The goal of HDGas is to provide breakthroughs in LNG vehicle fuel systems, natural gas and dual fuel engine technologies as well as aftertreatment systems. The developed components and technologies will be integrated into three demonstration vehicles that are representative for long haul heavy-duty vehicles in the 40 ton range. The demonstration vehicles will:

• comply with the Euro VI emission regulations;

• meet at minimum 10% CO₂ reduction compared to state-of-the-art technology;

• show a range before fueling of at least 800 km (497 miles) on natural gas; and

• be competitive in terms of performance, engine life, cost of ownership, safety and comport to 2013 best in class vehicles.

Three HDGas engine concepts/technology routes are being developed:

• A low-pressure direct-injection spark ignited engine with a highly efficient EGR system (the IVECO engine with GD Tech injectors);

• A low-pressure port-injected dual fuel engine;

• A high-pressure gas direct-injection diesel pilot ignition gas engine.

HDGAS will develop all key technologies up to TRL6/7.

Two scenarios were considered during the design phase of the DI-CNG injectors, resulting in different injector specifications:

• Scenario #1 injectors deliver a flow rate equivalent to the engine full load at 50 bar operating pressure and 180 crank angle degrees equivalent injection windows.

• Scenario #2 injectors deliver the full load flow rate at 20 bar operating pressure and 180 crank angle degrees equivalent injection windows.

The max engine speed considered is 2300 RPM; intermediate pressure levels can also be reached for the engine intermediate load points. These injectors can be controlled with a dedicated driver from 18V to 24V (with or without peak voltage).

All development was completed by GDTech Powertrain team. Manufacturing required more than 20 different suppliers (for machining, welding, winding, material supply, internal components supply, and various treatments).

The direct-injection of natural gas allows advanced features such as:

• engine scavenging (for low-end torque enhancement);

• engine stoichiometric operation: 18-21% potential CO₂ improvement compared to Gasoline Direct Injection;

• engine lean-burn operation: 23-26% potential CO₂ improvement compared to Gasoline Direct Injection, as well as 60% NO_x reduction & 85% CO reduction (values proven at the test bench on a 1.6L turbocharged gasoline-based wall-guided engine); and

• multi-injection: 15% THC potential improvement compared to single-injection.

GDTech has led R&D projects in the field of DI-CNG passenger-car engines (with the support of Wallonia Research Directorates) since November 2008.

Several injector concepts have already been developed proven on passenger-cars engines. A demo Peugeot 508 equipped with a DI-CNG converted engine is being tested on the dyno to meet Euro 6 emissions targets.

GD Tech has filed a patent to protect several points of the injector design. As a next step, these injectors will now be tested in single-cylinder test campaigns.