DEVELOPMENT OF A LOW-NOX TRUCK HYDROGEN ENGINE WITH HIGH SPECIFIC POWER OUTPUT

The charged hydrogen engine with internal mixture formation as part of the HYPASSE (Hydrogen Powered Automobiles using Seasonal and weekly S urplus of Electricity) project will be presented. With direct hydrogen injection it is possible to solve the problems of hydrogen engines wi th external mixture formation. Those problems are knocking, glow ignit ion during compression stroke and backfiring past the intake valve. Wi th the internal mixture formation system, the volumetric efficiency an d the power output is equal to that of a diesel engine. To obtain low NOx emissions it is necessary to operate the H-2-engine at excess air ratios lambda greater than or equal to 2 by means of turbocharging. Th e discrepancy between late high-pressure injection together with diffu sion flame propagation and early injection, i.e. to obtain a more homo geneous internal mixture formation, is studied by operating a single c ylinder research engine. (C) 1997 International Association for Hydrog en Energy.