Using experimental data to estimate the heat transfer and pressure drop of non-Newtonian nanofluid flow through a circular tube: Applicable for use in heat exchangers

2018 ◽  
Vol 129 ◽  
pp. 1573-1581 ◽  
Author(s):  
Ehsan Shahsavani ◽  
Masoud Afrand ◽  
Rasool Kalbasi
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Pressure Drop ◽  
Heat Exchangers ◽  
Circular Tube ◽  
Nanofluid Flow ◽  
Flow Through

scholarly journals Experimental study on turbulent convective heat transfer, pressure drop, and thermal performance characterization of ZnO/water nanofluid flow in a circular tube

2014 ◽  
Vol 18 (4) ◽  
pp. 1315-1326 ◽  
Author(s):  
Ahmad Sajadi ◽  
Seyed Sadati ◽  
Masoud Nourimotlagh ◽  
Omid Pakbaz ◽  
Dariush Ashtiani ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Experimental Study ◽  
Heat Transfer Coefficient ◽  
Pressure Drop ◽  
Thermal Performance ◽  
Base Fluid ◽  
Circular Tube ◽  
Turbulent Regime ◽  
Nanofluid Flow ◽  
Volume Fractions

In this experimental study heat transfer and pressure drop behavior of ZnO/water nanofluid flow inside a circular tube with constant wall temperature condition is investigated where the volume fractions of nanoparticles in the base fluid are 1% and 2%. The experiments? Reynolds numbers ranged roughly from 5000 to 30000. The experimental measurements have been carried out in the fully-developed turbulent regime. The results indicated that heat transfer coefficient increases by 11% and 18% with increasing volume fractions of nanoparticles respectively to 1% and 2% vol. The measurements also showed that the pressure drop of nanofluids were respectively 45% and145% higher than that of the base fluid for volume fractions of 1% and 2% of nanoparticles. However experimental results revealed that overall thermal performance of nanofluid is higher than that of pure water by up to 16% for 2% vol. nanofluid. Also experimental results proved that existing correlations can accurately estimate nanofluids convective heat transfer coefficient and friction factor in turbulent regime, provided that thermal conductivity, heat capacity, and viscosity of the nanofluids are used in calculating the Reynolds, Prandtl, and Nusselt numbers.

Enhancement and Prediction of Heat Transfer Rate in Turbulent Flow Through Tube With Perforated Twisted Tape Inserts: A New Correlation

2011 ◽  
Vol 133 (4) ◽  
Author(s):  
J. U. Ahamed ◽  
M. A. Wazed ◽  
S. Ahmed ◽  
Y. Nukman ◽  
T. M. Y. S. Tuan Ya ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Pressure Drop ◽  
Turbulent Flow ◽  
Heat Transfer Rate ◽  
Transfer Rate ◽  
Circular Tube ◽  
Twisted Tape ◽  
Pumping Power ◽  
Plain Tube ◽  
Flow Through

An experimental investigation has been carried out for turbulent flow in a tube with perforated twisted tape inserts. The mild steel twisted tape inserts with circular holes of different diameters (i.e., perforation) are used in the flow field. An intensive laboratory study is conducted for heat transfer and pressure drop characteristics in the tubes for turbulent flow with various airflow rates. Heat transfer and pressure drop data are engendered for a wide range Reynolds number (1.3×104–5.2×104). Tube wall temperature, pressure drop, air velocity, and its temperature are measured both for plain tube and for tube with perforated twisted tape inserts. Heat transfer coefficients, Nusselt number, pumping power, and heat transfer effectiveness are calculated for both cases. Experimental results showed that perforated twisted inserts of different geometry in a circular tube enhanced the heat transfer rate with an increase in friction factor and pumping power for turbulent flow. The pumping power, heat transfer coefficient, and effectiveness in the tube with the twisted tape inserts are found to increase up to 1.8, 5.5, and 4.0 times of those for the plain tube for same Reynolds number, respectively. Finally, a correlation is developed for prediction of the heat transfer rate for turbulent flow through a circular tube with perforated twisted tape inserts.

scholarly journals Numerical Analysis of The Thermo-Convective Behaviour of an Al2O3-H2O Nanofluid Flow Inside a Channel with Trapezoidal Corrugations

2021 ◽  
Vol 89 (2) ◽  
pp. 114-127
Author(s):  
Mostefaoui Amina ◽  
Saim Rachid ◽  
Abboudi Saïd
Keyword(s):  
Heat Transfer ◽  
Pressure Drop ◽  
Volume Fraction ◽  
High Volume ◽  
Reynolds Numbers ◽  
Constant Heat Flux ◽  
Nanofluid Flow ◽  
Nanoparticle Diameter ◽  
Flow Through ◽  
Volume Method

In this present article, a study of the dynamic and thermal behavior of the Al2O3-water nanofluid flow through a channel provided with trapezoidal undulations, under the action of a constant heat flux. To do this, the effect of various volume fractions (0-4%) and that of the nanoparticle diameter (30, 40, 60 nm) on the heat transfer and pressure drop within the channel was analyzed, for a range of Reynolds numbers between 100 to 1000. The equations governing the fluid flow, namely the equations of continuity, momentum and energy were integrated and discretized based on the finite volume method (FVM). The obtained results indicated that using nanofluids with a high-volume fraction and a small nanoparticle diameter makes it possible to improve the performance of the system in terms of heat transfer, pressure drop and friction factor.

New correlations for wavy plate-fin heat exchangers: different working fluids

2014 ◽  
Vol 24 (5) ◽  
pp. 1086-1108 ◽  
Author(s):  
Morteza Khoshvaght Aliabadi ◽  
Faramarz Hormozi ◽  
Elham Hosseini Rad
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Pressure Drop ◽  
Heat Exchangers ◽  
Cfd Simulation ◽  
Design Parameters ◽  
Geometrical Parameters ◽  
Working Fluids ◽  
Content Type ◽  
Simulation Results

Purpose – The main purpose of this paper is the generation of the heat transfer and pressure drop correlations by considering three working fluids, namely air, water, and ethylene glycol, for the wavy plate-fin heat exchangers (PFHEs). Design/methodology/approach – In order to present the general correlations, various models with different geometrical parameters should be tested. Because of the problems, such as difficult, long time, and costly fabrication of the wavy fins in experimental tests, computational fluid dynamics (CFD) calculations can be a useful method for the generation of the heat transfer and pressure drop correlations with eliminating the experimental problems. Hence, the effective design parameters of the wavy plate-fin, including fin pitch, fin height, wave length, fin thickness, wave amplitude, and fin length, and also their levels were recognized from the literature. The Taguchi method was applied to formulate the CFD simulation work. Findings – The simulation results were compared and validated with an available experimental data. The mean deviations of the Colburn factor, j, and Fanning friction factor, f, values between the simulation results and the experimental data were 3.74 and 9.07 percent, respectively. The presented air correlations and experimental data were in a good agreement, so that approximately 95 percent of the experimental data were correlated within ±12 percent. The j factor values varied for the different working fluids, while the f factor values did not sensibly change. Practical implications – The presented correlations can be used to estimate the thermal-hydraulic characteristics and to design of the compact PFHE with the wavy channels. Originality/value – This manuscript presents the new correlations for the compact PFHEs with the way channels by considering all the geometrical parameters and the working fluids with the different Prandtl numbers, 0.7, 7, and 150.

HEAT TRANSFER AND PRESSURE DROP IN TURBULENT FLOW THROUGH A TUBE WITH LONGITUDINAL PERFORATED STAR-SHAPED INSERTS

2011 ◽  
Vol 18 (6) ◽  
pp. 491-502 ◽  
Author(s):  
Andrew Mintu Sarkar ◽  
M. A. Rashid Sarkar ◽  
Mohammad Abdul Majid
Keyword(s):  
Heat Transfer ◽  
Pressure Drop ◽  
Turbulent Flow ◽  
Flow Through

scholarly journals A MCDM Methodology to Determine the Most Critical Variables in the Pressure Drop and Heat Transfer in Minichannels

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2069
Author(s):  
Eloy Hontoria ◽  
Alejandro López-Belchí ◽  
Nolberto Munier ◽  
Francisco Vera-García
Keyword(s):  
Heat Transfer ◽  
Pressure Drop ◽  
Heat Exchangers ◽  
Saturation Pressure ◽  
Computational Cost ◽  
Urban Systems ◽  
Condensation Process ◽  
Geometrical Parameters ◽  
Maximum Heat ◽  
Maximum Heat Transfer

This paper proposes a methodology aiming at determining the most influent working variables and geometrical parameters over the pressure drop and heat transfer during the condensation process of several refrigerant gases using heat exchangers with pipes mini channels technology. A multi-criteria decision making (MCDM) methodology was used; this MCDM includes a mathematical method called SIMUS (Sequential Interactive Modelling for Urban Systems) that was applied to the results of 2543 tests obtained by using a designed refrigeration rig in which five different refrigerants (R32, R134a, R290, R410A and R1234yf) and two different tube geometries were tested. This methodology allows us to reduce the computational cost compared to the use of neural networks or other model development systems. This research shows six variables out of 39 that better define simultaneously the minimum pressure drop, as well as the maximum heat transfer, saturation pressure fluid entering the condenser being the most important one. Another aim of this research was to highlight a new methodology based on operation research for their application to improve the heat transfer energy efficiency and reduce the CO2 footprint derived of the use of heat exchangers with minichannels.

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