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This paper aims to computationally investigate flow patterns of gas-liquid two-phase with an abrupt expansion. To do so, the present computation is nicely verified against the previous experimental results for a good wettability surface. These rectangular channels have a thickness narrower than the Laplace constant of the present situation. Under a poor wettability condition, this narrow thickness affects the flow pattern; e.g., the air phase forms channeling behind the expansion in a low airflow rate whereas the air phase becomes fragments of bubbles due to the expansion under a good wettability condition.

Introduction Increasing the energy efficiency of cars, resulting in improved fuel economy, has received attention from time to time in various regions of the world. The main driving forces - today and historically - have been increasing energy prices and concerns about exhaust emissions. Reduced fuel use implies both lower fuel cost and lower emissions of carbon dioxide (CO2). Due to the increasing attention these driving forces receive worldwide, fuel economy improvements form the basis for car manufacturers’ competitiveness in the global market. Fuel economy regulation is no doubt one of the factors that influence, direct and strengthen the fuel economy of cars, and such regulation has hitherto been implemented at regional or national levels. A prominent example is Japan, which plays a dominant role in the car industry while also having a strong tradition of fuel economy regulation. The purpose of this chapter is to explain how the development of fuel economy regulation for cars in Japan was achieved. This is contrasted with corresponding regulation in the United States and the European Union (EU). Implications of the regulations for the Japanese car industry are proposed, and other potentially influential factors are discussed. The data used for analysis are collected through related documents, including official government reports and policy papers by non-governmental organizations (NGOs) and research institutes, as well as interviews conducted with government officials and the car industry. First, this chapter looks at how the decision process of Japanese fuel economy regulations, which can be characterized as ‘co-regulation’ between the government and the industry, has backed up the development. Second, we analyse how fuel economy regulation of Japan’s major car export markets - the United States and the EU - has encouraged sustainable technological innovation in the Japanese industry. Third, other influential factors than fuel economy regulation, such as the, Part of book: ISBN 978-1-136-31661-6, ISBN 978-0-415-68360-9QC 20220623

This paper aims to computationally investigate flow patterns of gas-liquid two-phase with an abrupt expansion. To do so, the present computation is nicely verified against the previous experimental results for a good wettability surface. These rectangular channels have a thickness narrower than the Laplace constant of the present situation. Under a poor wettability condition, this narrow thickness affects the flow pattern; e.g., the air phase forms channeling behind the expansion in a low airflow rate whereas the air phase becomes fragments of bubbles due to the expansion under a good wettability condition.

This paper virtually demonstrates an air cavity formed by a superhydrophobic low-density sphere entering into water with the use of a high-speed camera. Unlike the previous results for a high-density sphere, the low-density sphere pinches off the resulting air cavity at the shorter depth before the cavity has fully grown, and attracts minimal air on the rear surface due to rapid deceleration of the sphere in water. The analytical model previously proposed on the time evolution of the cavity shape is thus shown to be no longer valid for the low-density sphere.

This paper virtually demonstrates an air cavity formed by a superhydrophobic low-density sphere entering into water with the use of a high-speed camera. Unlike the previous results for a high-density sphere, the low-density sphere pinches off the resulting air cavity at the shorter depth before the cavity has fully grown, and attracts minimal air on the rear surface due to rapid deceleration of the sphere in water. The analytical model previously proposed on the time evolution of the cavity shape is thus shown to be no longer valid for the low-density sphere.

The emergence of technology-oriented agreements such as the 2005 Asia-Pacific Partnership on Clean Development and Climate (APP) may have significant implications for the future of global climate governance, as these agreements could be perceived as an alternative for the existing international climate regime. It is, therefore, important to examine what has moved countries to be involved in these agreements alongside the UN climate regime. This article seeks to identify possible factors contributing to Japan's participation in both the UN climate regime and the APP, looking at the position of domestic interest groups, the distribution of climate policy-making at the government level and varying international pressures. It concludes that Japan's participation in both the APP and the UN climate regime flows from a policy-making process that tries to accommodate conflicting viewpoints at the domestic and international levels. To what extent Japan's participation in both fora can be regarded as constructive will depend on the partnership's ability to support the implementation of a future climate regime. © The Author(s) 2009.

The emergence of technology-oriented agreements such as the 2005 Asia-Pacific Partnership on Clean Development and Climate (APP) may have significant implications for the future of global climate governance, as these agreements could be perceived as an alternative for the existing international climate regime. It is, therefore, important to examine what has moved countries to be involved in these agreements alongside the UN climate regime. This article seeks to identify possible factors contributing to Japan's participation in both the UN climate regime and the APP, looking at the position of domestic interest groups, the distribution of climate policy-making at the government level and varying international pressures. It concludes that Japan's participation in both the APP and the UN climate regime flows from a policy-making process that tries to accommodate conflicting viewpoints at the domestic and international levels. To what extent Japan's participation in both fora can be regarded as constructive will depend on the partnership's ability to support the implementation of a future climate regime. © The Author(s) 2009.

The main fluid-flow pattern that results in a converter with side gas injection was studied using physical modeling. Having roughly the same viscosity as liquid steel, water was used in the experiments. The velocity of the water was determined for different positions in the vessel symmetry plane by laser Doppler velocimetry. Experiments were performed using combinations of three different bath heights and four different gas-flow rates. The results showed penetration of the gas plume into the steel bath both at the tuyere and bath level to increase with an increased gas-flow rate. Also, the penetration depth of the gas both at the tuyere and bath surface level were more affected by an increased gas-flow rate than an increased bath height. Finally, the overall fluid-flow pattern in the system was found to change both with an increased bath height and an increased gas-flow rate., QC 20100525

Cold model experiments were carried out to understand a swinging motion of the bath in the AOD process. Water and air were used as the working fluids. A water bath contained in a cylindrical vessel was agitated by side gas injection using an L-shaped lance. Under a certain blowing condition the surface of the bath swung in the vertical direction like a liquid column oscillating in a U-shaped tube. The preferable occurrence condition of this swinging motion was correlated with the size of a plume eye on the bath surface and the vessel diameter. Empirical equations were proposed for the period and amplitude of the swinging motion., QC 20100525 QC 20111102

A numerical analysis and a water model study of the mold region of a billet continuous caster was performed with a novel injection concept using swirling flow in the pouring tube, to control the heat and mass transfer in the continuous casting mold. The following results were found: A weak impinging flow can be observed near the corner of the mold wall, which results in the promotion of uniform heat and mass transfer all around across the plane, particularly at the casting corner. An upward flow directed from the vicinity of the nozzle outlet to the meniscus can be observed near the corner of the upper part of the mold, which leads to the active heat and mass transfer into the meniscus. A uniform velocity and heat distribution can be obtained within a short distance of 200 mm downward from the outlet of the nozzle. Quite different mold flow patterns are observed between the divergent and straight immersion nozzles. Heat and mass transport in the mold using the divergent nozzle is much more reasonable than that using the straight nozzle., QC 20111028

A new efficient algorithm consisting of a stereo-pair matching and a particle-tracking is developed for three-dimensional particle tracking velocimetry. In the former procedure, three-dimensional coordinates of particles can be determined efficiently by identifying particles between pictures taken simultaneously from multiple directions. The latter one is a three-dimensional binary correlation method, which can identify particles between two sequential pictures by evaluating similarity between two local patterns of three-dimensionally distributed particles. Performances of the new method such as the measurement accuracy of coordinates of particles, the reliability of estimated particle-pairs, and the analyzing speed are examined. (Author)

Measurements of mean velocity, turbulence intensity and Reynolds shear stress were made using a two-dimensional LDV system for a vertical bubbling jet in a cylindrical water bath subject to centric gas injection. The Reynolds shear stress in bubbling jet was such higher than that in single-phase free jet and almost agreed with estimated values based on the boundary layer approximation and the Boussinesq approximation. (Author)

The effects of acid concentration, temperature, leaching duration and oxidising agents on hydrometallurgical recovery of the valuable metals were studied. X-ray diffraction analysis identified the positive electrode materials as Ni(OH)2 and Ni, and the negative electrode material as LaNi5. The nickel hydroxide was easily leached with dilute H2SO4, while the addition of oxidising agents allowed effective leaching of the nickel. A practical process for separating the materials before leaching was tested; it included cutting, heat treatment, magnetic separation and screening., The effects of acid concentration, temperature, leaching duration and oxidising agents on hydrometallurgical recovery of the valuable metals were studied. X-ray diffraction analysis identified the positive electrode materials as Ni(OH)2 and Ni, and the negative electrode material as LaNi5. The nickel hydroxide was easily leached with dilute H2SO4, while the addition of oxidising agents allowed effective leaching of the nickel. A practical process for separating the materials before leaching was tested; it included cutting, heat treatment, magnetic separation and screening.

The steady vibration of a flexible circular plate with finite rigidity resting on an elastic half space and subjected to harmonic vertical loads on the surface of the plate is studied in the present paper. The contact between the plate and the half space is assumed to be frictionless. Three types of load are considered: 1. the load uniformly distributed over the entire surface of the plate, 2. the load uniformly distributed over a ring zone of the surface of the plate, 3. the concentrated load applied at the center of the plate. By expanding the distribution of the contact stress between the plate and the half space into a series of the Jacobi polynomials, the problem is reduced to solve a system of simultaneous algebraic equations. The numerical results show that: when the rigidity of the plate is rat her large, the plate behaves like a rigid one, on the other hand, when the flexibility of the plate is rather large, the dynamic behavior of the plate is dependent of the type of the applied load.