In order to gain the distribution characteristic of pressure in same section of detonation tube
a series of single detonation experiments were conducted to study acetylene-air mixtures in square detonation tube.Four pressure transducers were installed respectively in different positions of two sections to measure the pressure value.The experiment was performed respectively in tube with/without obstacles.The results indicate that the size of pressure wave in same section is different and the detonation wave is not a plane wave.The pressure in tube wall is higher than that in tube center.