THW-01LNG

THW-01LNG

THW-01LNG

The Transient Hot-Wire technique has successfully been applied for the measurement of the thermal conductivity of fluids since 1980

Description

The THW-01LNG Method

According to the transient hot-wire technique, the thermal conductivity of the sample is determined by observing the temporal temperature rise of a thin wire, when a step voltage is applied to it. In this way, electrical current flows through the wire and heats it up, thus creating in the liquid a line source of essentially uniform heat flux per unit length that depends on the thermal conductivity of the liquid. Finally, to avoid end effects, two wires identical except for their length, are employed. Thus, if arrangements are made to measure the difference of the resistance of the two wires as a function of time, the measurement corresponds to the resistance change of a finite section of an infinite wire (as the end effects being very similar, are subtracted), from which the temperature rise can be determined. This way absolute measurements can be performed (i.e. no calibration or reference sample is required).

An automatic electronic bridge records 500 resistance rise points in time from 0.01 to 1 s. These are converted to temperature rise vs time. Once small correction has been applied (because if the heat capacity of the wire, the variable fluid properties, and the outer boundary of the cell), the thermal conductivity is obtained from the slope of the temperature rise vs time.

THW-01LNG advantages

• Digital
• Benchtop
• Highest Accuracy
• Automatic
• Rapid and reliable results
• Ease of use

Applications and Market sectors

• Liquids
• Nanofluids
• Gases
• Natural gas mixtures
• Beverages
• Pharmaceutical fluids
• Oils
• EVs fluids

Specifications