MAN Diesel Turbochargers for Tier II Compliance

Wednesday, May 20, 2009

The Business Unit Turbocharger at MAN Diesel has recently announced that its complete ranges of TCA axial and TCR radial turbochargers are available for both two and four-stroke engines complying with IMO Tier II emissions legislation. Indeed, the Augsburg-based engine and turbocharger specialist stresses, the requirements of IMO Tier II engines were designed into the TCA and TCR turbochargers from the first.

Importantly, to eliminate additional work for engine builders, the new, higher performance IMO Tier II turbocharger versions from MAN Diesel retain the same external and connection dimensions as versions for IMO Tier I compliant engines. In this way, no changes are needed to the existing turbocharger mounting arrangement when upgrading an ongoing engine series to IMO Tier II compliance.

The major change with the IMO Tier II versions of TCA and TCR turbochargers has been to increase pressure ratios to enable Miller cycles of varying intensity as a means of substantially reducing the formation of oxides of nitrogen (NOx). On four-stroke engines this involves closing the inlet valve early to allow the incoming air to expand and cool and thus eliminate the combustion temperature peaks responsible for the majority of NOx formation. On low-speed, two-stroke engines the same effect is achieved by reduction of compression volume, increased scavenging air pressure and late closing of the exhaust valve, in some cases combined with optimisation of the fuel system.

Higher pressure turbocharging ensures that an equivalent amount of air enters the cylinder, thus leaving engine power, torque and response unaffected. For two-stroke engine applications MAN Diesel reports that the necessary increase in pressure ratio is achieved exclusively via minor changes to the internal flow components of the turbochargers. On the four-stroke side, the new high-pressure turbocharger versions feature a revised design of compressor wheel with enhanced performance, as well as a number of further internal revisions.

Maritime Reporter November 2014 Digital Edition
FREE Maritime Reporter Subscription
Latest Maritime News    rss feeds

Marine Propulsion

Royal Caribbean to Install Scrubbers on 19 Ships

Royal Caribbean Cruises Ltd. (RCL) will retrofit 19 of its ships with advanced emissions purification (AEP) systems. These systems, also known as scrubbers, will

Wärtsilä to Power LNG-fuelled RoPax Ferry

A new passenger ferry being built for Swedish operator Rederi AB Gotland will be fuelled by liquefied natural gas (LNG) and will feature a Wärtsilä integrated solution.

Keeping to the Schedule in the Pacific Northwest

When a tightly scheduled repower for the Kodiak-based trawler Sea Mac in early December took a very bad turn, Mike Fourtner used his 25 years of fishing experience

 
 
Maritime Careers / Shipboard Positions Naval Architecture Navigation Offshore Oil Pipelines Port Authority Ship Electronics Ship Repair Ship Simulators Winch
rss | archive | history | articles | privacy | terms and conditions | contributors | top maritime news | about us | copyright | maritime magazines
maritime security news | shipbuilding news | maritime industry | shipping news | maritime reporting | workboats news | ship design | maritime business

Time taken: 0.2207 sec (5 req/sec)