Detonation Cell Widths in Hydrogen/Oxygen/Diluent Mixtures at Low Initial Pressures

Abstract

Detonation cell widths of hydrogen/oxygen/helium/steam mixtures were determined in 15 and 30-cm internal-diameter pipes using the smoked-foil technique. The investigations were carried out over a range of initial pressures from 13.3 to 106.6 kPa and at an initial temperature of 105°C. The concentration range investigated included hydrogen concentrations from 10 to 40 percent and steam concentrations of up to 20 percent. The measured cell widths range from about 1 mm to over 100 mm and were in good agreement with those estimated using the calculated values of induction times and post-shock gas velocities.