Performance Development Strategies for a Two Cylinder Naturally Aspirated Common Rail HSDI Engine

Stringent emission regulations on one hand, and increasing demand from the customer for better drivability, NVH and fuel economy on the other, call for the adoption of advanced common rail technologies even in the commercial vehicle segment that is typically dominated by mechanically governed engines. Common Rail Direct Injection has traditionally been the forte of the passenger car and Sports Utility Vehicle (SUV) segment, and the benefits have been accorded to the premium segment users. The present work is undertaken in an attempt to downsize larger common rail direct injection engines for use on a 0.85 tonne load carrying platform, bringing the advantages of this technology to a wider section of users, while keeping the cost at a comparable level with mechanically governed engines.

This work describes the strategies adopted to accomplish the performance targets on a 0.9l two cylinder naturally aspirated common rail engine. Calibration of a two cylinder common rail engine presents a unique set of challenges from the fuel and air system matching perspective. The present paper describes the optimization of injection strategies to achieve power and torque targets without compromising on fuel consumption and emissions, and hardware selection for optimum performance with a low cost.