Article Per Year (5 Year)
p-Index From 2021 - 2026
0.23
P-Index
This Author published in this journals
All Journal Scientific Contributions Oil and Gas
Yasuhito Nakatake
National Institute of Technology, Kurume College
Chemical Engineering, Chemistry & Bioengineering Energy

Published : 1 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 1 Documents
Search

 1 
Improvement of Operating Performance of Medium-Speed Marine Diesel Engines Using Marine Diesel Oil with Air Microbubbles Hideo Kawahara; Tomohiro Sunada; Yasuhito Nakatake; Koichi Terasaka; Hiroshi Kawahara; Hidechika Goto
Scientific Contributions Oil and Gas Vol 48 No 4 (2025)
Publisher : Testing Center for Oil and Gas LEMIGAS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29017/scog.v48i4.1908

Abstract

Marine diesel engines are widely adopted as the main auxiliary engines in ships because of their ability to utilize inexpensive heavy fuel oil and their high thermal efficiency per unit engine. This study focuses on practical marine medium-speed diesel engines to investigate the impact of introducing air as fine bubbles into low-sulfur A heavy fuel oil on the operating performance. The results indicated that when fine bubbles were introduced into the fuel, the engine exhibited poor combustion and became unstable at any load when Qa was 0.4 L/min or higher. However, when Qa was below 0.4 L/min, the fuel efficiency improvement increased significantly with increasing load, reaching a maximum reduction of 4.5% at 75% load and Qa = 0.3 L/min. Regarding the exhaust gas characteristics, at low loads, no significant changes were observed in the CO2 and NOx emissions with varying microbubble injection levels. However, at loads of 75% or higher, both the CO2 and NOx emissions decreased as the microbubble injection level increased. Furthermore, introducing fine bubbles into the fuel promoted atomization after fuel injection, similar to the results for heated C heavy oil, leading to improved heat generation rates across the entire engine load range.
Co-Authors Hidechika Goto Hideo Kawahara Hiroshi Kawahara Koichi Terasaka Tomohiro Sunada