The Oxford Cold Driven Shock Tube (CDST) for fuel spray and chemical kinetics research

A new reflected shock tube facility, the Cold Driven Shock Tube (CDST), has been designed, built and commissioned at the University of Oxford for investigating IC engine fuel spray physics and chemistry. Fuel spray and chemical kinetics research requires its test gas to be at engine representative pressures and temperatures. A reflected shock tube generates these extreme conditions in the test gas for short durations (order milliseconds) by transiently compressing it through a reflected shock process. The CDST has been designed for a nominal test condition of 6 MPa, 900 K slug of air (300 mm long) for a steady test duration of 3 ms. The facility is capable of studying reacting mixtures at higher pressures (up to 150 bar) than other current facilities, whilst still having comparable size (100 mm diameter) and optical access to interrogate the fuel spray with high speed imaging and laser diagnostics. Future data gathered will support fundamental research for IC engine and fuel technologies leading to even higher thermal efficiency along with a reduction in emissions, and provide high quality, repeatable validation data for advanced model development. This paper describes the scope of the facility's capabilities, aspects of its design, details of the instrumentation, and the axially mounted single hole diesel injector.