Digital engineering for Tier 4

With the final phase-in of the U.S. EPA Tier 4 emissions standard set to take effect by 2015, off-highway engine developers are accelerating product introductions. Design challenges remain for manufacturers even after the final phase-in while CAE software providers improve technology.

Off-highway powertrain developers have a host of attributes to balance, including cost, weight, power, adaptability, and fuel economy. While all are important, some have more wiggle room than others. Not so with regulatory emissions standards: “You either meet emissions or you do not,” said Chris Mays, Project Director, Engines Product Group for Ricardo Engineering in an interview with SOHE.

Beyond that hard limit, though, there are a number of design variables for engineers to agonize over. Mays should know-his company has helped engineer a number of off-highway power-plants such as JCB's EcoMaxT4 4.4-L engine and another for Lombardini in the <bold>Look for more integration of CAE models, both to reduce engineers' workload and better understand whole systems. Ricardo Software provides tools for combustion, thermal, and structural analysis of engines.</bold> <bold>FORTÉ simulation of low-temperature combustion in a heavy-duty diesel. (Reaction Design)</bold> KDI family (KDI1903TCR and KDI2504TCR). “[Engineers] can play with trying to remove emissions at the source-in the engine-vs. adding more aftertreatment devices,” he continued. DPFs remove particulate matter or soot (PM); SCR devices or NOx adsorbers remove NO and NO₂. Each choice requires refinement. “Every OEM has a different play on how to handle the trade-off among those different variables,” he said. “For instance, in the case of the Lombardini engine, we were able to engineer out the need for a DPF and still meet the standards for both Tier 4 interim and final.”