The Hydrogen-Engine section of the Engine Combustion Network contains data from Sandia’s optical hydrogen engine (SOpHy).

Measurements center on operation with direct fuel injection, focusing on fuel-air mixing during the compression stroke. This section provides the information necessary to set up a numerical simulation of the in-cylinder processes in the engine and laser-based measurements to validate such simulations.

The engine is a passenger-car sized, four-stroke single-cylinder research engine, adapted to operate with hydrogen. Large transparent segments make the engine optically accessible for laser-based measurements. The engine geometry is typical for modern car engines: 4 valves and pent-roof. The piston top is flat without valve cut-outs.

The crank-angle convention used in this web site assigns 0°CA to compression TDC, i.e., crank-angles during the compression stroke are negative.