Valve Gear Simulation by Dr. Allan Wallace PhD Mech Eng

Dr Allan Wallace (PhD in mechanical engineering and fluid mechanics) runs his own engineering consulting company Avocet Consulting Pty Ltd in Adelaide, South Australia, that specialises in solving unusual and difficult engineering problems. Allan has undertaken several railway-related projects including the design of specialized rail freight wagons.

Like Richard Coleby, Allan is an enthusiastic builder of miniature (3½” and 5″ gauge) steam locomotives which he regularly runs in his spare time. He has also built a 5″ gauge dynamometer car fitted with electronic load-cells and lap-top computer, for monitoring and comparing the performance of his and other builders’ locomotives.

In association with his locomotive modelling, Allan has developed several valve gear simulation software suites that he makes available from his website at http://www.avocetconsulting.com.au/modeleng/.

Allan has given valuable assistance to David Wardale in the preparation of his Fundamental Design Calculations FDC 5 covering the valve-gear for the 5AT by adapting his own Walschaerts valve gear program to accommodate the 5AT’s unusual suspended combination lever (required to activate the twin valves above each of its cylinders).

Allan lives in Adelaide, Australia.