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Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The hydrogen production by conversion of liquid compounds containing hydrogen was investigated experimentally. The waveguide-supplied metal cylinder-based microwave plasma source (MPS) operated at frequency of 915 MHz at atmospheric pressure was used. The decomposition of ethanol, isopropanol and kerosene was performed employing plasma dry reforming process. The liquid was introduced into the plasma in the form of vapour. The amount of vapour ranged from 0.4 to 2.4 kg/h. Carbon dioxide with the flow rate ranged from 1200 to 2700 NL/h was used as a working gas. The absorbed microwave power was up to 6 kW. The effect of absorbed microwave power, liquid composition, liquid flow rate and working gas fl ow rate was analysed. All these parameters have a clear influence on the hydrogen production efficiency, which was described with such parameters as the hydrogen production rate [NL(H2)/h] and the energy yield of hydrogen production [NL(H2)/kWh]. The best achieved experimental results showed that the hydrogen production rate was up to 1116 NL(H2)/h and the energy yield was 223 NL(H2) per kWh of absorbed microwave energy. The results were obtained in the case of isopropanol dry reforming. The presented catalyst-free microwave plasma method can be adapted for hydrogen production not only from ethanol, isopropanol and kerosene, but also from different other liquid compounds containing hydrogen, like gasoline, heavy oils and biofuels.

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the results of an experimental study on hydrogen production at a tungsten discharge electrode with negative polarity in the DC electrolysis of a typical 10 wt% Na2CO3 aqueous solution in three operational regimes (the Faradaic, transition, and plasma-driven solution electrolysis (PDSE)) are presented for the first time. To focus the study on hydrogen production, a flowing inert gas (argon) was used to transport the gas mixture produced at the discharge electrode and prevent any other potential chemical reactions. The results showed that the highest hydrogen production rate of 0.147 g(H2)/h was achieved in the cathodic PDSE regime at the applied DC voltage of 198 V. However, the energy yield of hydrogen production of 0.405 g(H2)/kWh obtained at the applied voltage range of 141–170 V in the PDSE regime was lower than that obtained in the Faradaic regime (0.867 g(H2)/kWh) at 28 V. The energy balance of hydrogen production in the cathodic PDSE regime for the typical aqueous solution of Na2CO3 carried out for the first time showed that a significant share (˃98%) of the electrical energy consumed is spent on heating and evaporation of the electrolytic solution. This explains why the energy yield of hydrogen production is low in the PDSE regime. Because most of the energy is consumed for heat generation in the cathodic PDSE regime, organic liquid hydrogen carriers, such as alcohols, which have a lower boiling temperature, heat of evaporation, and standard Gibbs free energy, should be considered better aqueous electrolytic solutions in terms of the energy yield of hydrogen production in the PDSE regime. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

2D Particle Image Velocimetry (PIV) measurements were performed in a wirenonparallel plates type electrobydrodynamic (EHD) gas pump. The effect of electrode configuration and polarity of the active electrode on the flow pattern inside the pump was studied. One can deduce from the obtained flow patterns that the flow generated inside the EHD pump is three dimensional. The vortices formed inside the EHD gas pump have negative effect on pumping capabilities of the pump since the vortices may block and suppress the generated flow. The PIV results will be compared with a numerical modelling of the flow, based on k-E model. Index Terms--Particle image velocimetry, PIV, electrohydrodynamic pump, EHD, corona discharges, non-thermal plasmas.

2D Particle Image Velocimetry (PIV) measurements were performed in a wirenonparallel plates type electrohydrodynamic (EHD) gas pump. Using simultaneously two CCD cameras allowed obtaining high resolution vector maps which illustrate the flow patterns generated inside the EHD gas pump. Index Terms--Particle Image Velocimetry, electrohydrodynamic pump, Corona discharges, Non-thermal plasmas

Planar laser-induced fluorescence was employed during the process of N[O.sub.x] removal in a corona radical shower system. Using the wide-range imaging (image size: 240 mm in width and 160 mm in height), two-dimensional distributions of ground-state NO could be observed not only in the discharge zone but also both in the downstream and the upstream regions of the reactor. The obtained results showed that the density of NO molecules decreased not only in the plasma region formed by the corona streamers and the downstream region of the reactor but also in the upstream region of the reactor. The effect of the gas injection through the nozzles electrode on the NO profile in the reactor was negligible. The NO removal rate was almost the same for both cases with and without the injection gas once the streamer discharge was produced. In the present reactor at low main gas How rate, it was considered that electrohydrodynamic flow became to be dominant, and the flow toward the upstream affected the decrease of NO in the upstream region. This fact is important for optimizing the performance of the nonthermal plasma reactor. Index Terms--Corona radical shower system, electrohydrodynamic (EHD) flow, planar laser-induced fluorescence (PLIF), streamer, wide-range two-dimensional NO concentration distribution.

New arguments supporting the supposition that the ozone is transported along a corona discharge radical shower (CDRS) reactor by the electrohydrodynamic (EHD) flow are presented. The arguments are based on the analysis of the corona discharge, which is a precursor of the EHD flow in the CDRS reactor, and on the measurements of velocity field of the EHD flow in the CDRS reactor by the particle image velocimetry (PIV). The obtained velocity flow structures and the possible causes of the ozone transport in the CDRS, i.e., diffusion, additional gas flow, EHD flow, and convection by the main flow, were discussed basing on the conservation equations for the EHD flow. The discussion showed that the EHD flow plays a dominant role in the ozone transport. This is also supported by the results of a simple phenomenological model for one-dimensional description of EHD-induced ozone transport in the CDRS reactor. The results of the computer simulation based on this model explained the main features of the measured ozone distribution in the CDRS reactor, establishing the EHD flow as the main cause of the ozone transport from the discharge region upstream, i.e., against the main flow. Index Terms--Corona discharge radical shower (CDRS), electrohydrodynamic flow, particle image velocimetry.

Features of the streamer-corona discharge and the NO processing area in corona radical shower system was studied experimentally. The time evolution of the streamer-corona discharges induced by laser irradiations was measured to understand the discharge characteristics responsible for NO removal. Using the wide-range planar laser-induced fluorescence imaging (image size: 240 mm in width and 35 mm in height), two-dimensional distributions of ground-state NO were observed not only at the discharge zone but also both the downstream and the upstream regions of the reactor. The obtained results showed that the density of NO molecules decreased not only in the plasma region formed by the corona streamers and downstream region of the reactor but also in the upstream region of the reactor. In the present reactor at low main gas flow rate, it was considered that electrohydrodynamic (EHD) flow became to be dominant, and the flow toward the upstream affected the decrease of NO in the upstream region. As the EHD-induced secondary flow is correlated with the current flow from the stressed electrode to grounded electrode, the control of the streamers seems to be an important factor for optimizing the reactors used for NOx removal. Index Terms--Electrohydrodynamic (EHD) flow, NO removal, planar laser-induced fluorescence (PLIF), streamer.

Two-dimensional NO concentration distribution was studied by a planar laser-induced fluorescence (PLIF) technique in nonthermal plasma during NO treatment. A pipe with a nozzles-to-plate electrode system, having an electrode gap of 50 mm, was used. A stable dc streamer corona discharge was generated in an NO/air mixture at atmospheric pressure. Laser pulses in the form of a sheet were shot between the electrodes during the discharge. LIF signal emitted at 90[degrees] to the laser sheet was imaged onto a gated-ICCD camera and two-dimensional distributions of NO concentration in the reactor were measured as a function of time during NO treatment. NO concentration was also monitored at the reactor outlet. The images of NO concentration covering almost the whole length of the reactor show that the density of NO molecule decreased not only in the plasma region formed by corona streamers but also in the upstream region of the reactor. This information is important for modeling and optimizing the plasma processes and designing the nonthermal plasma reactors. Index Terms--Electrohydrodynamic (EHD) flow, planar laser-induced fluorescence (PLIF), streamer corona discharge, two-dimensional NO concentration distribution.

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Two-dimensional distribution of the ground-state NO molecules density was investigated using laser-induced fluorescence (LIF) technique in a dc positive streamer corona reactor (needle-to-plate electrode geometry) during NO removal from a flue gas simulator (NO/air). NO density in the corona discharge reactor was monitored under the steady-state dc corona discharge condition. It was found that NO molecules density decreased due to the corona discharge processing not only in the discharging region but also in the upstream vicinity of the discharge. Index Terms--DC positive streamer corona, ground-state NO molecule, laser-induced fluorescence, NO removal.