Coil Heat Exchanger with the Nanofluid Filled Buffer Layer

Abstract:

The paper presents the preliminary design of the special heat exchanger. The device under consideration is the kind of immersed coil heat exchangers. It consists of three vertical coils: two coils are standard, water is used as a heating medium; one coil is filled by the refrigerant R134a which transfers the waste heat from refrigeration and air conditioning system during the boiling processes. In order to prevent the possible refrigerant leakage, the special buffer layer filled with the nanofluid is mounted in the Freon coil. Thermophysical properties of the nanofluid cause the intensification of the heat transfer through the buffer layer and the same increase of the heat transfer rate. Calculations of thermal power were made. Correlations of heat transfer coefficients in curved tubes, pressure drop correlations for flow through helical coil tubes and correlations describing the heat transfer in the buffer layer, were applied. Results of the calculations indicate of the influence of of Freon coil on the exchanger heat transfer rate. Heat power of Freon coil is about 7 – 25% of water coil thermal power. Thus, the waste heat applied significantly increases the exchanger heat transfer rate.

• Periodical: Applied Mechanics and Materials (Volume 831)
• Pages: 223-231
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.831.223
• Online since: April 2016
• Authors: Robert Smusz, Joanna Wilk*
• Keywords: Coil, Heat Exchanger, Nanofluid, Waste Heat

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