Inventors:
Norman Gershfeld - Bethesda MD
Courtney Mudd - Great Falls VA
Albert Jin - Silver Springs MD
Kazuhiro Fukada - Tokyo, JP
Assignee:
The United States of America as respresented by the Department of Health
and Human Services - Washington DC
International Classification:
G01N 2518
G01N 2500
Abstract:
A method of simultaneously measuring thermal conductivity and heat capacity of a fluid, using a heat conduction calorimeter having a reference fluid in a first cell and a sample fluid in a second cell includes the steps of calibrating the calorimeter using a standard fluid having known thermal conductivity and heat capacity over a range of temperatures and the reference fluid to determine a set of sensitivity parameters, {a. sub. n. sup. ij }, of the calorimeter, wherein the a. sub. n. sup. ij are functions of the calorimeter, temperature and the reference fluid; applying a square wave heat pulse to the calorimeter containing said sample fluid and said reference fluid; measuring the thermal response curve to the square wave heat pulse, wherein the thermal response curve is a function of time, temperature of the measurement, thermal properties of the sample fluid, and thermal properties of the reference fluid; reducing the response curve to a set of discrete characteristic parameters, {p. sub. n } wherein each pn is a function of time, temperature of the measurement, thermal properties of the sample fluid and thermal properties of the reference fluid; calculating the thermal conductivity and heat capacity of the sample fluid from the {p. sub. n } for the sample fluid and the {a. sub. n. sup.