FENOMENA DIFRAKSI GELOMBANG DETONASI PADA CAMPURAN BAHAN BAKAR HIDROGEN-OKSIGEN DENGAN DILUENT ARGON

• Main Authors: , BAMBANG PUGUH MANUNGGAL, , Dr.Eng. Jayan Sentanuhady, S.T.,M.Eng
• Format: Theses and Dissertations NonPeerReviewed
• Published: [Yogyakarta] : Universitas Gadjah Mada 2012
• Subjects: ETD
• Online Access: https://repository.ugm.ac.id/99130/; http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=55186
• Institution: Universitas Gadjah Mada

The supersonic combustion, shock wave and reaction wave propagates in coupled condition. The hight pressure of shock wave that can reach 20 times of initial pressure would be harmful to human safety of an detonation. The study of detonation reinitiation is a real important view to design detonation arrester that could be used to eliminate the detonation propagation. Expansion process as a result of diffraction phenomenon can cause the sustained propagation of detonation wave failure, so that shock wave and reaction wave will be decouple and propagation velocity declines become subsonik (deflagration), where is this condition easier to be controlled and not too dangerous.The way to converts detonation wave to be deflagration wave through diffraction phenomenon is serve to be basic method to design detonation arrester.This experiment used facing step to generated the diffraction phenomenon. This experiment used horizontal circular pipe which having 50 mm inside diameter and 6300 mm length. The fuel is premixed mixture of hydrogen and oxygen stoichiometry condition with 20% agron diluents and the initial pressure condition would be variated from 10 kPa up to 100 kPa. After propagates through narrow gap, the detonation wave will be diffracted and then would be investigated related to the detonation reinitiation. The result show that characteristic of detonation wave propagation behind narrow gap is classified to three propagations, (a) Detonation transmission, the detonation wave propagation without the quenching process, (b) reinitiation of detonation, deflagration to detonation transition (DDT) process and reinitiated by interaction of shock wave with inside pipe wall in the downstream region (c) Quenching detonation, the detonation wave is not reinitiated in the region of observation.The effect of the facing step model variation was seen to be very dominant in the ring of initial fuel mixture pressure under 60 kPa. The smaller facing step model resulted in reinitiation distant farther.At initial pressure 10 kPa with 25% facing step model the reinitiation detonation distance was 540 mm and hight pressure only reach 6 times of initial pressure meanwhilefor 75% facing step model it was 120 mm and peak pressure was 10 times of initial pressure. In cotralary the fuel initial effect was more dominating then facing step model variation in the pressure range more then 60 kPa.