Precision Measurements of Thermal Conductivity: Extending the Ability of a Commercial Instrument
Major
Physics
Submission Type
Poster
Area of Study or Work
Chemistry, Mathematics, Physics
Faculty Advisor
Narendra Jaggi
Location
CNS Atrium
Start Date
4-11-2026 8:30 AM
End Date
4-11-2026 9:45 AM
Abstract
Accurate measurement of thermal conductivity is essential across materials science, engineering, and energy research. The TEMPOS Thermal Property Analyzer is among the leading commercial instruments for this purpose, reporting thermal conductivities with an accuracy of approximately ±10% over a range of 0.1–4.0 W·m⁻¹·K⁻¹. While this performance is sufficient for many applications, the following central question motivates our project: what ultimately limits the accuracy of this instrument, or others like it? Our work begins by clearly articulating the underlying measurement principle of the TEMPOS system, which is based on the transient line heat source method. In this approach, a controlled heat pulse is introduced into a material, and the resulting temperature rise over time is analyzed to determine thermal conductivity using a heat diffusion equation for a cylinder. We try to identify possible sources of uncertainty through both careful study of the relevant literature and direct experimental investigation. These sources may include probe calibration, thermal contact resistance between probe and sample, assumptions built into the mathematical model, ambient temperature fluctuations, electronic noise, and data-processing limitations. To move beyond black-box characterization, we will examine the internal structure of the commercial instrument in order to better understand its sensing architecture, electronics, and signal processing pipeline. We will also attempt to design and construct an open prototype instrument in which individual components—heater geometry, temperature sensing elements, timing control, and data acquisition—can be independently tested and adjusted. By comparing measurements from the commercial device and our prototype system, we aim to clarify which factors most strongly constrain accuracy and to explore whether meaningful improvements in precision are achievable.
Precision Measurements of Thermal Conductivity: Extending the Ability of a Commercial Instrument
CNS Atrium
Accurate measurement of thermal conductivity is essential across materials science, engineering, and energy research. The TEMPOS Thermal Property Analyzer is among the leading commercial instruments for this purpose, reporting thermal conductivities with an accuracy of approximately ±10% over a range of 0.1–4.0 W·m⁻¹·K⁻¹. While this performance is sufficient for many applications, the following central question motivates our project: what ultimately limits the accuracy of this instrument, or others like it? Our work begins by clearly articulating the underlying measurement principle of the TEMPOS system, which is based on the transient line heat source method. In this approach, a controlled heat pulse is introduced into a material, and the resulting temperature rise over time is analyzed to determine thermal conductivity using a heat diffusion equation for a cylinder. We try to identify possible sources of uncertainty through both careful study of the relevant literature and direct experimental investigation. These sources may include probe calibration, thermal contact resistance between probe and sample, assumptions built into the mathematical model, ambient temperature fluctuations, electronic noise, and data-processing limitations. To move beyond black-box characterization, we will examine the internal structure of the commercial instrument in order to better understand its sensing architecture, electronics, and signal processing pipeline. We will also attempt to design and construct an open prototype instrument in which individual components—heater geometry, temperature sensing elements, timing control, and data acquisition—can be independently tested and adjusted. By comparing measurements from the commercial device and our prototype system, we aim to clarify which factors most strongly constrain accuracy and to explore whether meaningful improvements in precision are achievable.