Suitability of Using the Accelerometer for Impulse Measurement of a Pulse Combustion Tube

An experimental study of impulse produced by a pulse combustion tube was done to compare between the methods of pendulum and accelerometer for impulse measurement. Stoichiometric mixtures of methane and propane were studied with varying dilution percentages of Nitrogen. Without obstacles, all mixtures exhibit deflagration. To induce detonation, obstacles were used. Detonation occurred for dilution percentage of 42% and lower. From the results, pendulum method always gives higher impulse measurement in deflagration regime while the accelerometer method gives higher results for detonation. The accelerometer method is not suitable for deflagration due to inaccuracies in determining pressure peaks from the measurement. However, it is suitable for studying individual pulses in detonation due to the presence of distinct pressure peaks.