• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.2
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• pp.186-191
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• 2006

In this study, five experiments were carried out, with an orifice located downstream of a fan in case I where upstream duct length is 6 D, and that in the downstream is 4 D and different downstream distance to the fan in the rest, so as to determine the optimal location of the orifice and reduce the duct length of airflow measurement device. The resulting flow rate-pressure drop correlations were found to satisfy the limitation of SMACNA standard, which specified an error of $\pm7.5\%$ based on the real flow rate. Also, the best one of five. cases was achieved with the orifice located midway of the orifice duct four times its diameter long.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.2151-2156
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• 2004

In this study, five experiments were carried out, with an orifice located downstream of a fan in case I and upstream distance to the fan in the rest cases(case $II{\sim}$), so as to determine the optimal location of the orifice and reduce the size of airflow measurement device. The resulting flow rate-pressure drop correlations were found to satisfy the limitation of SMACNA standard, which specified an error of ${\pm}7.5%$ based on the real flow rate. The best outcome was achieved with the orifice located midway of the orifice duct 4 times its diameter long.

• Fire Science and Engineering
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• v.31 no.1
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• pp.1-9
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• 2017

This study conducted Testing, Adjusting, and Balancing (TAB), which is a type of field performance evaluation experiment of a zone smoke-control system, at a railway underground transit passage installed with a zone smoke- control system to find problems and improvements for ensuring performance. TAB for the smoke control system was classified into several procedures, such as design data review, duct leakage test, field measurement of the airflow rate, velocity of the fan and duct, and a smoke test. Through the duct leakage test, the system leakage ratio was examined to prove the duct sealing. The iImprovement of the smoke control airflow problems due to the lack of fan static pressure loss was the secured performance. The performance of the smoke control fan was secured by improvements of the smoke control airflow rate problems caused by the loss of static pressure in the intake duct. The smoke test in the smoke control zone confirmed that the damper operating schedule subject was influenced by natural wind or train wind.