@article{ajme2020832,
author={Adiutori, Eugene F.},
title={Why Heat Transfer Coefficients Are Unnecessary and Undesirable, and How Heat Transfer Problems Are Solved without Them},
journal={American Journal of Mechanical Engineering},
volume={8},
number={3},
pages={106--110},
year={2020},
url={http://pubs.sciepub.com/ajme/8/3/2},
issn={2328-4110},
abstract={For 200 years, convective heat flux *q* has been calculated by multiplying heat transfer coefficient *h* times boundary layer temperature difference Δ*T*. Since *h *times Δ*T *equals *q, h must* be a symbol for* (q/*Δ*T)* because *(q/*Δ*T) *times* *Δ*T* equals *q.* *h* (ie *q/*Δ*T*) is generally calculated from correlations derived from experiments in which *q* data and Δ*T* data are used to obtain *(q/*Δ*T){*Δ*T}* correlations-ie *h{*Δ*T}* correlations. (It is not possible to obtain *h* data because *h* is not a parameter. *h* is the ratio of *two *parameters). Heat transfer coefficients are *unnecessary* and *undesirable*. It is self-evident that any problem that can be solved using *q, q/*Δ*T (ie h)*, and Δ*T* can also be solved using only *q* and Δ*T*. Therefore *h* (ie *q/*Δ*T*) is *unnecessary.* *h* (ie *q/*Δ*T*) is *undesirable* because, when *q* is a nonlinear function of Δ*T* (as in free convection, condensation, and boiling), *h* (ie *q/*Δ*T*) is an extraneous *variable*, and it *greatly* complicates problem solutions. When *h* has been abandoned, convective heat flux is determined from *q{*Δ*T}* correlations that result from *q* data and Δ*T* data, or from the transformation of *h{*Δ*T}* correlations. (Transformation from *h{*Δ*T}* correlations to *q{*Δ*T}* correlations requires that *h* be replaced by *q/*Δ*T*, and that *q* and Δ*T* be separated.). The text includes example problems that validate the conclusion that *h* (ie *q/*Δ*T*) is unnecessary and undesirable, and demonstrate that the solution of nonlinear problems is much simpler if *h* is abandoned.},
doi={10.12691/ajme-8-3-2}
publisher={Science and Education Publishing}
}