Design and Development of the Holset HX Series of Turbochargers

Engine development programs in general, and US exhaust emmisions legislation in particular have provided a challenge for turbomachinery suppliers, with requirements for higher boost pressures at low engine speeds and improved transient response. This must be achieved whilst maintaining or improving steady state aerodymnamic performance, reliability, durability and cost competitiveness.

This paper discusses design issues, and describes some of the methods used, to create the first two models of a new range of turbochargers to meet the changing needs of automotive diesel engines in the 1990's.