Numerical investigation of heat transfer at a rectangular channel with combined effect of nanofluids and swirling jets in a vehicle radiator

The present work is focused on the Graphene-based nanofluids with high thermal conductivity which helps to improve the performance and enhance heat transfer. The thermal systems emphasis on the fluid coolant selection and statistical model. Graphene is a super-material, lighter than air, high thermal conductivity, and chemical stability. The purpose of the research is to work up with Graphene-based Nanofluids i.e., Graphene (G) and Graphene oxide (GO). Nanoparticles are dispersed in a base fluid with a 60:40 ratio Water & Ethylene Glycol and at different volume concentrations ranging from 0.01%-0.09%. Radiator model is designed in modelling software and louvered strip is inserted. The simulation (Finite Element Analysis) is performed to evaluate variation in temperature drop, enthalpy, entropy, heat transfer coefficient and total heat transfer rate of the considered nanofluids, results were compared by with and without louvered strip in the radiator for the temperature absorption. 58-60% enhancement of enthalpy observed when Graphene and Graphene oxide nanofluid was utilized. 1.8% enhancement of entropy is observed in 0.09% volume concentration of the Graphene and Graphene oxide nanofluid when louvered strips are inserted in the radiator tube at a flow rate of 3 LPM. With louvered strip inserted in the radiator, heat transfer coefficient enhanced by 236% for Graphene and 320% enhancement is identified for Graphene oxide nanofluid when compared to without louvered strip insert. The results stated that high performance is observed with the utilization of louvered strip in the radiator tube.

Section: Introductionmentioning

confidence: 99%

Heat transfer performance of a radiator with and without louvered strip by using Graphene-based nanofluids

Sandhya

Ramasamy

Sudhakar

et al. 2021

“…Several experimental studies related to thermal conductivity (TC) [2][3][4][5], convective heat transfer (CHT) [6][7][8], and heat absorption rate [9] were reported with possibilities to use nanofluids in heat transfer applications. Heat transfer studies using numerical techniques have proved the possibilities of improving the heat transfer [10][11][12][13].Thermal conductivity is one of the property of a nanofluid which is essential for the evaluation of heat transfer coefficient under different flow condition and operating temperature. This property of fluid changes with the volume concentration, size of the nanoparticles and temperature of the nanofluid [14].…”

Section: Introductionmentioning

confidence: 99%

Experimental investigation on thermal conductivity and stability of water-graphite nanofluid

Yashawantha

Vinod

2021

Enhanced thermal conductivity of nanofluids has proven importance in enhancing heat transfer for many application. In this study, thermal conductivity of graphite nanopowder dispersed in water at different temperatures was studied experimentally. Stable nanofluids of different concentrations (0.2 vol%, 0.5 vol%, 0.8 vol%, 1 vol% and 1.5 vol%) are prepared using ultrasonic cleaner by sonicating for 3 hour. Thermal conductivity was measured from temperature 25 to 55 ºC with an interval of 5 ºC using KD2 Pro thermal properties analyser. Experimental results showed that thermal conductivity increases with increase in temperature and volume concentration. Thermal conductivity of Water – Graphite nanofluid showed enhancement of 5.6% to 20.42% for 0.2 vol% to 1.5 vol% of concentration at 25 ºC respectively. However, the maximum improvement of 39.72% was found at 1.5% of concentration at 55 ºC compared to water. A correlation was developed considering the effect of temperature and concentration using the regression method. The proposed correlation effectively predicts the thermal conductivity of Water – Graphite nanofluids with an accuracy of ±2.8%.

“…As a result, they found that the thermal resistance of the system decreased by 32.5% compared to the use of pure water. Kilic and Abdulvahitoglu [12] studied on numerical investigation of heat transfer with nanofluids and swirling jets in a vehicle radiator. As a base coolant Al 2 O 3 -H 2 O nanofluid was chosen for all parameters.…”

Section: Introductionmentioning

confidence: 99%

Numerical investigation of effect of different parameter on heat transfer for a crossflow heat exchanger by using nanofluids

Kılıç

Ullah

2021

Self Cite

The heat loads on electronic systems of an unmanned air vehicle are a significant problem. So enhancing heat transfer is a critical key to solve these thermal problems. This study is focused on increasing heat transfer rate in a crossflow heat exchanger by using nanofluids numerically. Effects of different Reynolds number of hot fluid (Re = 6000, 8000, 10000, 12000), different inlet velocity (V air,inlet = 30, 45, 60, 90 m/s) of cooling fluid, temperature of cooling air at different altitude (T air,inlet = 15, 10, 4, -17°C) and different types of nanofluids (Cu-H 2 O, CuO-H 2 O, TiO 2 -H 2 O, H 2 O) on heat transfer were studied numerically. Realizable k-ε turbulence model of ANSYS FLUENT computational fluid dynamics code was used for numerical analysis. It was obtained that increasing Reynolds number from Re = 6000 to 12000 causes an increase of 44.65% on average Nusselt Number. Increasing inlet velocity of cooling air from 30 m/s to 90 m/s causes an increase of 6.96% on average Nusselt number. Increasing or decreasing air inlet temperature at different attitude does not cause any significant change on average Nusselt number. Using Cu-H 2 O nanofluid, which shows the best performance, causes an increase of 6.63% on average Nusselt number according H 2 O. Numerical results were also compared with experimental results at literature. It was obtained that numerical model can represent experimental results in a good level.