Abstract

About Part one

Editorial Board of the journal Thermal Science consistently follows the policy to prepare issues devoted to the specific, modern scientific topics. Having eminent guest editors, and thanks to their agility and efforts we had in the past several years a number of excellent special issues devoted to a wide scope of topics.
This time, our most active Guest editor Prof. Jordan Hristov, proposed an extremely interesting topic – Fractional calculus to Heat, Momentum and Mass Transfer Problems.
Last year we had also an excellent special issue devoted to analytical methods in thermal sciences, with a nice set of papers chosen by Prof. Ji-Huan He. Present selection of eleven papers devoted to fractal calculus made by Prof. Hristov in
Part I, No. 2, 2012, gives nice insight into the capabilities of this scientific tool in solving problems in heat, mass, and momentum transfer. This can be clearly seen not only by reading papers
in Part I of this issue, but also from the nice preface written by Prof. Hristov. I amdeeply grateful to the Guest editor, Prof. Jordan Hristov (Department of Chemical Engineering, University of Chemical Technology and Metallurgy, Sofia, Bulgaria), not only for proposing this topic and for excellent paper selection, but also for permanent care to improve the journal Thermal Science, and to ensure that topics of the published paper are of the current scientific interest. The journal Thermal Science will try, in the future issues also, to make a balance between numerical and analytical methods for modeling processes in thermal sciences, in order to present to the readers a wide scope of possible approaches.

About Part two
Research of the processes in nanofluids (flow, heat and mass transfer, chemical processes…) is a modern topic to which Thermal Science wants to pay special attention. This is the reason why in Part two of this issue we make an ad hoc collection of six papers presently accepted for publication and devoted to this topic. We believe that this collection of papers will be interesting for readers carrying out research in this field, and also to other researchers who want to be informed about this modern topic. Also, we want to induce researchers to submit to our journal more papers dealing with nanofluids.

About Part three
Last 11 papers are devoted to different, more applied problems and processes present in modern energy technologies and use of renewable energy sources. In Open Forum potential of the fractal calculus to solve transient heat conduction problems is demonstrated and discussed. Important note – On-line paper submission Number of papers submitted for publication in the journal Thermal Science has been growing extremely fast in the last several years. In order to facilitate editing of the journal, reviewing process, and process of paper submission, and following history of the papers, Editorial Board of the journal Thermal Science undertook an action to introduce electronic system for journal editing, and more importantly for authors an on-line paper submission process thorough our web site. We believe that this system will be in operation starting from the beginning of the 2013. Prof. Dr. Simeon Oka