What regulators take away, engineers have to put back better

A marriage of electronic control and hydraulic power is helping OEMs and end-users maintain traditional diesel efficiency while meeting ever more stringent emissions requirements.

Global emissions regulations are driving a virtual explosion of new technology in the diesel industry as OEMs scramble to comply with a series of mandates scheduled to take effect through 2013. Whether it's U.S. EPA Tier 3 and 4 or EU Stage III and IV in Europe and much of Asia, the new requirements are forcing engine builders to re-think every aspect of their product from the basic combustion process itself to all of the subsystems that support the engine.

One place this re-thinking has shown up is in the cooling system. What used to be simply a radiator and belt-driven, or shaft-mounted, fan is being transformed into a programmable “thermal-management” or “cooling-on-demand” system on today's advanced diesels.