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2019/6 Vol.122

【表紙の絵】
ソーラーケータイじゅう電システム

石井 智悠 くん(当時8 歳)

この前あつかったので、ケータイがあっつくなっていたので「そのねつをうまくつかってじゅうでんできたらな。」と思ったのでこの絵を描きました。

バックナンバー

論文アクセスランキング

日本機械学会学術誌(英文) 年間アクセス数トップ10

(2018年1月〜2018年12月の期間で集計)   

*順位の変動は2017年10月〜2018年9月の期間との比較


Large eddy simulation with modeled wall-stress: recent progress and future directions

Johan LARSSON, Soshi KAWAI, Julien BODART, Ivan BERMEJO-MORENO

Mechanical Engineering Reviews (2016) DOI:10.1299/mer.15-00418

The paper provides a brief introduction to the near-wall problem of LES and how it can be solved through modeling of the near-wall turbulence. The distinctions and key differences between different approaches are emphasized, both in terms of fidelity (LES, wall-modeled LES, and DES) and in terms of different wall-modeled LES approaches (hybrid LES/RANS and wall-stress-models). The focus is on approaches that model the wall-stress directly, i.e., methods for which the LES equations are formally solved all the way down to the wall. Progress over the last decade is reviewed, and the most important and promising directions for future research are discussed.


Prospect and Recent Research & Development for Civil Use Autonomous Unmanned Aircraft as UAV and MAV

Kenzo NONAMI

Journal of System Design and Dynamics(2007) DOI:10.1299/jsdd.1.120

This paper describes the present state of research and development for civil use autonomous unmanned aircraft. In particular, the history of civil use UAVs, the research and development in the world and in Japan, and the subjects and prospects for control and operation systems of civil use autonomous UAVs are described.


Effect of seam characteristics on critical Reynolds number in footballs

Kiyoshi NAITO, Sungchan HONG, Masaaki KOIDO, Masao NAKAYAMA, Keiko SAKAMOTO, Takeshi ASAI

Mechanical Engineering Journal (2018) DOI:10.1299/mej.17-00369

In recent years, the design of footballs, including the number and shape of the panels forming the surface of footballs, has undergone a significant change. However, panels of varied shapes and seams are combined in complex ways to form the surface shape of footballs, and almost nothing is known about the effect of these surface shapes on the football drag characteristics. The present study used a wind tunnel to study the relationship between the critical Reynolds number and the length, depth, and width of the panel joints (seams) of 10 most recent football types used in matches in recent years. The results show the tendency that the drag coefficient in the super-critical regime (30 m/s) of a football increases as the panel joint length increases. Moreover, the depth of the panel joint indicates the highest correlation with the critical Reynolds number (r = -0.71, p < 0.01) and is considered to be a strong and convenient indicator that expresses the roughness (large scale) of the football surface. This study reveals the drag characteristics of the latest footballs and enables some degrees of prediction of the critical Reynolds number for the latest football types and those that will be developed in the future.

4位

[→]

Micro Ball End Milling of Titanium Alloy Using a Tool with a Microstructured Rake Face

Toshiyuki OBIKAWA, Bunji KANI

Journal of Advanced Mechanical Design, Systems, and Manufacturing (2012)

DOI:10.1299/jamdsm.6.1121

5位

[↑]

Hydrodynamics of a self-propelled flexible fin in perturbed flows

Sung Goon PARK, Hyung Jin SUNG

Mechanical Engineering Reviews (2018)

DOI:10.1299/mer.17-00286

6位

[↓]

A Review on High-Speed Machining of Titanium Alloys

Mustafizur RAHMAN, Zhi-Gang WANG, Yoke-San WONG

JSME International Journal Series C Mechanical Systems, Machine Elements and Manufacturing(2006)

DOI:10.1299/jsmec.49.11

7位

[↑]

Effect of Fiber Length on Mechanical Properties of “Green” Composites Using a Starch-Based Resin and Short Bamboo Fibers

Hitoshi TAKAGI, Yohei ICHIHARA

JSME International Journal Series A Solid Mechanics and Material Engineering (2004)

DOI:10.1299/jsmea.47.551

8位

[NEW]

Direct numerical simulations of bubbly flows

Gretar TRYGGVASON, Jiacai LU

Mechanical Engineering Reviews (2015)

DOI:10.1299/mer.15-00220

9位

[NEW]

Cable-driven parallel mechanisms: state of the art and perspectives

Clément GOSSELIN

Mechanical Engineering Reviews (2014)

DOI:10.1299/mer.2014dsm0004

10位

[NEW]

Development of measurement technique of mass diffusion coefficient of aqueous methanol solutions in polymer electrolyte membranes based on infrared Soret forced Rayleigh scattering method using single crystal diamond window in a sample cell

Hiroaki MATSUURA, Daichi TOKUDA, Yuji NAGASAKA

Journal of Thermal Science and Technology (2018)

DOI:10.1299/jtst.2018jtst0015

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