Publisher : The Korean Society of Mechanical Engineers
DOI : 10.3795/KSME-B.2016.40.2.103
Title & Authors
Measuring Apparatus for Convective Heat Transfer Coefficient of Nanofluids Using a Thermistor Temperature Sensor Lee, Shin Pyo;
Fine wires made from platinum have been used as sensors to evaluate the convection performance of nanofluids. However, the wire sensor is difficult to handle due to its fragility. Additionally, an unrealistic convective heat transfer coefficient (h) is obtained if a rigorous calibration process combined with precision equipment is not used for measurement. This paper proposes a new evaluation apparatus for h of nanofluids that uses a thermistor sensor instead of the platinum wire. The working principles are also explained in detail. Validation experiments for pure engine oil comparing h from the two sensors confirmed numerous practical benefits of the thermistor. The proposed system can be used as a useful tool to justify the adoption of developed nanofluids.
Nanofluids;Pure Fluid;Convective Heat Transfer Coefficient;Thermistor;Platinum Hot Wire;Positive/Negative Temperature Coefficient of Resistance;Cold Resistance;
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