Volvo Trucks North America unveiled its previously announced new family of heavy-duty diesel engines—the 11-liter D11, 13-liter D13 and 16-liter D16—that meet the upcoming 2007 US emissions standards (earlier post).
Volvo Trucks North America will use high-performance cooled exhaust gas recirculation (EGR) and diesel particulate filters (DPF) to meet the new standards. The third component of the emissions reduction formula is the ultra-low sulfur diesel being introduced in North America in the fourth quarter of 2006.
(For Europe, Volvo’s new Euro-4 and Euro-5 engines use SCR (Selective Catalytic Reduction) for NOx control.)
Features of the new Volvo engines include:
Ultra High Fuel Injection Pressure (UHFP), with maximum fuel injection pressures raised 20% over the Volvo D12 to 35,000 psi (2,400 bar). The higher pressures improve fuel atomization and dispersal in the cylinder for more efficient combustion and lower emissions.
Multiple fuel injections per stroke, utilizing a new proprietary actuation strategy for the dual-solenoid unit fuel injector Volvo introduced on its 2002 Volvo D12. This gives extremely precise control over fuel injection for emissions control and engine performance.
Single-stage variable geometry turbocharger (VGT), with a sliding nozzle and electronic actuation. The VGT delivers enhanced engine response and driveability, as well as greater backpressure for the EGR system. The electronic actuator gives more precise control than a pneumatic actuator. Both the turbo bearing housing and the actuator are water-cooled. Volvo first introduced this technology on the D16 in 2005.
Increased peak cylinder pressures allows the engine to extract more energy from each drop of fuel.
Single-piece, rigid deck cylinder head with four valves per cylinder and 38 cylinder head fasteners is built to withstand the higher injection and cylinder pressures for increased durability and reliability. Like the engine block, the head is cast with proprietary technology in Volvo’s own foundry in Skövde, Sweden.
Rear-mounted gear train with camshaft damper drives the overhead camshaft, air compressor, and power steering pump. The viscous damper on the camshaft absorbs the torsional vibrations generated by high-pressure fuel injection and routes those vibrations into the flywheel, where they are effectively absorbed. This increases reliability and durability, and contributes to longer life for engine-driven components. Placing the gear train at the rear of the engine block also improves air flow and cooling around the engine.
Volvo VECTRO engine electronics with enhanced diagnostics builds on the established engine controls and extensive diagnostic capabilities of the previous generations of VECTRO. The VECTRO system also manages the communication between the delta-pressure EGR flow sensor and the VGT actuator and hydraulically controlled EGR valve.
Low-return, low-flow fuel system cools fuel in the engine, not the fuel tank, providing consistent fuel temperature to the injectors regardless of extreme summer heat or winter cold, for consistent power and better fuel economy.
Volvo Trucks will apply a $7,500 surcharge on invoices of new trucks built with the 2007 engines. The price increase includes Volvo trucks equipped with Cummins ISX engines, as well as Volvo D11, D13 and D16 engines. The surcharge covers the work that has been done to meet the 2007 requirements, including new technology for the engines, exhaust aftertreatment systems, cooling system enhancements and changes to electronic engine controls, according to the company.