Set Of Thermal Coefficients Research Articles

A Novel Methodology for Combined Parameter and Function Estimation Problems

This article presents a novel methodology, which is highly efficient and simple to implement, for simultaneous retrieval of a complete set of thermal coefficients in combined parameter and function estimation problems. Moreover, the effect of correlated unknown variables on convergence performance is examined. The present methodology is a combination of two different classical methods: The conjugate gradient method with adjoint problem (CGMAP) and Box–Kanemasu method (BKM). The methodology uses the benefit of CGMAP in handling function estimation problems and BKM for parameter estimation problems. One of the unique features about the present method is that the correlation among the separate unknowns does not disrupt the convergence of the problem. Numerical experiments using measurement errors are performed to verify the efficiency of the proposed method in solving the combined parameter and function estimation problems. The results obtained by the present approach show that the combined procedure can efficiently and reliably estimate the values of the unknown thermal coefficients.

Phenomenological coefficients and frames of reference for transport processes in liquids and membranes. Part 2.—Resistance and conductance coefficients in non-isothermal systems

Phenomenological descriptions of transport processes in isotropic, non-reacting, non-isothermal systems are discussed in terms of thermal conductance and thermal resistance coefficients. It is shown that, for a non-viscous system containing n species, there is a set of 2n-1 independent thermal coefficients whether or not the system is at mechanical equilibrium. If the thermal coefficients are symmetric, then the number of independent coefficients is reduced to n. It is also shown that thermal resistance coefficients are related simply to heats of transfer, and both quantities are independent of the choice of reference velocity. If any set of thermal coefficients is symmetric, the symmetry of all other sets of thermal and isothermal coefficients is implied. The converse, however, is not necessarily true.