Research based on double coverage rate and reliability of gas detector layout optimization. (November 2020)

• Record Type: Journal Article
• Authors: Cheng, Fangming; Zhang, Anbang; Wang, Tao; Chen, Yan; Chang, Zhuchuan; Ge, Tianjiao
• Is Part Of: Journal of loss prevention in the process industries. Volume 68(2020)
• Publication Date: 2020-11
• Subjects: Gas detector arrangement -- Fraction of coverage -- Reliability -- Voting mechanism -- FLACS -- Ray-casting algorithm; Chemical industries -- Safety measures -- Periodicals; 660.2804
• DOI: 10.1016/j.jlp.2020.104285
• Languages: English
• ISSNs: 0950-4230

Abstract

Abstract: The gas detector layout should be highly attuned to combustible gas leakage and attain a good reliability in avoiding detector malfunction, which is an important guarantee for the normal production of the chemical industry and other related enterprises. Herein, a gas detector layout optimization method based on double coverage and reliability is proposed. The key gas leakage monitoring area is determined through layout scene field investigation. To improve the detection probability and detection system reliability, the dual coverage target and voting mechanism are set, and the gas detector layout is determined with the ray-casting algorithm according to the coverage target. Combined with FLACS software to simulate a variety of typical leakage conditions under different layout scenarios, the relationship between the leaked gas concentration detected by gas detectors in each layout scheme and time is obtained, and the gas leakage detection probability in each layout scheme, number of detectors that can trigger the alarm, shortest time to trigger the alarm and reliability are comprehensively evaluated. The decision-maker selects the final gas detector layout plan according to the evaluation results and actual site needs. The study shows that the detection probability of each layout scheme set according to the double coverage is high, and multiple detectors can trigger the alarm (up to 100%), which ensures that the alarm can be triggered within 10 s under all applicable conditions. According to the evaluation results, the decision-maker can obtain a layout scheme that not only agrees with the actual site conditions but also attains a high detection probability, short detection time and strong reliability. Highlights: A gas detector layout method based on dual coverage and reliability is proposed. The reliability of detector system can be improved based on double coverage. Combined with CFD simulation, the layout is based on pertinence. According to the comprehensive analysis, the final layout can meet the actual needs.