Effects of thermophysical, hydrodynamics and thermal characteristics of well stable metallic nanofluids on energy transportation

• Main Authors: Ahmed, Waqar, Sidik, Nor Azwadi Che, Mehmood, Shahid, Alam, Mir Waqas, Fayaz, H., Hussain, Muhammad Iqbal, Alawi, Omer A., Ahmed, Syed Muzamil, Shah, Syed Nadeem Abbas, Kazi, S. N.
• Format: Article
• Published: SPRINGER 2022
• Subjects: TJ Mechanical engineering and machinery
• Online Access: http://eprints.um.edu.my/46172/; https://doi.org/10.1007/s10973-022-11696-8

The current research focuses on the chemical synthesis of ZnO and preparation of ZnO dispersed in EG@DW mixture-based nanofluids for the investigation of enhancement in heat transfer of a square shaped heat exchanger. The steady and uniform dispersion of ZnO nanoparticles was achieved using high probe sonication at varying mass% concentrations like (0.1; 0.075; 0.05 and 0.025 mass%). Also, the ZnO particles were synthesized using sonochemical technique, where sodium hydroxide (NaOH) and zinc acetate (ZnC4H6O4) were used as raw materials. For the verification of ZnO synthesis numerous characterizations like UV-Vis, XRD, FTIR, and FESEM analysis were carried out. The changed mass% concentrations of ZnO-EG@DW-based nanofluids were considered to check their effects on thermophysical properties, dispersion, stability, and heat transfer (Nusselt Numbers) at varying Reynolds numbers ranging from 4550 to 20,360 using square heat exchanger. A positive increase in thermal conductivity was observed by the addition of ZnO in the ZnO-EG@DW with (50:50) mixture. The highest thermal conductivity of 1.0 W m(-1) K-1 was noticed at a maximum of 0.1 mass% concentration which is greater than base fluid (EG@DW) at 45 degrees C. The maximum pressure drop of 2400 Pa m(-1) at Reynold number 20360 and higher friction loss of 0.045 for Reynolds number 4550 was noticed at 0.1 mass% concentration. The highest improvement in heat transfer was recorded at 0.1 mass% is 550-2830 W m(-1) K which is 63% greater of the base fluid, while others mass% illustrate improved heat transfer coefficient of about 550-2170, 550-1750, and 550-1500 W M-2 K-1, respectively, at highest Reynolds (Re) when it compared with the base fluid (EG@DW). All the heat transfer related experiments were executed at 30 degrees C room temperature where constant heat flux of 10,886 W M-2 and eight varying flow rates were used. GRAPHICS] .