Volvo Construction Equipment’s new D11 engine has been granted Tier 4 emissions certification by the EPA (Environmental Protection Agency). Engines which fall within the 175-750 hp class are to be bound by the Tier 4i emissions regulations from the 1st of January 2011, and that requires radical decreases in both diesel particulate matter, which must be reduced by 90 percent, and nitrogen oxide, which must be reduced by 50 percent.
The new Volvo D11 engine, now certified by the EPA, is equipped with V-ACT, or Volvo Advanced Combustion Technology, which features variable fuel injectors operating at extremely high pressure, as well as supercooled EGR (Exhaust Gas Recirculation)systems. The turbocharger controls are VGT (Variable Geometry Turbo), and the exhaust after-treatment is integrated and utilises a thermal regenerator and a sensitive particulate filter.
John Bartz, the Director of Product Assurance and Regulation for Volvo Construction Equipment North America, said:
Volvo Construction Equipment is meeting the emission requirements of the new standards by continuing to engineer and develop engines of the highest quality and reliability and with the greatest performance and productivity accomplishments on the market today.
The bets results from the advanced engineering of the D11 is in conjunction with the other aspects of the Volvo powertrain, which leads to effective combustion efficiency, which in turn leads to greater power capacity, lower fuel consumption, lower emissions and increased cost effectiveness.
Volvo has plenty of experience developing engine solutions which meet various pieces of EPA legislation, as they have already implemented such technology in the their Volvo trucks line, in line with the EPA’s on-highway regulations of 2007. The off-highway solution has been tested under the equivalent of millions of hours, and a variant may soon be ready for vehicles such as their backhoe loaders, allowing them to rival the classic JCB 3cx for sale.
The new engine is highly engineered, with electronic controls, and the V-ACT system, combining to deliver control, engine management and torque of the highest quality. The EGR (Exhaust Gas Recirculation) system reduces the production of nitrogen oxide significantly, easily enough to meet the 50 percent reduction guidelines required by Tier 4 regulations. It does this by recirculation, which reduces the level of oxygen present in the combustion chamber. This, in turn, reduces the temperature during combustion, and this prevents significant formation of NOx. The system is made possible by the use ultra-low sulphur fuel. Another requirement of Tier 4 is huge reductions in particulate matter. The new Volvo after-exhaust treatment system achieves this by catching particulate matter in a specialised filter, wherein the particles are oxidised, or ‘regenerated’, which removes them.
The use of Ultra Low Sulphur diesel is also stipulated by the Tier 4 regulations, and it contains 15ppm of sulphur, a huge reduction from 500ppm.
Due to the sophisticate level of engineering inherent in the new D11 Tier 4 compliant engine, a high level Engine Management System (EMS) was necessary, and this is exactly what has happened. The EGR is controlled by the electronic system, which coordinates the complex re-circulations.
Bartz stated:
The newly EPA-certified Volvo engine will dramatically demonstrate the decades of engine technology (begun in 1893) that has made Volvo Construction Equipment one o