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Visualization of a streak line pattern in a mixing vessel is quite useful for understanding the mixing mechanism and designing an optimal mixing vessel. However, conventional experimental methods for visualizing streak lines require a lot of time to construct impellers and prepare solutions. Although various commercial fluid analysis software has been developed, there are still no examples of its use for calculating streak lines in mixing vessels. A simulation method was developed to quickly evaluate the streak line pattern in a laminar mixing vessel by numerical analysis with commercial code. A commercial CFD code can calculate streak line patterns in a laminar mixing vessel. It was found that a lattice method was more suitable than a particle method for the simulation of the streak line.

A mixing performance of an inner baffle was investigated in shear thinning fluid. The inner baffle was placed with a clearance between baffle and vessel wall. A traditional two-bladed paddle impeller was used. Four planar baffles were vertically placed in two ways: 1) standard baffle condition 2) inner baffle condition. The standard baffle condition was that the baffle was placed on the mixing vessel wall. A mixing pattern was visualized by decolorization method based on an oxidation-reduction reaction with sodium thiosulfate and iodine. Flow field for shear thinning fluid in mixing vessel was measured by particle image velocimetry and was shown as stream line. A pair of isolated mixing regions (IMR) like doughnut-ring formed above and below the impeller under standard baffle condition. However, IMR dissipated under inner baffle condition. As a result, a mixing time under the inner baffle condition was drastically decreased. This study suggested that inner baffle promoted mixing in shear thinning fluid.

The effects of the location of the baffle on mixing pattern in laminar mixing is shown in this study. Decolorization experiments were conducted based on an oxidation-reduction reaction to investigate the mixing pattern. As a result, isolated mixing regions (IMR) like doughnut-rings were eliminated by setting the baffle at the optimum location, where the baffle and the IMR crossed each other. The velocity profile was measured by using particle image velocimetry under the baffle condition. The IMR was dissipated due to making unstable circulation flow when the baffle was placed with clearance between the baffle and the wall. It was shown that using conventional mixing equipment can eliminate the IMR easily by placing the baffle with clearance.

The gas-liquid mass transfer volumetric coefficient (KLa) and power consumption under aeration are important parameters for designing gas-liquid agitated vessel. In this work, KLawas calculated by measuring the dissolved oxygen concentration and the mixing power consumption was calculated by measuringshaft torque in the aerated mixing vessel equipped with several types of large paddle impeller. It was found that the aerated mixing power consumption with the large paddle impellers did not decrease largely, because the large cavity was not formed behind the impeller blade. Then, KLa of large paddle impellers used was correlated with a modified equation of Sato et al. The intercept of Sato’s equation was correlated with the viscosity of CMC aqueous solution. KLaof large paddle impellers is estimated by using the modified Sato’s equation over a wide range of viscosity.

Power consumption is an important parameter for the design of mixing equipment. The aim of this study is to develop a new correlation of the power consumption of a double impeller. The effect of impeller spacing on the double-impeller flow pattern and power consumption was investigated in the laminar region. As a result, the effect of impeller spacing on the flow pattern was described based on the ratio of impeller spacing to the impeller blade height. Moreover, the power consumption of a double impeller could be correlated with the same ratio.

The power numbers of several kinds of impellers in rectangular eccentric vessels were correlated with Kamei et al.’s modified equation for a wide range of Reynolds numbers. The mixing patterns of these impellers were observed by using a decolorization method based on the reaction between sodium thiosulfate and iodine. A relationship was established between the power number diagram (NP–Re diagram) and the shape of the isolated zone. At low Reynolds numbers, isolated zones like donut rings were observed in the rectangular vessels and in a cylindrical vessel without baffles.

The flow pattern and the solid-liquid mass transfer coefficient in figure-eight shaking vessels were observed by experimental method. The flow patterns, mixing time, power consumption and mass transfer coefficient in the figure- eight shaking vessels changed irregularly with increase in the shaking frequency. Any frequency, even in the Fr = 0.095 or more became clear experimentally. The region of the optimum operating condition of the figure-eight shaking was larger than that of the reciprocal shaking. The solid-liquid mass transfer coefficient was correlated with the same cor- relation as that of the rotary shaking vessel of existing. The gas-liquid mass transfer coefficient of the figure-eight shak- ing vessel was also correlated with the same type of correlation as that of the rotary shaking vessel of existing.

In Japan, regulations on low-frequency magnetic fields came into force. Initial regulations in 2011 applied to power equipment in general, but the scope of regulatory control was expanded in 2012 to cover track-side railway power equipment. Although railway vehicles are not included in the scope of the regulation at the moment, it thought that it is necessary to assess magnetic fields in railway vehicles. As such a series of studies have been launched to develop a method to measure and predict low-frequency magnetic fields in railway vehicles.

Disposable shaking bioreactors are a promising alternative to other disposable bioreactors owing to their ease of operation, flexibility, defined hydrodynamics and characterization. Shaken bioreactors of sizes 20 L and 50 L are characterized in terms of heat transfer characteristics in this research work. Water and an 80% glycerol–water system were used as fluid. Results indicated large heat generation due to shake mixing which was observed by temperature difference between the fluid inside the vessel and the surrounding air outside the vessel. Maximum temperature difference of ca. 30 K was encountered for a 50 L vessel, at 300 rpm and 20 L filling volume. Outside heat transfer rate was governing the overall heat transfer process. Lateral air flow did increase heat transfer rates to large extent. An empirical correlation of overall heat transfer coefficient was obtained in terms of filling volume, rotational speed and lateral air flow rate. However, as the vessel thickness increased, the overall heat transfer process was limited by vessel wall resistance.

TiO 2 /Cu 2 O heterojunction solar cells were fabricated by two low-cost chemical techniques. TiO 2 thin films were fabricated by electrophoretic deposition using a TiO 2 sol solution. An approximately 0.5 μm-thick film was deposited with a deposition time of 1 s. Cu 2 O thin films were fabricated by electrodeposition using an aqueous CuSO 4 solution with pH adjusted to 12.5. The heterojunction solar cells were fabricated by first depositing TiO 2 on the indium-tin-oxide glass substrate, and then depositing Cu 2 O on TiO 2 . The cells were annealed in air atmosphere. A conversion efficiency of about 0.1% was achieved after annealing at 120 °C.

This article examines the application of a contactless power supply system to battery-run or hybrid trains. The potential advantages of this system include low noise emittance, maintenance-free features, and the elimination of electric shocks or leaks. The system's disadvantages include a reduction in energy supply efficiency as a result of energy transmission through space, as well as increased equipment costs. This report addresses efforts to overcome the system's challenges with the use of coil configurations.