Research on variable air volume control systems of laboratory fume hoods based on performance test

 In this paper, the performance of the three most commonly used variable air volume (VAV) control methods for fume hoods, such as face velocity control, response time, steady time and tracer gas containment, is studied through test methods, and the test data is compared and analysed. The results show that the three different control methods can effectively control the face velocity of the fume hood, but there are obvious differences in response time, steady time and tracer gas containment. The comprehensive performance of the VAV control system with the combination of the displacement sensor and Venturi valve is better than that of the VAV control system with the combination of the displacement sensor and Venturi butterfly damper, and the leakage concentration of pollutants in the hood is lower. The VAV control system with the combination of face velocity sensor and butterfly damper has the longest response time and steady time, and the highest risk of pollutant leakage in the hood.