RE-INISIASI DETONASI DI BELAKANG PLAT DENGAN ORIFIS GANDA 7 MM

Abstract

Detonation waves are the combustion reaction waves that propagate at supersonic speeds. The phenomenon of detonation waves that have failed due to the diffraction process which can re-initiatited was back into a detonation wave, interesting to understand that this problem related to the safety of hydrogen gas. This study aims to understand of failure mechanisms and re-initiation of detonation wave behind the plate with double orifices 7mm. This experiment use a Detonation Test Pipe (DTP) with 6 meters length, DTP is divided into two parts, namely 1 meter for the driver test pipe and 5 meters to the driven test pipe. Aluminum plate with double orifices diameter of 7 mm and the distance between the orifices 14 mm,10 mm thickness on the driven test at 5 meters distance from the ignition point. Two mechanisms re-initiation behind the detonation wave propagation test models can be classified as follows: (1) Re-initiation detonation by DDT in down stream area. (2) Re-initiation detonation by shock-wall, re-initiation detonation by interaction between wall pipe and shock wave. Quenching detonation (deflagration) observed at initial pressure of 20kPa, while the initial pressure of 30 - 60kPa re-initiation detonation occurred in the presence of DDT process in the downstream. Re-initiation detonation wave due to interaction between shock wave with the inner wall pipe occurs at the initial pressure of  70-100kPa characterized by the formation of fine smaller detona-tion cells. To guaranty to make quenching detonation (deflagration), pressure must be in the low pressure at 20kPa to design detonation arrester.