Method and device for measuring the thermal conductivity of a multifunctional fluid

A device for continuous measurement of thermal conductivity of a multi-functional fluid, the device comprising;

• a means designed to pass a sample of the multi-functional fluid through a space delimited by a first input face and a second exit face of the sample;
• a means for heating the sample to vary a temperature of the sample,
• a means to measure variation of the temperature of the sample
• a means to transmit to the sample, at least a very brief impulse of heat flux, through the first input face,
• a means to measure a heat wave at three or more separate points within the sample;
• a means to determine, on a basis of values measured, a temperature evolution of the multi-functional fluid as a function of time at the separate points within the sample;
• a means to deduce, from the temperature evolution, thermodynamic characteristics of the sample of the multi-functional fluid;
• and
• a means to calculate thermal conductivity of this sample, and;
• wherein the means to determine the temperature evolution of the multi-functional fluid as a function of time comprises at least three temperature probes (S1, S2, S3) designed to measure the temperature of the sample of the multi-functional fluid at the at least three separated points within the sample.

A method for continuous measurement of thermal conductivity of a multi-functional fluid, the method comprising the steps of:

• passing a sample of the multi-functional fluid through a space delimited by a first input face and a second exit face;
• generating an increase in temperature of the sample of multi-functional fluid, at least by a very brief impulse of heat flux transmitted to the sample, through the first input face;
• measuring the temperature increase with at least three temperature probes within the sample;
• determining with the temperature increase measurement, an evolution of the multi-functional fluid temperature at the three temperature probes as a function of time;
• determining thermodynamic characteristics of the sample of the multi-functional fluid as a function of the evolution;
• and
• calculating a thermal conductivity of the sample.