Study on the Characteristics of Harmful Gas Distribution of Welding Semi-Closed Environment

Abstract:

In order to reveal the harmful gas distribution characteristics of welding semi-closed field, this paper established a welding workshop model. Under conditions of natural and mixed convection, the flow state of CO generated in the welding process within the workshop was simulated based on the zero-equation turbulence model. The distribution of CO was analyzed under the conditions of different exhaust rate and different number of working welder. Studies have shown that higher concentration CO appears in the region of 0.6m to 1.5m from the ground; it is necessary to adjust the number of air vents when the number of welder is changing. In addition, the asymmetric structure of workshop also affects the distribution of CO. The simulation results not only can evaluate the pros and cons of the workshop structure and ventilation system, but also provide a theoretical basis for hazardous gas detection and alarm strategy for the further purposes.

• Periodical: Applied Mechanics and Materials (Volumes 316-317)
• Pages: 441-445
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.316-317.441
• Online since: April 2013
• Authors: Shun Shun Qi, Shu Jin Chen, Sen Hu, Wen Qi Zhu
• Keywords: Harmful Gas, Numerical Simulation, Welding Closed Field

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