Ford’s latest range of EcoBlue diesel engines are set to debut in in commercial vehicles later this year, before the application range is expanded to Ford’s passenger cars. With power outputs ranging from 100PS to 240PS, the new four-cylinder 2.0-litre Ford EcoBlue is said to offer improved fuel efficiency, performance and refinement over the outgoing 2.2-liter engine.
An all-new compact turbocharger has been designed to deliver more air at lower engine rpm compared with the outgoing 2.2-litre TDCi engine, and results in the new engine producing 340Nm of torque at 1,250rpm, a 20% improvement over its predecessor.
The compact nature of the turbocharger has seen a number of innovations in its design and manufacture. A much smaller Inconel turbine wheel is used in tandem with a ‘downsized’ compressor wheel to decrease inertia and faster spool times for the turbocharger, which maxes 240,000rpm.
“One important factor we noticed through customer feedback is a growing tendency for drivers to ‘creep’ their diesel powered vehicles by engaging the clutch while the engine is at idle making low-down torque even more essential,” said Paul Turner, base engine technical leader, Ford of Europe.
The compressor wheels are milled from solid, rather than cast, improving tolerances to within two or three microns. A new turbocharger actuator replaces a worm drive with a geared design that halves response times to 110 milliseconds.
The all-new engine architecture utilizes a 10mm offset crank design that minimises piston side-load, reducing the frictional rubbing forces against the cylinder walls of the downsized four-cylinder iron block. In addition to this, Ford also minimised the crankshaft bearing diameters, added a belt-in-oil design for the camshaft and oil pump drive belts, and created an all-new single-piece camshaft module. Ford is also keen to state that for the first time, it is using a new mirror-image porting design for the integrated inlet manifold. This precisely controls the flow of air into the cylinders with the clockwise airflow for cylinder numbers one and two, reversed for cylinder numbers three and four.
This symmetrical arrangement ensures an equal mixing of fuel and air in the combustion chambers of all four cylinders. When fine-tuning the combustion process, computer experiments used measurements from more than 1,400 factors that affect performance of the valve lift and timing alone.
“Our first ever mirror-image inlet design in combination with an optimised combustion chamber layout helps us turn fuel into energy more effectively than any diesel engine we’ve ever produced,” added Dr. Werner Willems, Ford technical specialist, Combustion Systems.
The EcoBlue also makes use of all-new fuel injectors. These new items are capable of delivering up to six injections per combustion event, with each injection taking as little as 250 microseconds (0.00025 seconds) and delivering 0.8mg of diesel through eight conical holes each 120 microns in diameter.
As mentioned, the 2.0-litre Ford EcoBlue engine will be the first diesel commercial vehicle powertrain from Ford to achieve passenger car noise, vibration and harshness criteria, contributing to enhanced driving appeal.
The new engine radiates half as much sound energy at idle as the 2.2-litre TDCi diesel engine, which is ensured thanks to a revised cylinder-head, block, stiffening ladder-frame and an oil pan specifically developed to be desensitised to activity inside the engine, whilst non-flat mating surfaces have been designed to offer tight seals to ‘trap’ noise within the engine.
“The basic structure of an engine can act as a soundboard for the movements happening inside it, just like a bell. So we try to develop a bell that does not ring very well,” said Dominic Evans, NVH specialist, Ford of Europe. “We’ve engineered every significant noise-influencing component of this engine to be quieter and smoother operating resulting in the most refined diesel commercial vehicles Ford has ever built.”
The engine’s performance has been trialled through the equivalent of 3.4m miles of durability testing including 250,000 miles at the hands of real-world customers, comprehensive analysis in laboratories and at Ford vehicle proving grounds, and CAE evaluations at every stage of development.
“We developed the 2.0-litre Ford EcoBlue engine using feedback from customers around the world,” concluded Paul Turner. “The versatile design even allows the same block to be used for front-wheel drive and rear-wheel drive applications, and the sophisticated design and technologies deliver future-proofed fuel efficiency and emissions.”
