Visualization and Measurement of Boiling Flow Behaviors in Parallel Mini-channel Heat Exchanger by Neutron Radiography
Hitoshi Asano, Hideki Murakawa, Ryosuke Moriyasu, Katsumi Sugimoto, Yohei Kubo, Kazuhisa Fukutani, Daisuke Ito, Yasushi Saitodownload PDF
Abstract. Boiling two-phase flows in cross-flow type mini-channel evaporator were visualized by neutron radiography. Refrigerant vertically upward flow of HFC134a [CH2FCF3] in 21 parallel channels with the hydraulic diameter of 1.47 mm was heated by the heating medium of fluorocarbon FC3283. Void fraction distributions of evaporating two-phase flows were measured by neutron radiography. The effect of the inlet orifices for each refrigerant channel to prevent flow instability was evaluated. The refrigerant was supplied to the test section as subcooled liquid with the mass flux of 50 to 100 kg/(m2s). The heating medium was supplied with the mass flux of 460 and 920 kg/(m2s) and at the inlet temperature of 47.1 to 67.2 °C. As the result, it is shown that void fraction close to the inlet of heating medium was relatively higher. Flow instability of boiling flows and the effect of the inlet orifices were not observed.
Compact Heat Exchanger, Parallel Channel, Evaporator, Void Fraction, HFC134a, Neutron Radiography
Published online 1/5/2020, 7 pages
Copyright © 2020 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Hitoshi Asano, Hideki Murakawa, Ryosuke Moriyasu, Katsumi Sugimoto, Yohei Kubo, Kazuhisa Fukutani, Daisuke Ito, Yasushi Saito, Visualization and Measurement of Boiling Flow Behaviors in Parallel Mini-channel Heat Exchanger by Neutron Radiography, Materials Research Proceedings, Vol. 15, pp 274-280, 2020
The article was published as article 43 of the book Neutron Radiography
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