|Journal||Journal of Mechanical Engineering|
|Publisher||A. Pidhornyi Institute for Mechanical Engineering Problems
National Academy of Science of Ukraine
|ISSN||2709-2984 (Print), 2709-2992 (Online)|
|Issue||Vol. 23, no. 4, 2020 (December)|
|Cited by||J. of Mech. Eng., 2020, vol. 23, no. 4, pp. 14-21|
When creating ventilation systems, it is important to correctly calculate the volumes of air inflow and outflow. If an error is made in the calculation or a redistribution of air flows is required, measurements are indispensable. The existing methods for determining the air flow rate by using point measurements in the cross-section are laborious and time-consuming, and taking readings at different time points introduces a significant error into the result. A. M. Pidhornyi Institute of Mechanical Engineering Problems of the National Academy of Sciences of Ukraine has developed a new hot-wire anemometer whose use greatly simplifies the measuring process. This device allows one to measure the average values of temperature and air velocity (flow rate) in the cross-section of air ducts or at the inlets and outlets of grilles and anemostats, and can be used in real time to monitor and control air flow rate and temperature in ventilation systems. The probe of the hot-wire anemometer is a metal shell with guides on which a sensitive element is laid. Its principle of operation is to change the heat transfer coefficient at different air leakage velocities. The anemometer is preliminarily calibrated in laboratory conditions at various velocities. There has been obtained a calibration dependence that can be used to measure the air flow rate at the inlets and outlets of air distribution devices and directly in the air ducts. To improve the measurement accuracy, it is necessary to provide the 90° angle of airflow leakage on the hot-wire anemometer probe. For this, special air collectors and air flow rectifiers are used.
Keywords: hot-wire anemometer, measurements, sensitive element.
Full text: Download in PDF
- O’Sullivan, J., Ferrua, M., Love, R., Verboven, P., Nicolaï, B., & East, A. (2014). Airflow measurement techniques for the improvement of forced-air cooling, refrigeration and drying operations. Journal of Food Engineering, vol. 143, pp. 90–101. https://doi.org/10.1016/j.jfoodeng.2014.06.041.
- Ower, E. & Pankhurst, R. C. (2014). The Measurement of Air Flow. United Kingdom, Oxford: Pergamon, 384 p.
- Ikeya, Y., Örlü, R., Fukagata, K., Alfredsson, P. H. (2017). Towards a theoretical model of heat transfer for hot-wire anemometry close to solid walls. International Journal of Heat and Fluid Flow, vol. 68, pp. 248–256. https://doi.org/10.1016/j.ijheatfluidflow.2017.09.002.
- Saremi, S., Alyari, A., Feili, D., & Seidel, H. (2014). A MEMS-based hot-film thermal anemometer with wide dynamic measurement range. Proceedings IEEE Conferences on Sensors (SENSORS’2014). Valencia, Spain, 2–5 November 2014, pp. 420–423. https://doi.org/10.1109/ICSENS.2014.6985024.
- Burgess, W. A., Ellenbecker, M. J., & Treitman, R. D. (2004). Airflow measurement techniques. Ventilation for control of the work Environment. USA, New Jersey, Hoboken: Wiley-Interscience, 440 p. https://doi.org/10.1002/0471667056.ch3.
- Manshadi, M. D. & Esfeh, M. K. (2012). A new approach about heat transfer of hot-wire anemometer. Applied Mechanics and Materials, vol. 232, pp. 747–751. https://doi.org/10.4028/www.scientific.net/AMM.232.747.
- Örlü, R. & Vinuesa, R. (2017). Thermal anemometry. In: Discetti S., Ianiro A. (eds.) Experimental Aerodynamics. USA, Florida: CRC Press, pp. 257–304. https://doi.org/10.1201/9781315371733-12.
- Taratyrkin, K. Ye. & Chernoivanov, D. V. (2017). Otsenka tochnosti opredeleniya raskhoda vozdukha v sistemakh ventilyatsii pri ikh pasportizatsii [Evaluation of the accuracy of determining the air flow rate in ventilation systems during their certification]. Ventilyatsiya, otopleniye, konditsionirovaniye vozdukha, teplosnabzheniye i stroitelnaya teplofizika – Ventilation, Heating, Air Conditioning, Heat Supply and Building Thermal Physics, no. 3, pp. 54–59 (in Russian).
- Care, I. & Arenas, M. (2015). On the impact of anemometer size on the velocity field in a closed wind tunnel. Flow Measurement and Instrumentation, vol. 44, pp. 2–10. https://doi.org/10.1016/j.flowmeasinst.2014.11.007.
- Foss, J. F., Peabody, J. A., Norconk, M. J., & Lawrenz, A. R. (2006). Ambient temperature and free stream turbulence effects on the thermal transient anemometer. Measurement Science and Technology, vol. 17, no. 9, pp. 2519–2526. https://doi.org/10.1088/0957-0233/17/9/020.
- Tsakanyan, O. S. & Koshel, S. V. (2005). Issledovaniye teplootdachi i aerodinamicheskogo soprotivleniya provolochnykh konstruktsiy teploobmennykh poverkhnostey. Chast 1. Spiralnyye i reshetchatyye poverkhnosti teploobmena [Research of heat transfer and aerodynamic resistance of wire structures of heat exchange surfaces. Part 1. Spiral and lattice heat transfer surfaces]. Problemy mashinostroyeniya – Journal of Mechanical Engineering, vol. 8, no. 3, pp. 22–29 (in Russian).
- Tsakanyan, O. S. & Koshel, S. V. (2008). Teploobmen spiralno-toroidalnykh poverkhnostey pri peremennykh uglakh ataki potoka [Heat transfer of spiral-toroidal surfaces at variable angles of attack of the flow]. Problemy mashinostroyeniya – Journal of Mechanical Engineering, vol. 11, no. 2, pp. 24–31 (in Russian).
Received 07 May 2020
Published 30 December 2020