Thermal conductivity measurement of liquids in a microfluidic device

Kuvshinov, D.; Bown, M. R.; MacInnes, J. M.; Allen, R. W.K.; Ge, R.; Aldous, L.; Hardacre, C.; Doy, N.; Newton, M. I.; McHale, G.

Abstract

A new microfluidic-based approach to measuring liquid thermal conductivity is developed to address the requirement in many practical applications for measurements using small (microlitre) sample size and integration into a compact device. The approach also gives the possibility of high-throughput testing. A resistance heater and temperature sensor are incorporated into a glass microfluidic chip to allow transmission and detection of a planar thermal wave crossing a thin layer of the sample. The device is designed so that heat transfer is locally one-dimensional during a short initial time period. This allows the detected temperature transient to be separated into two distinct components: a short-time, purely one-dimensional part from which sample thermal conductivity can be determined and a remaining long-time part containing the effects of three-dimensionality and of the finite size of surrounding thermal reservoirs. Identification of the one-dimensional component yields a steady temperature difference from which sample thermal conductivity can be determined. Calibration is required to give correct representation of changing heater resistance, system layer thicknesses and solid material thermal conductivities with temperature. In this preliminary study, methanol/water mixtures are measured at atmospheric pressure over the temperature range 30-50°C. The results show that the device has produced a measurement accuracy of within 2.5% over the range of thermal conductivity and temperature of the tests. A relation between measurement uncertainty and the geometric and thermal properties of the system is derived and this is used to identify ways that error could be further reduced. © 2010 Springer-Verlag.

Citation

Kuvshinov, D., Bown, M. R., MacInnes, J. M., Allen, R. W., Ge, R., Aldous, L., Hardacre, C., Doy, N., Newton, M. I., & McHale, G. (2011). Thermal conductivity measurement of liquids in a microfluidic device. Microfluidics and Nanofluidics, 10(1), 123-132. https://doi.org/10.1007/s10404-010-0652-x

• Journal Article Type: Article
• Acceptance Date: May 27, 2010
• Online Publication Date: Jun 10, 2010
• Publication Date: Jan 1, 2011
• Deposit Date: Apr 21, 2022
• Journal: Microfluidics and Nanofluidics
• Print ISSN: 1613-4982
• Publisher: Springer Verlag
• Peer Reviewed: Peer Reviewed
• Volume: 10
• Issue: 1
• Pages: 123-132
• DOI: https://doi.org/10.1007/s10404-010-0652-x
• Keywords: Liquid thermal conductivity measurement; Resistance temperature sensor; Microfluidic device; Small sample volume
• Public URL: https://hull-repository.worktribe.com/output/3591673