Real-time prediction of calorimeter equilibrium

Abstract

Calorimetry is an accurate means for nondestructive quantitative analysis of heat-generating materials, but the time required for attainment of thermal equilibrium within the calorimeter has often limited its use in production applications. A means of predicting calorimeter equilibrium values mathematically is presented which reduces analysis times by an average of 55%, thereby enhancing the usefulness of the method. The prediction of calorimeter equilibrium makes use of the fact that the calorimeter thermal response function is dominated by a single, time-dependent exponential. Monitoring the output of the calorimeter at equally spaced time intervals allows the equilibrium value to be predicted in advance of an actual equilibrium condition with accuracy in the bounds of the 95% confidence level. A time factor improvement factor average of 2.25 over conventional calorimetry practice was realized without instrument modifications.