Dear Researchers,
We are running a Special Issue titled " Challenges and Progresses in the Modelling of Entropy Generation in Fluid Mechanics, Heat Transfer and Porous Media " for Entropy (ISSN 1099-4300, IF 2.305).
Prof. Dr. M. M Rashidi ( University of Birmingam, UK) and
Dr. Munawwar Ali Abbas (University of Baltistan, Skardu, Pakistan) are serving as Guest Editors for this issue. We would like to invite you to contribute a review or full research paper for publication in this Special Issue after standard peer-review procedure in Open access form. You can see full details of the scope and submission details at the following web site:
https://www.mdpi.com/journal/entropy/special_issues/Entropy_Generation_FM_HT_PM
The so-called "entropy " doesn't exist at all.
During the process of deriving the so-called entropy, in fact, ΔQ/T can not be turned into dQ/T. That is, the so-called "entropy " doesn't exist at all.
The so-called entropy was such a concept that was derived by mistake in history.
It is well known that calculus has a definition,
any theory should follow the same principle of calculus; thermodynamics, of course, is no exception, for there's no other calculus at all, this is common sense.
Based on the definition of calculus, we know:
to the definite integral ∫T f(T)dQ, only when Q=F(T), ∫T f(T)dQ=∫T f(T)dF(T) is meaningful.
As long as Q is not a single-valued function of T, namely, Q=F( T, X, …), then,
∫T f(T)dQ=∫T f(T)dF(T, X, …) is meaningless.
1) Now, on the one hand, we all know that Q is not a single-valued function of T, this alone is enough to determine that the definite integral ∫T f(T)dQ=∫T 1/TdQ is meaningless.
2) On the other hand, In fact, Q=f(P, V, T), then
∫T 1/TdQ = ∫T 1/Tdf(T, V, P)= ∫T dF(T, V, P) is certainly meaningless. ( in ∫T , T is subscript ).
We know that dQ/T is used for the definite integral ∫T 1/TdQ, while ∫T 1/TdQ is meaningless, so, ΔQ/T can not be turned into dQ/T at all.
that is, the so-called "entropy " doesn't exist at all.
Here, there are some new contents that people didn't know before:
Heat Q (and work W ) is both a system Process Variable and a State Variable in the system process, this is a NEW class of Variables, to this class of process-related State Variables, we can call them Process State Variables (or Special State Variables), the loop integral of a Process State Variable is not 0.
In contrast, we can call the familiar state variable, such as internal energy, as the Ordinary State Variables, the loop integral of an Ordinary State Variables is always zero.
When the system goes from initial state 1 through a reversible loop to final state 2, the initial state 1 and the final state 2 coincide, to the system and the Ordinary State Variables(a.g., internal energy), the initial state 1 and the final state 2 are the same one state.
However, to the Process State Variables (such as heat Q and work W), the initial state 1 and the final state 2 are not the same state, but two different states, and the change of the function value of the Process State Variable are obtained by piecewise integration in general.
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