When designing a local ventilation system, insufficient attention is often paid to the process of the extraction hood optimization. The main reason for this is the lack of research and knowledge in this field. However, by developing a suitable hood for a given application, the capture efficiency and/or the overall energy efficiency of the system could be significantly improved. Considering these findings, we conducted an experiment with the aim of gaining new knowledge about the impact of hood shape on airflow. To conduct the experiment, we first designed and manufactured four different hoods, then installed them on the test track in the company's measurement laboratory. Using a hot film anemometer, we then executed point measurements of air velocity under the hoods on a symmetrical plane of the cross-section of the hood.The measured values were then analysed and presented in a form suitable for identification of the airflow characteristics. Patterns were then mutually compared and the variations were discussed, afterwards we formulated recommendations for future projects in regard to the acquired knowledge.
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