scholarly journals Multi-objective optimization of thermophysical properties of f–Al2O3 nano-dispersions in heat transfer oil

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Abulhassan Ali ◽  
Suhaib Umer Ilyas ◽  
Mohd Danish ◽  
Aymn Abdulrahman ◽  
Khuram Maqsood ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Specific Heat ◽  
Vital Role ◽  
Primary Objective ◽  
Measured Temperature ◽  
Temperature Dependent ◽  
Transfer Operation ◽  
Thermal Oil

AbstractNanofluids are proven to be the next-generation smart fluids with tunable thermal and viscous properties. Nanomaterial concentration plays a vital role in determining the heat transfer and viscous transport characteristics. An optimum concentration is generally required to regulate a feasible and economical heat transfer operation. This research involves the modeling and optimizing different temperature-dependent thermal and viscous parameters for varying concentrations of nanofluids. The nanofluids consist of functionalized alumina (f–Al2O3) nano-dispersions in thermal oil (highly refined mineral oil). The experimentally measured temperature-dependent nanofluids' properties are used to optimize thermophysical parameters using Response Surface Methodology. Two case studies/scenarios are considered in the present research, where the primary objective is to maximize thermal conductivity for heat transfer applications and minimize nanoparticle loadings for economical operation. The input parameters include temperature and nanoparticle loadings. The output parameters or response include thermal conductivity, viscosity, density, and specific heat of nanofluids. For case study 1, the optimal findings for the thermal conductivity, viscosity, density, and specific heat are 0.146061 W/m °C, 0.031889 Pa.s, 838.529 kg/m3 and 1533.9 j/kg °C, respectively. For case study 2, the optimal findings for thermal conductivity, viscosity, density, and specific heat are 0.13476 W/m °C, 0.0226062 Pa.s, 831.071 kg/m3 and 1791.14 j/kg °C, respectively. Although the optimal value for thermal conductivity decreased in case study 2, the nanoparticle weight % was reduced from 1 to 0.322473%.

Heat Transfer Properties of Engine Oils

2005 ◽  
Author(s):  
Scott Wrenick ◽  
Paul Sutor ◽  
Harold Pangilinan ◽  
Ernest E. Schwarz
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Diesel Engine ◽  
Specific Heat ◽  
Mineral Oil ◽  
Engine Oil ◽  
Group V ◽  
Engine Oils ◽  
Heat Transfer Fluids ◽  
Transfer Properties

The thermal properties of engine oil are important traits affecting the ability of the oil to transfer heat from the engine. The larger the thermal conductivity and specific heat, the more efficiently the oil will transfer heat. In this work, we measured the thermal conductivity and specific heat of a conventional mineral oil-based diesel engine lubricant and a Group V-based LHR diesel engine lubricant as a function of temperature. We also measured the specific heat of ethylene glycol. The measured values are compared with manufacturers’ data for typical heat transfer fluids. The Group V-based engine oil had a higher thermal conductivity and slightly lower specific heat than the mineral oil-based engine oil. Both engine oils had values comparable to high-temperature heat transfer fluids.

Review of Nanofluids and Their Biomedical Applications

2021 ◽  
Vol 10 (4) ◽  
pp. 463-477
Author(s):  
Eyad M. Hamad ◽  
Aseel Khaffaf ◽  
Omar Yasin ◽  
Ziad Abu El-Rub ◽  
Samer Al-Gharabli ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Biomedical Applications ◽  
Orthopedic Implants ◽  
Vital Role ◽  
Synthesis Methods ◽  
Suspension Stability ◽  
Stability Enhancement ◽  
Transfer Properties ◽  
Engineering Industries

Numerous researchers have reported significant improvements in nanofluid (NF) heat transfer (HT), suspension stability, thermal conductivity (TC), and rheological and mass transfer properties. As a result, nanofluids (NFs) play an important role in a variety of applications, including the health and biomedical engineering industries. The majority of the nanofluids (NFs) literature focuses on analyzing and comprehending the behavior of nanofluid models as heating or cooling mechanisms in various fields. This article represents a comprehensive study on nanofluids (NFs). It involves commonly used nanoparticles (NPs), magnetic nanofluids (MNFs), thermal conductivity (TC) enhancement, heat transfer (HT) enhancement, nanofluids (NFs) synthesis methods, stability evaluation methods, stability enhancement, nanofluids (NFs) applications in the biomedical field, and their impact on health and the environment. Nanofluids (NFs) play vital role in biomedical applications. It can be implemented in drug delivery systems, hyperthermia, sterilization processes, bioimaging, lubrication of orthopedic implants, and micro-pumping systems for drugs and hormones.

Forced Convection Heat Transfer of Nanofluids: A Review

2017 ◽  
Author(s):  
Aditya Kuchibhotla ◽  
Debjyoti Banerjee
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Thermal Conductivity ◽  
Heat Capacity ◽  
Heat Transfer Coefficient ◽  
Transfer Coefficient ◽  
Specific Heat ◽  
Forced Convection ◽  
Convection Heat Transfer ◽  
Convection Heat

Stable homogeneous colloidal suspensions of nanoparticles in a liquid solvents are termed as nanofluids. In this review the results for the forced convection heat transfer of nanofluids are gleaned from the literature reports. This study attempts to evaluate the experimental data in the literature for the efficacy of employing nanofluids as heat transfer fluids (HTF) and for Thermal Energy Storage (TES). The efficacy of nanofluids for improving the performance of compact heat exchangers were also explored. In addition to thermal conductivity and specific heat capacity the rheological behavior of nanofluids also play a significant role for various applications. The material properties of nanofluids are highly sensitive to small variations in synthesis protocols. Hence the scope of this review encompassed various sub-topics including: synthesis protocols for nanofluids, materials characterization, thermo-physical properties (thermal conductivity, viscosity, specific heat capacity), pressure drop and heat transfer coefficients under forced convection conditions. The measured values of heat transfer coefficient of the nanofluids varies with testing configuration i.e. flow regime, boundary condition and geometry. Furthermore, a review of the reported results on the effects of particle concentration, size, temperature is presented in this study. A brief discussion on the pros and cons of various models in the literature is also performed — especially pertaining to the reports on the anomalous enhancement in heat transfer coefficient of nanofluids. Furthermore, the experimental data in the literature indicate that the enhancement observed in heat transfer coefficient is incongruous compared to the level of thermal conductivity enhancement obtained in these studies. Plausible explanations for this incongruous behavior is explored in this review. A brief discussion on the applicability of conventional single phase convection correlations based on Newtonian rheological models for predicting the heat transfer characteristics of the nanofluids is also explored in this review (especially considering that nanofluids often display non-Newtonian rheology). Validity of various correlations reported in the literature that were developed from experiments, is also explored in this review. These comparisons were performed as a function of various parameters, such as, for the same mass flow rate, Reynolds number, mass averaged velocity and pumping power.

Thermal and Electrical Transport Measurements of Single-Walled Carbon Nanotube Strands

2003 ◽  
Vol 788 ◽  
Author(s):  
Diana-Andra Borca-Tasciuc ◽  
Yann LeBon ◽  
Claire Nanot ◽  
Gang Chen ◽  
Theodorian Borca-Tasciuc ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Carbon Nanotube ◽  
Electrical Properties ◽  
Specific Heat ◽  
Electrical Transport ◽  
Published Data ◽  
Temperature Dependent ◽  
Single Walled Carbon Nanotube ◽  
Single Walled Carbon ◽  
Temperature Dependent Properties

ABSTRACTThis work reports temperature dependent thermal and electrical properties characterization of long (mm size) single-walled carbon nanotube strands. Electrical properties are measured using a 4-probe method. Thermal conductivity and specific heat capacity are determined using an AC driven, self-heating method. Normalized values of resistivity, thermal conductivity, specific heat, thermal diffusivity, and the temperature coefficient of resistance are reported. The trends observed in the temperature dependent properties are comparable with previously published data on multi-walled carbon nanotube strands measured with a similar technique.

Thermal Conductivity and Specific Heat Evaluation of Tissue Using Laser

2020 ◽  
Vol 1002 ◽  
pp. 303-310
Author(s):  
Sudad Issam Younis ◽  
Haqi I. Qatta ◽  
Mohammed Jalal Abdul Razzaq ◽  
Khalid S. Shibib
Keyword(s):  
Heat Transfer ◽  
Thermal Conductivity ◽  
Thermal Properties ◽  
Specific Heat ◽  
Iterative Procedure ◽  
Input Data ◽  
Maximum Error ◽  
Heat Transfer Analysis ◽  
Long Wavelength ◽  
Inverse Heat Transfer

In this work, an inverse heat transfer analysis was used to determine thermal conductivity and specific heat of tissue using special iteration. A laser with a long wavelength was utilized to impose heat to the tissue. The heat that induced in the sample causes an increase in the temperature of a tissue which is measured by a thermocouple. The readings were used together with that analytically obtained from the solution of the heat equation in an iterative procedure to obtain the thermal properties of tissue. By using this method, accurate thermal conductivity and specific heat of tissue could be obtained. It was found that the maximum error in output result and the error in input data were in the same order and that there was a linear relationship between output and input errors.

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