Enhancement in pool boiling heat transfer of ethanol and nanofluid on novel supersonic nanoblown nanofiber textured surface

ABSTRACT

Pool boiling of ethanol and Cu-nanofluid was investigated on bare and novel supersonic nanoblown polymer nanofiber nanotextured copper surface. Significant improvement in early ONB (2°C reduction), CHF (23.5%), and BHTC (~2–2.5 times) were achieved in nanotextured surface than bare one. Boiling of nanofluids led to the degradation of ONB and BHTC, with an increase in CHF by 16.7%. Synergistic effect of nanofluid boiling on nanotextured surface led to remarkable enhancement of CHF (44%), BHTC (>2.5 times), and ONB (3°C reduction). The nanofluid and nanotexture aided in ONB and CHF via enhancing nucleation sites, liquid overheating, bubble chopping, and surface wettability.

KEYWORDS:

• supersonic nanoblown nanofibers
• CHF
• BHTC
• nanofluid
• kickback

Nomenclature

cp	=	Specific heat of working liquid (kJ/kgK)
Csf	=	Surface fluid combination factor
Dd	=	Diameter of departing bubble (mm)
fd	=	Frequency of departing bubble (s−1)
g	=	Gravitational constant (m/s2)
h	=	Heat transfer coefficient (kW/m2K)
hfg	=	Latent heat of vaporisation (kJ/kg)
$\mathrm{K}$	=	Thermal conductivity (kW/mK)
$\rho$	=	Density (kg/m3)
Pr	=	Prandtl number
q”	=	Heat flux (kW/m2)
Ts	=	Temperature at the copper surface (K)

Acknowledgments

The work was supported by DST-SERB [ECR/2017/001511(IITM/SERB/SSR/215)]. S.S.T and A.K. acknowledge the scholarship from Ministry of Human Resource Development (MHRD), Govt. of India. The support from the Advanced Materials Research Centre (AMRC), IIT Mandi, and Center for Design and Fabrication of Electronic Devices (C4DFED), IIT Mandi for the sophisticated instrument facility is gratefully acknowledged.

Disclosure statement

The autors declare no conflict of interest.

Supplementary material

Supplemental data for this article can be accessed on the publisher’s website

Additional information

Funding

This work was supported by the DST-SERB [ECR/2017/001511], Govt. of India.