A low power atmospheric pressure plasma jet driven by a 24 kHz AC power source and operated with a CH4/air gas mixture has been investigated by optical emission spectrometer. The plasma parameters including the electr...A low power atmospheric pressure plasma jet driven by a 24 kHz AC power source and operated with a CH4/air gas mixture has been investigated by optical emission spectrometer. The plasma parameters including the electron excitation temperature, vibrational temperature and rotational temperature of the plasma jet at different discharge powers are diagnosed based on the assumption that the kinetic energy of the species obeys the Boltzmann distribution. The electron density at different power is also investigated by HS Stark broadening. The results show that the plasma source works under non-equilibrium conditions. It is also found that the vibrational temperature and rotational temperat;ure increase with discharge power, whereas the electron excitation temperature seems to have a downward trend. The electron density increases from 0.8×10^21 m^-3 to 1.1×10^21 m^-3 when the discharge power increases from 53 W to 94 W.展开更多
To improve the durability of underwater rotating products,the corrosion characteristics in harsh marine environment were evaluated through various electrochemical experiments on the Al2O3-3TiO2 and CoNiCrAlY coating l...To improve the durability of underwater rotating products,the corrosion characteristics in harsh marine environment were evaluated through various electrochemical experiments on the Al2O3-3TiO2 and CoNiCrAlY coating layers by atmospheric pressure plasma spray coating process.By evaluating the corrosion resistance of these materials,their applicability to environmentally friendly power generation equipment such as blades of tidal current turbines was examined.According to the Tafel analysis for micro-areas including the coating layer,the coating/metal interlayer and the base metal,the Al2O3-3TiO2 coating layer and the CoNiCrAlY coating layer show markedly lower corrosion current density than the base metal.The corrosion current density of the CoNiCrAlY coating layer (9.75316×10-8A/cm2) is about 1.6 times more than that of the Al2O3-3TiO2 coating layer (6.13139×10-8A/cm2).展开更多
The rotating jet bed(RJB) has been developed by Zhejiang University of Technology,as a noveler type of gas-liquid mass-transfer unit than rotating zigzag bed(RZB).The rotor of RJB is composed of perforated concentric ...The rotating jet bed(RJB) has been developed by Zhejiang University of Technology,as a noveler type of gas-liquid mass-transfer unit than rotating zigzag bed(RZB).The rotor of RJB is composed of perforated concentric baffles fixed to a rotating disc.The top of the baffles is in the grooves of the stationary disc,preventing short cut of the gas.Experiments of total reflux distillation with RZB and two types of RJB were carried out with ethanol-water systems at atmospheric pressure.The two types of RJB are with rotor of mesh baffles and of shutter baffles,respectively.The results showed that the number of theoretical plates per meter of RJB,lower than that of RZB,increased with increasing rotational speed,and increased firstly and then decreased with increasing gas superficial F-factor.The maximum number of theoretical plates per meter is 40.7 for RJB with rotor of mesh baffles and 40.0 for RJB with rotor of shutter baffles.The specific pressure drop of RJB was far less than that of RZB.The gas phase film volumetric mass-transfer coefficients of RJB with rotor of mess baffles and shutter baffles were correlated with the Reynolds number,Grashof number and Schmidt number.The calculated value agreed well with the experimental value,and the average deviation was less than 15%.展开更多
文摘A low power atmospheric pressure plasma jet driven by a 24 kHz AC power source and operated with a CH4/air gas mixture has been investigated by optical emission spectrometer. The plasma parameters including the electron excitation temperature, vibrational temperature and rotational temperature of the plasma jet at different discharge powers are diagnosed based on the assumption that the kinetic energy of the species obeys the Boltzmann distribution. The electron density at different power is also investigated by HS Stark broadening. The results show that the plasma source works under non-equilibrium conditions. It is also found that the vibrational temperature and rotational temperat;ure increase with discharge power, whereas the electron excitation temperature seems to have a downward trend. The electron density increases from 0.8×10^21 m^-3 to 1.1×10^21 m^-3 when the discharge power increases from 53 W to 94 W.
基金Project supported by the Ministry of Education,Science Technology(MEST)Korea Industrial Technology Foundation(KOTEF)through the Human Resource Training Project for Regional Innovation
文摘To improve the durability of underwater rotating products,the corrosion characteristics in harsh marine environment were evaluated through various electrochemical experiments on the Al2O3-3TiO2 and CoNiCrAlY coating layers by atmospheric pressure plasma spray coating process.By evaluating the corrosion resistance of these materials,their applicability to environmentally friendly power generation equipment such as blades of tidal current turbines was examined.According to the Tafel analysis for micro-areas including the coating layer,the coating/metal interlayer and the base metal,the Al2O3-3TiO2 coating layer and the CoNiCrAlY coating layer show markedly lower corrosion current density than the base metal.The corrosion current density of the CoNiCrAlY coating layer (9.75316×10-8A/cm2) is about 1.6 times more than that of the Al2O3-3TiO2 coating layer (6.13139×10-8A/cm2).
文摘The rotating jet bed(RJB) has been developed by Zhejiang University of Technology,as a noveler type of gas-liquid mass-transfer unit than rotating zigzag bed(RZB).The rotor of RJB is composed of perforated concentric baffles fixed to a rotating disc.The top of the baffles is in the grooves of the stationary disc,preventing short cut of the gas.Experiments of total reflux distillation with RZB and two types of RJB were carried out with ethanol-water systems at atmospheric pressure.The two types of RJB are with rotor of mesh baffles and of shutter baffles,respectively.The results showed that the number of theoretical plates per meter of RJB,lower than that of RZB,increased with increasing rotational speed,and increased firstly and then decreased with increasing gas superficial F-factor.The maximum number of theoretical plates per meter is 40.7 for RJB with rotor of mesh baffles and 40.0 for RJB with rotor of shutter baffles.The specific pressure drop of RJB was far less than that of RZB.The gas phase film volumetric mass-transfer coefficients of RJB with rotor of mess baffles and shutter baffles were correlated with the Reynolds number,Grashof number and Schmidt number.The calculated value agreed well with the experimental value,and the average deviation was less than 15%.
