MEKANISME PERAMBATAN GELOMBANG DETONASI DI BELAKANG PLAT DENGAN ORIFIS GANDA (Propagation Mechanism of Detonation Wave Behind Plate with Double Orifices)

• Main Authors: , RIZQI FITRI NARYANTO, ST., , Dr. Eng. Jayan Sentanuhady, S.T., M.Eng.
• Format: Theses and Dissertations NonPeerReviewed
• Published: [Yogyakarta] : Universitas Gadjah Mada 2011
• Subjects: ETD
• Online Access: https://repository.ugm.ac.id/88680/; http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=51017
• Institution: Universitas Gadjah Mada

On detonation wave propagation system, a combustion wave and a shock wave always propagate in the coupling conditions at supersonic velocity. Shock wave which has a high pressure would be harmful to human safety if an accident detonation occurred. By to know the limits of detonation, the detonation accident can be avoid or minimized by change the detonation wave into deflagration wave by using the orifice in the channel potential detonation accident. In this experiment, a premixed fuel hydrogen gas with oxidizer of oxygen mixed in stoichiometric condition is use to the fuel. Fuel mixture is tested in a circular horizontal detonation test pipe with 50 mm inner diameter and 6,000 mm long, at room temperature and initial pressure in the driver tube is 100 kPa to ensure the process of detonation in the driver and the upstream in part of driven. In this experiment by varying the pressure in the driven tube (test tube) from 20 kPa up to 100 kPa and using a test model. The test model is a plate with double orifices, made of aluminum with 10 mm thickness, witch a double orifice hole diameter w is 5 mm, 7 mm, 10 mm and the distance between hole of orifice is twice of the orifice. The results show that the character of propagation detonation behind the plate model with double orifices in the downstream area can be classified into three patterns of propagation: the first is Detonation Re-initiation, where divided into two categories: (a) Re-initiation by Shock-Wall (S-W), (b) Re-initiation by DDT mechanism (DDT), the second is Detonation Transmission, which detonation propagates without failure, the third is Quenching Detonation, which wave propagates as deflagration wave. Detonation Re-initiation behind the plate with double orifices will occur faster if inisiated by the shock wave interaction, when the number of detonation cells inside the orifice is less than 4λ, the detonation wave will be re-initiated by DDT mechanism, and if the number of detonation cell inside orifice is more than 4λ there will be re-initiated by mechanism of Shock-Wall (S-W). Re-initiation Detonation with mechanism Shock- Wall (S-W) will be success to occurs when the shock wave pressure is greater than18.3 the initial pressure.