Some measurements of flame speeds in pipes

A detection method, using ionisation sensors and a digital storage oscilloscope, was developed to measure flame speeds in a 51 mm 1.0. mild steel pipe. Using a spark ignition, the system could only measure slow flames due to premature triggering of the oscilloscope by the spark. Flame speeds of 99 ms-1 and 145 ms-1 for 1.45 m and 2.45 m run-up lengths were recorded. [Continues.]