日本機械学会サイト

目次に戻る

2020/6 Vol.123

表紙の説明:これは、出力10万kWレヒートガスタービンの高圧圧縮機部分である。1978年から10年間、通商産業省工業技術院のムーンライト計画(省エネルギー技術研究開発)の中で開発されたもので、全長21mある。東京電力袖ケ浦発電所に設置して運転研究の結果、総合熱効率52%を得た。
[日本工業大学工業技術博物館]

表紙写真 北原 一宏

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

(2019年1月~2019年12月の期間で集計) *順位の変動は2018年10月~20199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.

Investigation of the mechanism of the indentation size effect for titanium

Shota HASUNUMA, Hirohisa MIYAZAKI, Takeshi OGAWA

Mechanical Engineering Journal (2019) DOI:10.1299/mej.18-00545
In this study, we investigated the mechanism of the indentation size effect for Ti, whose crystal structure is hexagonal close-packed. Indentation tests were performed for two types of single-crystal Ti with different crystal orientations: (0001) and (1120). Indentation tests were also performed with different indenter directions. The hardness depends on the crystal orientation and indenter direction because Ti has large anisotropy. The shape of the impression also changes with the crystal orientation and indenter direction. The hardness increases with decreasing penetration depth for the (0001) and (1120) orientations, so the indentation size effect occurs. For the (0001) orientation, a sudden rapid increase in displacement occurs during indentation tests owing to twinning. This sudden rapid increase in displacement causes a rapid decrease in the hardness. Electron backscatter diffraction was performed around the impressions to measure the geometrically necessary (GN) dislocation density. The GN dislocation density increases with decreasing penetration depth for the (0001) and (1120) orientations. This trend corresponds to strain gradient theory. The reason for the indentation size effect in Ti is the increase in the GN dislocation density. For the (0001) orientation, the indentation size effect also can be attributed to twinning. Considering both our previous study and this study, the experimental results correspond to strain gradient theory in many cases.

4位

[↑]

Customization of product, service, and product/service system: what and how to design

Tatsunori HARA, Tomohiko SAKAO, Ryo FUKUSHIMA
Mechanical Engineering Reviews (2019) DOI:10.1299/mer.18-00184

5位

[↑]

Development of tunnel compression wave generator with multiple small solenoid valves

Tokuzo MIYACHI, Takakage ARAI, Shoji SAKAUE, Koji TAKASHIMA, Daiki TANIKAWA, Takuya YAGISHITA, Kento NAKATANI
Mechanical Engineering Journal (2019) DOI:10.1299/mej.18-00478

6位

[NEW]

Running position matching for the monitoring bogie and temporal subtraction analysis of derailment coefficient

Yosuke ICHIYANAGI, Yohei MICHITSUJI, Akira MATSUMOTO, Yasuhiro SATO, Hiroyuki OHNO, Seigo OGATA, Masuhisa TANIMOTO, Atsushi IWAMOTO, Tomoki FUKUSHIMA, Takuji NAKAI
Mechanical Engineering Journal (2019) DOI:10.1299/mej.18-00426

7位

[NEW]

Estimation method of interfacial stiffness of bolted joint in multi-material structure by inverse analysis

Yoshinao KISHIMOTO, Yukiyoshi KOBAYASHI, Toshihisa OHTSUKA, Akira MATSUMOTO, Motoi NIIZUMA
Mechanical Engineering Journal (2019) DOI:10.1299/mej.18-00471

8位

[NEW]

Development of flow-accelerated corrosion prediction method (2) Modeling and validation with thinning rate profile data

Kimitoshi YONEDA, Kazutoshi FUJIWARA, Ryo MORITA, Fumio INADA
Mechanical Engineering Journal (2018) DOI:10.1299/mej.17-00415

9位

[↓]

Electromagnetic damper using brushless direct drive DC motor

Taichi MATSUOKA
Mechanical Engineering Journal (2018) DOI:10.1299/mej.18-00307

10位

[NEW]

Mechanical and thermal expansion properties of aligned carbon nanotube reinforced epoxy composites

Keiichi SHIRASU, Itaru TAMAKI, Go YAMAMOTO, Toshiyuki HASHIDA
Mechanical Engineering Journal (2019) DOI:10.1299/mej.19-00012

キーワード: