New Mazda 2.2L Diesel Features New DPF Technology

9 September 2008

Mazda’s new diesel incorporates a new Mazda-developed base material in the DPF that increases the regeneration speed. Click to enlarge.

Mazda Motor Corporation’s new 2.2-liter diesel, which will make its debut in the Kiyora concept (earlier post), features a Mazda-developed world-first catalyst activation mechanism that enhances the removal of particulate matter (soot) from the exhaust gases. (Earlier post.) The engine will be progressively introduced to markets around the world, beginning in Europe in 2009.

The MZR-CD 2.2 diesel engine has a displacement 10% greater than Mazda’s current MZR-CD 2.0-liter diesel, and delivers torque of 400 Nm (295 lb-ft). Improved fuel injectors and a lower compression ratio contribute to its enhanced fuel efficiency.

The 136 kW (182 hp) diesel has a fuel consumption rating of 5.6 L/100km (41 mpg US). The addition of a dual balance shaft and a more rigid engine block has resulted in a significant reduction in engine vibration, and helps achieve extremely quiet operation.

The new catalytic combustion treatment process enables the DPF to burn off particulate matter approximately 60% faster than current systems. Due to this technical advancement, the MZR-CD 2.2 is clean enough to qualify for the Euro 5 emissions standards. (This is based on a Mazda in-house assessment.)

The engine uses a high thermal resistance diesel particulate filter (DPF) with a catalyst that optimizes the combustion of soot in the exhaust. The activation mechanism, combined with more precise engine control, doubles the interval between DPF regeneration cycles, and reduces the time to complete the regeneration process to a third of the time necessary for conventional systems.

Catalysts use the oxygen contained in exhaust gases to burn off particulate matter. In order to initiate combustion, the temperature of the exhaust gas must be increased. This requires additional fuel, which adversely affects overall fuel economy.

The ceramic base material in Mazda’s catalyst has a molecular structure that enables the easy movement of oxygen stored within it. This extra oxygen can be supplied as required to significantly increase the rate of particulate matter combustion—effectivelyincreasing the DPF regeneration speed.

As a result, the new catalyst mechanism reduces the amount of fuel required to burn off the particulates (soot). This improves the overall fuel economy, and results in lower CO₂ emissions and cleaner exhaust gases.