**Subscripts or superscripts**

operating conditions. These correlations have uncertainties of about �25% for HTC values and about �15% for calculated wall temperature. Also, based on an independent study performed by Zahlan et al. [55, 56], Pioro-Mokry correlation (given as Eq. (2)) is the best for superheated steam compared to other well-known correlations. Also, this

The author would like to express his appreciation to his former and current students, S. Clark, A. Dragunov, S. Gupta, M. Mahdi, D. Mann, S. Mokry, R. Popov,

G. Richards, Eu. Saltanov, H. Sidawi, E. Tamimi, and A. Zvorykin, for their assistance in the preparation of figures and developing of correlations.

*cp* specific heat at constant pressure, J/kg K *cp* averaged specific heat within the range of

(*Tw* – *Tb*); *Hw*�*Hb*

*Tw*�*Tb* 

, J/kg K

K

s; *<sup>m</sup> Afl* 

; *<sup>Q</sup> Ah* 

> 2

> > /s; *<sup>k</sup> cp*� *ρ*

/s; *<sup>μ</sup> ρ* 

> *α*

*k* 

*k* <sup>¼</sup> *<sup>υ</sup>*

/s

/kg

correlation showed quite good predictions for subcritical-pressure fluids.

**Acknowledgements**

*Advanced Supercritical Fluids Technologies*

**Nomenclature**

**Greek letters**

**34**

*A* area, m<sup>2</sup>

*D* inside diameter, m *G* mass flux, kg/m<sup>2</sup>

*L* heated length, m

*Q* heat transfer rate, W *q* heat flux, W/m<sup>2</sup>

*s* specific entropy, J/kg K *T, t* temperature, °C

*V* volume-flow rate, m<sup>3</sup>

*v* specific volume, m<sup>3</sup>

*x* axial coordinate, m

*Δ* difference *η* efficiency, %

**Non-dimensional numbers**

*ρ* density, kg/m<sup>3</sup>

*<sup>α</sup>* thermal diffusivity, m<sup>2</sup>

*μ* dynamic viscosity, Pa�s

*<sup>υ</sup>* kinematic viscosity, m<sup>2</sup>

**Nu** Nusselt number; *<sup>h</sup>* �*<sup>D</sup>*

**Pr** Prandtl number; *<sup>μ</sup>* �*cp*

*β* volumetric expansion coefficient, 1/K

*T*film film temperature, °C; *<sup>T</sup>*wþ*T*<sup>b</sup>

*P, p* pressure, Pa

*H* specific enthalpy, J/kg

*h* heat transfer coefficient, W/m<sup>2</sup>

*k* thermal conductivity, W/m K

*m* mass-flow rate, kg/s; ð Þ *ρ* � *V*


### **Abbreviations and acronyms**



**References**

2000. pp. 1-29

USA, April; 1946

[1] Levelt Sengers JMHL. Supercritical fluids: Their properties and applications, Chapter 1. In: Kiran E et al., editors. Supercritical Fluids. Vol. 366.

*DOI: http://dx.doi.org/10.5772/intechopen.91474*

Generation III and III<sup>+</sup> nuclear power plants. ASME Journal of Nuclear Engineering and Radiation Science.

[8] Pioro I, Kirillov P. Current status of electricity generation at thermal power plants. In: Méndez-Vilas A, editor. Materials and Processes for Energy: Communicating Current Research and Technological Developments, Energy Book Series #1. Spain: Formatex research Center; 2013. pp. 796-805. Available from: http://www.formatex. info/energymaterialsbook/book/

[9] Pioro IL, Duffey RB. Heat Transfer

and Hydraulic Resistance at Supercritical Pressures in Power Engineering Applications. New York, NY, USA: ASME Press; 2007. p. 328

[10] IAEA-TECDOC-1900, 2020. Understanding and Prediction of Thermohydraulic Phenomena Relevant to Supercritical Water Cooled Reactors (SCWRs), Final Report of a Coordinated Research Project, IAEA TECDOC Series,

Vienna, Austria, 544 pages. Free download from: https://www.iaea.org/ publications/13636/understanding-and-

prediction-of-thermohydraulicphenomena-relevant-to-supercritical-

[11] Oka Y, Koshizuka S, Ishiwatari Y, Yamaji A. Super Light Water Reactors and Super Fast Reactors. New York, NY,

[13] Schulenberg T, Starflinger J, editors. High performance light water reactor.

water-cooled-reactors-scwrs

USA: Springer; 2010. p. 416

[12] Pioro I. The potential use of supercritical water-cooling in nuclear reactors. In: Krivit SB, Lehr JH, Kingery TB, editors. Nuclear Energy Encyclopedia: Science, Technology, and Applications. Hoboken, NJ, USA: J. Wiley & Sons; 2011. pp. 309-347

2015;**1**(2):10

*Supercritical-Fluids Thermophysical Properties and Heat Transfer in Power-Engineering…*

796-805.pdf

Netherlands: NATO Advanced Study Institute on Supercritical Fluids— Fundamentals and Application, NATO Science Series, Series E, Applied Sciences, Kluwer Academic Publishers;

[2] Schmidt E, Eckert E, Grigull V. Heat transfer by liquids near the critical state. AFF Translation, No. 527, Air Materials Command, Wright Field, Dayton, OH,

[3] Pioro LS, Pioro IL. Industrial Two-Phase Thermosyphons. New York, NY, USA: Begell House, Inc.; 1997. 288 pp

[4] Pioro I, Duffey RB, Kirillov PL, Pioro R, Zvorykin A, Machrafi R. Current status and future developments in nuclear-power industry of the world. ASME Journal of Nuclear Engineering and Radiation Science. 2019;**5**(1):27. Available from: http://nuclearenginee ring.asmedigitalcollection.asme.org/a

rticle.aspx?articleID=2718229

806-817.pdf

lications

**37**

[5] Pioro I, Kirillov P. Current status of electricity generation at nuclear power plants. In: Méndez-Vilas A, editor. Materials and Processes for Energy: Communicating Current Research and Technological Developments, Energy Book Series #1. Spain: Formatex Research Center; 2013. pp. 806-817. Available from: http://www.formatex. info/energymaterialsbook/book/

[6] Handbook of Generation IV Nuclear Reactors. Pioro IL, editor. Duxford, UK: Elsevier, Woodhead Publishing (WP); 2016. pp. 940. Available from: https:// www.gen-4.org/gif/jcms/c\_9373/pub

[7] Dragunov A, Saltanov E, Pioro I, Kirillov P, Duffey R. Power cycles of
