كاربرد امواج آكوستيك در شناسايي مقدار و مكان گازهاي خروجي در لوله انتقال گاز

APPLICATION OF ACOUSTIC WAVES IN DETECTION OF THE LEAKAGE POSITION AND FLOW RATE IN A GAS

In this paper , a leak detection method , based on an acousti c approach, is presented for tubular systems. An energy balance meth odology for acoustic waves is proposed as a means to detect both the possible occurrence of a leak , as well as an est imation of its position and leakage flow rate. Information on the incident, transmitted, absorbed , reflected acoustic energy and wave amplitude will enable one to determine the leakage position , as well as its flow rate. Th e presence of a leak will result in a change of the wall impedance. Th e govern ingequa tions are derived and a finite differen ce scheme is used to solve them. Results are presented for variations of the aconstic energy for tran smission , a bsorption and reflection with leak size and wave frequency. The effects of different leak sizes and pinhole positions on the propagation of an acoustic pressure wave are studied.