Improving Engine Performance
Peter M Guerra – VP Technology
To realize the benefits of today’s cleaner-burning ULSD fuels and advanced High Pressure Common Rail (HPCR) injection systems, new diesel detergent technology is required to maximize performance. In order for HPCR injection systems to efficiently produce more power and reduce emissions, the fuel is stored in a central accumulator rail under extremely high pressure (25,000 to 30,000 psi). The fuel is delivered to each electronically controlled injector to provide up to 6 injection events of atomized fuel per combustion cycle. HPCR injection systems provide significant performance improvements as a result ofmore specific internal tolerances (2-3 microns) and higher injection pressures. HPCR diesel injection systems provide quieter, more efficient diesel engine performance, but as with most new technologies, HPCR has created new operational challenges for the diesel engine operator. The operational challenge for HPCR injection systems is Internal Diesel Injector Deposits. These deposits are different and distinct from conventional nozzle deposits as they are produced primarily in the injector valve seat but can also be found in the nozzle areas of HPCR injectors.
Deposits are found as a result of injector temperatures that exceed 350°F., thus causing a chemical reaction between corrosion inhibitors and sodium or calcium, commonly found in ULSD at low parts per million levels. Internal Diesel Injector Deposits result in a slow response or sticking of moving internal parts, resulting in a loss of injection event timing and variances in the amount of fuel delivered to the cylinder. A slow or sticking injector response causes excess fueling into the cylinder, resulting in increased emissions, decreased fuel economy and excessive power loss.
|A HPCR injection system productes power more efficiently by storing fuel on an accumulator rail under extremely high pressure (25,000 – 30,000 psi) to finely atomize fuel droplets.||Internal Diesel Injector Deposits (IDIDs) are produced in the injector valve seat and nozzle areas due to exteme heat.|
To address internal diesel injector deposit formations in HPCR injection systems, an engine test was needed to replicate in-field issues experienced by Original Equipment Manufacturers (OEMs). In March 2008, the CEC (Coordinating European Council) approved the F-98-08 DW10 Injector Fouling Test. The DW10 test uses a Peugeot DW10 2.0-liter, 4-cylinder, direct-injection turbocharged engine that is representative of new future diesel engine design. It directly measures engine power, which is a function of the level of injector fouling. The DW10 test provides a benchmark for evaluating the effectiveness of injector deposit control additives to both prevent and rapidly remove internal diesel injector deposits. This new test method has significantly increased the deposit control requirements of diesel detergent in comparison to the previous L-l0 and CEC XUD-9 test methods.
The FPPF Fuel Stabilizer and Diesel Injector Cleaner’s ‘onew” detergent technology has recently been tested using the DWl0 procedure and has proven effective in both preventing and removing the injector deposits from HPCR injectors. These additives have shown to provide complete power recovery losses in the DW10 Diesel Fuel Injector Fouling Test in as few as 16 cycles. FPPF diesel fuel additives prevent power loss and eliminates internal diesel injector deposit formations, to provide diesel engine operators immediate improvements in fuel economy and power that will more than pay for the cost of the fuel additive.