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Numerical Analysis of Convective Instabilities in a Transient Short-Hot-Wire Setup for Measurement of Liquid Thermal Conductivity

“…Finite size effects are however significant only for t b 2 /2κ [9], which, for b of the order of 1 cm, is typically for liquids in the hundreds of seconds range. One should also take into account that, since the wire resistance depends on temperature, the dissipated electrical power actually depends on time.…”

“…Therefore, the slope and intercept of the ∆T versus ln(t) curve can be used to simultaneously measure λ and κ. In practice, however, the experimental uncertainty for the thermal diffusivity is usually almost an order of magnitude larger than for the thermal conductivity [9]. A rigorous, albeit slightly more elaborated, analytical solution can still be obtained even assuming a finite thermal conductivity λ w and heat capacity (ρc p ) w of the wire [1]:…”

Characterization of a spherical heat source for measuring thermal conductivity and water content of ethanol and water mixtures

“…The standard test method for the determination of thermal conductivity of nonmetallic liquids of the American Society for Testing and Materials (ASTM) is based on this method [2]. An extensive uncertainty assessment elaborated for the hot-wire method obtained the value of 5.8% for the thermal conductivity [3], although other literatures claim for uncertainty values better than 5%.…”

A Steady-State Apparatus to Measure the Thermal Conductivity of Solids

“…The thermal conductivity and thermal diffusivity of the sample may be directly derived from the temperature rise of the wire or the strip. The typical standard uncertainty (k = 1) of a THS apparatus assessed against the reference material CRM 039 (Pyrex glass) is ±2.5% for the thermal conductivity and ±11% for the thermal diffusivity [1], whereas the typical standard uncertainty (k = 1) of a THW apparatus against the same reference material is ±2.9% and ±15%, respectively [2].…”