ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels, 2012
In this study, a cross-sectional capacitance is measured in a microchannel with 12 multi-layered ... more In this study, a cross-sectional capacitance is measured in a microchannel with 12 multi-layered electrodes. The cross-sectional capacitance of polystyrene particles and deionized water is measured at upstream and downstream microchannel. Based on the measured cross-sectional capacitance, the particle volume fraction is calculated at three area measurements with different electrode pair. The three area measurements are at the adjacent pair, horizontal pair and vertical pair. The particle volume fraction at the adjacent pair area is almost same and higher at upstream and downstream cross-section. While at the vertical and horizontal pair areas, the particle volume fraction increased from upstream to downstream cross-section around 1.0–9.3% at electrode pair near the walls whilst decreased 0.4–0.96% at electrode pair near the center streamlines. It shows the particles are more attracted to migrate to the equilibrium position at near to the walls. The particles migration induced by ine...
ASME 2011 9th International Conference on Nanochannels, Microchannels, and Minichannels, Volume 1, 2011
ABSTRACT The present study describes the electrical tomography sensing and dielectrophoresis (DEP... more ABSTRACT The present study describes the electrical tomography sensing and dielectrophoresis (DEP) force for visualize the 3D particle mixing in the microchannel system. In the presence of non-uniform electric fields generated by point microelectrodes, the dynamic distribution behaviors of a polystyrene particle and deionized water had been investigated in this system. Microchannel was fabricated with five cross sections where 12 electrodes were installed for each measurement plane. In this experiment, the relationship between electric field frequency and DEP force of particles are calculated at different electric frequencies and diameter of particles. The applied electric field intensities are E = ±1 V/mm, ±3 V/mm and ±5 V/mm while the electric field frequencies are f = 1 kHz, 10 kHz, 100 kHz and 1 MHz and the diameter of particles are 1.3μm, 1.5μm and 2.0μm are investigated in this experiment. Simultaneously, imaged by manipulating tomography sensing at cross section A, C and D and the coupled DEP forces at cross section B and D, the particles flowing had been visualized and concentrate uniformly at near the outlets. The electrical capacitances and DEP forces between the electrode pairs of the microchannel were measured and the ECT tomograms representing the particle distribution were constructed from the measured capacitance data for each cross section in microchannel.
2011 International Symposium on Micro-NanoMechatronics and Human Science, 2011
In a present study, capacitance sensing is used as a visualization method for determination of di... more In a present study, capacitance sensing is used as a visualization method for determination of dielectric permittivity distribution in microchannel system from external capacitance measurement. The microchannel had fabricated using micro-electro-mechanical-systems (MEMS) advanced technology which has two inlets and outlets and five cross-sections that each cross-section was embedding with 12 electrodes pair that connected to the microchannel system. The capacitance
ASME 2013 11th International Conference on Nanochannels, Microchannels, and Minichannels, 2013
ABSTRACT Nowadays, fluid flow in a microchannel has emerged as an important area of research. Thi... more ABSTRACT Nowadays, fluid flow in a microchannel has emerged as an important area of research. This has been motivated by their various applications such as medical and biomedical use, computer chips, and chemical separations. Usually, electrical impedance tomography (EIT) is visualized, into a cross-sectional image representing the distribution of density. EIT is recently developed imaging technique, with which images of the conductivity or permittivity of the subject can be rapidly collected with channels of external electrodes. Therefore, we considered application of EIT to the microchannels. In this paper, we develop the EIT for microchannel nano particles concentration in microchannel with 60 multi-layer electrodes and measured using cross-sectional impedance measurement technique. Based on the reconstructed image using the EIT system and analytical calculation using Maxwell equation, we discuss the initial concentration condition effect and the stream transitional migration to estimate particle migration behaviors in the fluid flow. The measured results shows up to 24% particles moved from upstream to downstream cross-section, where the particles move away from center streamlines to near wall vicinity area and the number of the particles migration towards wall vicinity area is clearly increased near the outlet area. The stream transitional particle migration due to inertia lift forces is investigated with the effect of the initial particle concentration.
Droplet distribution is an importance factor to observe scrubber’s performance as uniform droplet... more Droplet distribution is an importance factor to observe scrubber’s performance as uniform droplets distribution improved the particle’s collection efficiency at minimal liquid usage. Yet, the optimization problem typically involves complicated model functions to predict particle’s collection efficiency and pressure drop. Since the interaction between liquid droplets and gas phase is complex and difficult to solve by an experimental approach. Thus in this study, the prediction of liquid droplet’s behavior in the venturi scrubber was observed by using computational fluid dynamic. The liquid was injected through two orifices on the throat wall. The droplet size at different position was observed at various range of a gas velocity from 70 to 100 m/s and the ratio of liquid to gas of 0.07 to 2.0 L/m to determine the optimum absorption rate. The droplet’s breakup in the venturi scrubber was observed using ANSYS simulation where two-fluid model Eulerian-Eulerian approach was applied. It sh...
ASME 2012 10th International Conference on Nanochannels, Microchannels, and Minichannels, 2012
In this study, a cross-sectional capacitance is measured in a microchannel with 12 multi-layered ... more In this study, a cross-sectional capacitance is measured in a microchannel with 12 multi-layered electrodes. The cross-sectional capacitance of polystyrene particles and deionized water is measured at upstream and downstream microchannel. Based on the measured cross-sectional capacitance, the particle volume fraction is calculated at three area measurements with different electrode pair. The three area measurements are at the adjacent pair, horizontal pair and vertical pair. The particle volume fraction at the adjacent pair area is almost same and higher at upstream and downstream cross-section. While at the vertical and horizontal pair areas, the particle volume fraction increased from upstream to downstream cross-section around 1.0–9.3% at electrode pair near the walls whilst decreased 0.4–0.96% at electrode pair near the center streamlines. It shows the particles are more attracted to migrate to the equilibrium position at near to the walls. The particles migration induced by ine...
ASME 2011 9th International Conference on Nanochannels, Microchannels, and Minichannels, Volume 1, 2011
ABSTRACT The present study describes the electrical tomography sensing and dielectrophoresis (DEP... more ABSTRACT The present study describes the electrical tomography sensing and dielectrophoresis (DEP) force for visualize the 3D particle mixing in the microchannel system. In the presence of non-uniform electric fields generated by point microelectrodes, the dynamic distribution behaviors of a polystyrene particle and deionized water had been investigated in this system. Microchannel was fabricated with five cross sections where 12 electrodes were installed for each measurement plane. In this experiment, the relationship between electric field frequency and DEP force of particles are calculated at different electric frequencies and diameter of particles. The applied electric field intensities are E = ±1 V/mm, ±3 V/mm and ±5 V/mm while the electric field frequencies are f = 1 kHz, 10 kHz, 100 kHz and 1 MHz and the diameter of particles are 1.3μm, 1.5μm and 2.0μm are investigated in this experiment. Simultaneously, imaged by manipulating tomography sensing at cross section A, C and D and the coupled DEP forces at cross section B and D, the particles flowing had been visualized and concentrate uniformly at near the outlets. The electrical capacitances and DEP forces between the electrode pairs of the microchannel were measured and the ECT tomograms representing the particle distribution were constructed from the measured capacitance data for each cross section in microchannel.
2011 International Symposium on Micro-NanoMechatronics and Human Science, 2011
In a present study, capacitance sensing is used as a visualization method for determination of di... more In a present study, capacitance sensing is used as a visualization method for determination of dielectric permittivity distribution in microchannel system from external capacitance measurement. The microchannel had fabricated using micro-electro-mechanical-systems (MEMS) advanced technology which has two inlets and outlets and five cross-sections that each cross-section was embedding with 12 electrodes pair that connected to the microchannel system. The capacitance
ASME 2013 11th International Conference on Nanochannels, Microchannels, and Minichannels, 2013
ABSTRACT Nowadays, fluid flow in a microchannel has emerged as an important area of research. Thi... more ABSTRACT Nowadays, fluid flow in a microchannel has emerged as an important area of research. This has been motivated by their various applications such as medical and biomedical use, computer chips, and chemical separations. Usually, electrical impedance tomography (EIT) is visualized, into a cross-sectional image representing the distribution of density. EIT is recently developed imaging technique, with which images of the conductivity or permittivity of the subject can be rapidly collected with channels of external electrodes. Therefore, we considered application of EIT to the microchannels. In this paper, we develop the EIT for microchannel nano particles concentration in microchannel with 60 multi-layer electrodes and measured using cross-sectional impedance measurement technique. Based on the reconstructed image using the EIT system and analytical calculation using Maxwell equation, we discuss the initial concentration condition effect and the stream transitional migration to estimate particle migration behaviors in the fluid flow. The measured results shows up to 24% particles moved from upstream to downstream cross-section, where the particles move away from center streamlines to near wall vicinity area and the number of the particles migration towards wall vicinity area is clearly increased near the outlet area. The stream transitional particle migration due to inertia lift forces is investigated with the effect of the initial particle concentration.
Droplet distribution is an importance factor to observe scrubber’s performance as uniform droplet... more Droplet distribution is an importance factor to observe scrubber’s performance as uniform droplets distribution improved the particle’s collection efficiency at minimal liquid usage. Yet, the optimization problem typically involves complicated model functions to predict particle’s collection efficiency and pressure drop. Since the interaction between liquid droplets and gas phase is complex and difficult to solve by an experimental approach. Thus in this study, the prediction of liquid droplet’s behavior in the venturi scrubber was observed by using computational fluid dynamic. The liquid was injected through two orifices on the throat wall. The droplet size at different position was observed at various range of a gas velocity from 70 to 100 m/s and the ratio of liquid to gas of 0.07 to 2.0 L/m to determine the optimum absorption rate. The droplet’s breakup in the venturi scrubber was observed using ANSYS simulation where two-fluid model Eulerian-Eulerian approach was applied. It sh...
Uploads
Papers by Nur Tantiyani Ali Othman