a cooling effect of the heat source. To build on this EHD phenomenon, fully coupled FEA, which consisted of the Poisson's equation for an electric field, Nernst-Planck equations for ions, and the Navier-Stokes equation for incompressible fluidic flow, was performed. To confirm the cooling effects, the developed velocities of fluidic flow were tested with the different applied voltages. In the sub-breakdown region, the effective velocity was approximately 2 m/s in the tip-sphere electrodes and a temperature drop of approximately 40°C was obtained in a numerical analysis model with a fluidic velocity of 1.96 m/s from the inlet.
AB - A fully coupled Finite Element Analysis (FEA) technique was developed and tested to validate the cooling effects of a dielectric liquid stressed by an electric field, resulting in the ionic dissociation phenomenon. Recently, electrohydrodynamics (EHD) techniques have been applied widely to enhance the cooling performance of electromagnetic systems by introducing gaseous or liquid media. The main advantage of EHD cooling is non-contact and low-noise resulting from smart control using an electric field. In addition, in some cases, the flow can be achieved using only a main electric field source not an extra one. The driving sources in EHD flow are ionization in the breakdown region and ionic dissociation in the sub-breakdown region. This study focused on dielectric liquid flow driven by the ionic dissociation phenomena, resulting in a cooling effect of the heat source. To build on this EHD phenomenon, fully coupled FEA, which consisted of the Poisson's equation for an electric field, Nernst-Planck equations for ions, and the Navier-Stokes equation for incompressible fluidic flow, was performed. To confirm the cooling effects, the developed velocities of fluidic flow were tested with the different applied voltages. In the sub-breakdown region, the effective velocity was approximately 2 m/s in the tip-sphere electrodes and a temperature drop of approximately 40°C was obtained in a numerical analysis model with a fluidic velocity of 1.96 m/s from the inlet.
KW - Conduction pumping
KW - dielectric liquid
KW - electric discharge
KW - electrohydrodynamics (EHD)
KW - incompressible media
KW - ionic dissociation
KW - Nernst-Planck equation
KW - sub-breakdown region
UR - http://www.scopus.com/inward/record.url?scp=84877853310&partnerID=8YFLogxK
U2 - 10.1109/TMAG.2013.2246551
DO - 10.1109/TMAG.2013.2246551
M3 - Article
AN - SCOPUS:84877853310
SN - 0018-9464
VL - 49
SP - 1909
EP - 1912
JO - IEEE Transactions on Magnetics
JF - IEEE Transactions on Magnetics
IS - 5
M1 - 6514699
ER -