Papers by Toshihiko Shakouchi
Lecture notes in mechanical engineering, May 15, 2018
Water or air-water bubble flow passing through tube bundle can be seen in many industrial equipme... more Water or air-water bubble flow passing through tube bundle can be seen in many industrial equipments such as heat exchanger and chemical equipment. In addition, tube bundle can be used as a flow-straightener, -mixer, -resistor, and -damping device. In this study, the effects of tube arrangement of equally or unequally spaced in-line and staggered tube bundle and of void fraction on the flow characteristics such as flow pattern and flow resistance of a tube or tube bundle are examined experimentally.
Springer proceedings in physics, 2016
Heat exchangers are widely used for heating, cooling, evaporation, and condensation. There are ma... more Heat exchangers are widely used for heating, cooling, evaporation, and condensation. There are many types of heat exchangers, shell and tube, fin tube, and double tube heat exchangers. Double tube heat exchangers show high performance, and several modifications have been made with regard to their pipe geometry to further improve their performance. A petal-shaped double tube with a large wetted perimeter is one such example. The working fluid of a heat exchanger for the evaporator and condenser of an air-conditioner or boiler may become a gas-liquid two-phase flow with phase change. In this study, the flow and heat transfer characteristics of airwater bubbly flow through a petal-shaped double tube with a large wetted perimeter are examined experimentally and compared with those of a conventional circular double tube. The experiments employed two petal-shaped double tubes: one with six petals and another with five petals. This study explains for single-phase water and two-phase air-water bubbly flows. The heat transfer characteristics are studied by measuring the temperature distributions in the inner and outer pipes by a thermo couple. The study also clarifies the effects of air bubbles on heat transfer performance.
Proceeding of Seventh International Symposium on Turbulence and Shear Flow Phenomena
Numerical solving of fluid-structure interaction (FSI) problems are of importance in various scie... more Numerical solving of fluid-structure interaction (FSI) problems are of importance in various scientific fields. In particular, the establishment of stable numerical scheme is needed in order to analyze the details of flow phenomena. In the present paper, we propose a weak-coupling method for FSI problem: for a elastic body the rigorous equations of motion are discretized with finite volume method; in the flow computation, the elastic body object is reproduced via immersed boundary method. To demonstrate the performance of proposed scheme, the 3D structure analysis and 3D FSI problems of a elastic body are solved. The results indicate that the computation is stably conducted using the proposed method, in spite of the occurrence of fairly large deformation of the object. In addition it turns out that the realistic flow including turbulence phenomena is well reproduce using the proposed FSI scheme.
The Proceedings of Mechanical Engineering Congress, Japan, 2019
Volume 3A: Fluid Applications and Systems, 2019
Multiple jets are used in industrial processes such as combustion, ventilation and so on, and the... more Multiple jets are used in industrial processes such as combustion, ventilation and so on, and their improvement of mixing and diffusion is demanded. Unlike single jet, since the jets issuing from nozzles will coalescence, merge or combine with each other, it is necessary to reduce mixing performance such as entrainment from surroundings and spreading into surroundings. It is well known that the characteristics such as mixing and diffusion of the jet are strongly dependent on the large-scale vortex structures being formed near the nozzles. Therefore, an appropriate inflow condition at a nozzle is capable of controlling the large vortex structures near field around the nozzle and improves the mixing performance. In this study, we examine an intermittent control of jets varying the control frequency and the jet spacing so as to reduce the interaction between each jet. We conduct the DNS (direct numerical simulation) of intermittently-controlled two round jets. In order to quantify the ...
The Proceedings of Mechanical Engineering Congress, Japan, 2019
The proceedings of the JSME annual meeting, 2003
Journal of the Society of Mechanical Engineers, 2007
The Proceedings of Conference of Tokai Branch, 2015
The Proceedings of Conference of Tokai Branch, 2016
The Proceedings of Conference of Tokai Branch, 2016
The Proceedings of Conference of Tokai Branch, 2016
The Proceedings of Conference of Tokai Branch, 2016
The Proceedings of Conference of Tokai Branch, 2016
The Proceedings of Conference of Tokai Branch, 2015
The Proceedings of Conference of Tokai Branch, 2013
The Proceedings of Conference of Tokai Branch, 2009
The Proceedings of Conference of Tokai Branch, 2005
The validation of Boussinesq Approximation in a gas − liqu董 d 且ow 正
The Proceedings of the Fluids engineering conference, 2013
The Proceedings of the Fluids engineering conference, 2009
CahI1 − HiUiard(CH)method is one of the interface − tracking method for tw (hphase flows ． An adv... more CahI1 − HiUiard(CH)method is one of the interface − tracking method for tw (hphase flows ． An advantage for CH method is that it can simulate complex behavior of interface relatively easily ． On the other hand ， the simulaition f(〕r twe − phase flows including fine d1sperse phase requiers more accuracy of interface − trackillg ． The accuracy of interface ． tracking due to diffusion by CH equation should be improved ． Hence， in the present paper ， the characte1 ・ istics of diffusion of order function by CH equation is invest1gated， We focus on the nlobility wllich mealls the anisotropic d 正 aracteristic 〔 ⊃f diffusion ill CH equatiol1 ， and evaluated accuracy of interface −tracking fbr 2D and 3D single rising bubble ．
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Papers by Toshihiko Shakouchi