35th UIT (Italian Union of Thermo-fluid dynamics) Heat Transfer Conference – Ancona (Italy) 26-28 June 2017PrefaceThe 35th UIT (Italian Union of Thermp-Fluid Dynamics) Heat Transfer Conference was organized by Dept. of Industrial Engineering and Mathematical Sciences, Marche Polytechnic University (Itay) and was held at Faculty of Engineering of the same University, Ancona, June 26-28, 2017.The annual UIT Conference, which has grown over time, comes back in Ancona after 27 years.The scope of the conference covers a range of major topics in theoretical, numerical and experimental heat transfer and related areas, ranging from energy efficiency to nuclear plants. The Organizing Committee was also honored to continue the initiative about the new section devoted to Technical Seminars introduced 2015 within UIT conferences. In particular a seminar regarding the adoption of Unmanned Aerial Vehicles for Thermo-Fluid Dynamics research was held. Moreover a photo exhibition supported by “Aeronanutica Militare Italiana” was also offered to the participants.In this conference edition, 73 papers were contributed by about 300 authors on eight different topics: micro and nano scale thermo-fluid dynamics; multi-phase fluid dynamics, heat transfer and interface phenomena; computational fluid dynamics and heat transfer; heat transfer in nuclear plants; heat transfer and efficiency in energy systems, environmental technologies and buildings; natural, forced and mixed convection; conduction; heat transfer in fire engineering.The conference program scheduled plenary, oral and poster sessions. The two invited plenary Keynote Lectures were given by Prof. Giovanni Latini (Marche Polytechnic University, Italy) and Prof. Peter Stephan (Technische Universitat Darmstadt, Germany). A Technical Seminar was given by Prof. Renato Ricci (Marche Polytechnic University, Italy). There were also 9 oral sessions and a poster sessions.This special issue collects a paper presented in a keynote lecture plus 56 papers selected from those presented and discussed during the congress.The UIT 2017 conference was a useful occasion to stimulate discussion, further the understanding of heat transfer and related phenomena, present the state-of-the-art of some topics, discuss emerging trends and promote collaborations. We hope this issue will maintain and extend some of these features.A special thank you is due to the Organizing and Scientific Committees, to the sponsors and to all the participants.Renato Ricci and Valerio D’Alessandro, editors.List of Scientific Committee, Organizing Committee, UIT Sterring Committee, UIT Accounting Auditors, UIT Conferences are available in this pdf.