scholarly journals THEORETICAL INVESTIGATION OF HEAT PRODUCTION FEASIBILITY BY MEANS OF WIND MECHANICAL PLANTS

2021 ◽  
pp. 355-361
Author(s):  
Holovko Volodimir ◽  
Kohanevich Volodimir ◽  
Shikhailov Mikola ◽  
Sukmaniuk Olena ◽  
Kukharets Savelii
Keyword(s):  
Heat Transfer ◽  
Wind Speed ◽  
Closed Loop ◽  
Mechanical Energy ◽  
Heat Energy ◽  
Heat Transfer Fluid ◽  
Cycle Duration ◽  
Centrifugal Fan ◽  
Heat Transfer Fluids ◽  
The Given

A widespread use of wind turbines can fully or partly provide energy for the consumers, but with due regards to certain investments and instability of energy generation. Technologies of using wind energy imply the conversion of the mechanical energy of a wind flow into the electrical or heat energy. The work is concerned with the estimation of the amount of heat in the process of heating liquid coolants and heat-transfer fluids when using wind mechanical plants. In the paper was made a numerical analysis of the temperature rise of the liquid which circulates in a closed loop of a gear-type pump, whose productivity is 3 l/m and which is driven by a wind turbine 5 kW of power capacity under a nominal wind speed of 7 m/s and under cycle duration of 2 s. The analysis showed that the temperature increased by 0.290 °К/s. If such wind speed is observed during one hour, the temperature of 100 kg of water will increase by 8.1°С. Heating of a heat-transfer fluid with a supply of mechanical energy to a working part can be achieved by a centrifugal fan. Assuming that the given process occurs without supplying and removing heat energy (it is adiabatic), for the capacity of 1.5 kW and under the revolution in a range of 1000….3000 r/m, the changes in temperature will range from 0.38 to 0.87 °К/s, but for the capacity of 7.5 kW and under 750 – 1500 r/m, the changes in temperature will range from 0.56 to 1.23 °К/s.

A Brief Review on Thermal Behaviour of PANI as Additive in Heat Transfer Fluid

2021 ◽  
Vol 02 (01) ◽  
Author(s):  
A.G.N. Sofiah ◽  
◽  
M. Samykano ◽  
S. Shahabuddin ◽  
K. Kadirgama ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Thermal Properties ◽  
Conducting Polymers ◽  
Volume Fraction ◽  
Corrosion Property ◽  
Environmental Stability ◽  
Heat Transfer Fluid ◽  
Thermal Engineering ◽  
Engineering System ◽  
Heat Transfer Fluids

Since a decade ago, investigation on nanofluids has grown significantly owing to its enhanced thermal properties compared to conventional heat transfer fluids. This engineered nanofluid has been widely used in the thermal engineering system to improve their energy consumption by improving the thermal efficiency of the system. The addition of nano-size particles as additives dispersed in the base fluids proved to significantly either improve or diminish the behaviour of the base fluids. The behaviour of the base fluid highly depends on the properties of the additives material, such as morphology, size, and volume fraction. Among the variety of nanoparticles studied, the conducting polymers have been subject of high interest due to its high environmental stability, good electrical conductivity, antimicrobial, anti-corrosion property and significantly cheap compared to other nanoparticles. As such, the main objective of the present review is to provide an overview of the work performed on thermal properties performance of conducting polymers based nanofluids.

scholarly journals Contribution to the Parametric Study of the Performance of A Parabolic Trough Collector

2021 ◽  
Vol 321 ◽  
pp. 02016
Author(s):  
Belkacem Bouali ◽  
Hanane-Maria Regue
Keyword(s):  
Heat Transfer ◽  
Mass Flow ◽  
Flow Rate ◽  
Optimal Operation ◽  
Heat Transfer Fluid ◽  
Parabolic Trough ◽  
Parabolic Trough Collector ◽  
Heat Transfer Fluids ◽  
Ansys Cfx ◽  
Different Seasons

This paper presents an analysis of the performance of a parabolic trough collector (PTC) according to some key operating parameters. The effects of the secondary reflector, the length and thickness of the absorber tube (receiver tube) and the flow rate of the heat transfer fluid (HTF) are investigated. The main objective is to determine an optimal operation, which improves the performance of a traditional PTC. The target variables are the temperature at the outlet of the tube, the amount of energy collected by the HTF and the efficiency of the system. The solar flux data concern the city of LAGHOUAT located in the south of Algeria. Four days in different seasons are considered. The optical analysis of the system is performed by using the open source SolTrace code. The output of this analysis is used as a boundary condition for the CFD solver. The conjugate heat transfer and the fluid flow through the absorber tube are simulated by using ANSYS-CFX solver. Water is considered as heat transfer fluids. The obtained results show that the use of a curved secondary reflector significantly improves the performance of the traditional PTC. As the thickness of the tube increases, the heat storage in the material increases, which increases the temperature at the exit of the tube and therefore the efficiency of the system. However, the length of the tube depends on the mass flow of the HTF and vice versa. To keep the efficiency constant by choosing another length, it is necessary to choose a mass flow rate proportional to the flow rate corresponding to the initial length.

The Design of a Meter to Measure the Mass Flow-Specific Heat Product of a Heat Transfer Fluid

1986 ◽  
Vol 108 (2) ◽  
pp. 117-122 ◽  
Author(s):  
D. Proctor
Keyword(s):  
Heat Transfer ◽  
Specific Heat ◽  
Mass Flow ◽  
Closed Loop ◽  
Calibration Procedure ◽  
Loop System ◽  
Heat Transfer Fluid ◽  
Closed Loop System ◽  
Operating Range

This paper describes the design and calibration of a device for measuring the mass flow-specific heat (m˙Cp) product of a heat transfer fluid in situ in a closed loop system. Accuracy of the meter is ±0.07 percent to ±0.12 percent over its operating range of 18 to kW K−1, depending on the calibration procedure which has to be adopted.

Stability of Nanofluids

2013 ◽  
Vol 757 ◽  
pp. 139-149 ◽  
Author(s):  
Hema Setia ◽  
Ritu Gupta ◽  
R.K. Wanchoo
Keyword(s):  
Heat Transfer ◽  
Base Fluid ◽  
Thermal Characteristics ◽  
Solid Particles ◽  
Heat Transfer Fluid ◽  
Published Data ◽  
Heat Transfer Fluids ◽  
Fluid Systems ◽  
Agglomeration Of Nanoparticles ◽  
The Stability

It has long been established that a suspension of nanosized solid particles in liquids provide useful advantages in industrial heat transfer fluid systems. Numerous investigations on nanofluids show a significant enhancement in thermal conductivity over the base fluid in which these nanoparticles are dispersed. However, the stability of the suspension is critical in the development and application of these new kind of heat transfer fluids. Rather, high discrepancy in the published data for the same nanoparticles on the physical and thermal characteristics of nanofluids is primarily due to different methods adopted by different researchers to obtain stable nanofluids. Sedimentation and agglomeration of nanoparticles in nanofluids and their dispersion stability has not been well addressed in the literature. Hence, there is a need to establish a standard method of preparation of these nanofluids so as to obtain a unified data which can eventually be utilized for the application of nanofluids. This chapter focuses on the stability of nanofluids prepared via two step process. Different parameters that affect the stability of nanofluids have been discussed. Different techniques that have been used for the evaluation of the stability characteristics of nanofluids have been elucidated.

Analytical Modeling and Experimental Measurements of Ternary Molten Salt Heat Transfer Fluids for Energy Applications

2012 ◽  
Author(s):  
Kevin Coscia ◽  
Sudhakar Neti ◽  
Alparslan Oztekin ◽  
Tucker Elliot ◽  
Satish Mohapatra
Keyword(s):  
Heat Transfer ◽  
Heat Transfer Fluid ◽  
Scanning Calorimetry ◽  
Energy Applications ◽  
Gas Processing ◽  
Heat Transfer Fluids ◽  
Melting Temperatures ◽  
High Temperature Processes ◽  
Freezing Temperatures ◽  
Current Energy

One of the major impediments of current energy applications is the availability of an economical and reliable heat transfer fluid. Such applications include concentrated solar power, gas processing, petrochemicals, nuclear, and other high-temperature processes. Organic heat transfer fluids currently in use have limitations approaching 390°C, and other salt-based fluids have rather high freezing temperatures. Ternary nitrate salts have the potential to operate at high temperatures while maintaining low freezing temperatures. Some melting temperatures of LiNO3-NaNO3-KNO3 salt mixtures as a function of LiNO3 composition have been investigated using differential scanning calorimetry. Phase diagrams have also been predicted for the LiNO3-NaNO3-KNO3, CsNO3-NaNO3-KNO3, and CsNO3-LiNO3-KNO3 systems using mathematical modeling and the results are encouraging. The results presented in this work are expected to make a significant impact on the development of economical and practical ternary nitrate mixtures in energy applications.

Hydronic Coil Performance Evaluation With Nanofluids and Conventional Heat Transfer Fluids

2009 ◽  
Vol 1 (1) ◽  
Author(s):  
Roy Strandberg ◽  
Debendra K. Das
Keyword(s):  
Heat Transfer ◽  
Base Fluid ◽  
Finned Tube ◽  
Heat Transfer Fluid ◽  
Al2o3 Nanoparticles ◽  
Heat Transfer Medium ◽  
Heating Coil ◽  
Heat Transfer Fluids ◽  
Heating Capacity ◽  
Coil Performance

The performance of hydronic heating coils with nanoparticle enhanced heat transfer fluids (nanofluids) is evaluated and compared with their performance with a conventional heat transfer fluid comprised of 60% ethylene glycol (EG) and 40% water, by mass (60% EG). The nanofluids analyzed are comprised of either CuO or Al2O3 nanoparticles dispersed in the 60% EG solution. The heating coil has a finned tube configuration commonly used in commercial air handling and ventilating systems. Coil performance is modeled using methods that have been previously developed and validated. The methods are modified by incorporating Nusselt number correlations for nanofluids that have been previously documented in the literature. Similarly, correlations for nanoparticle thermophysical properties that have been documented in the literature are employed. The analyses show that heating coil performance may be enhanced considerably by employing these nanofluid solutions as a heat transfer medium. The model predicts a 16.6% increase in coil heating capacity under certain conditions with the 4% Al2O3/60% EG nanofluid, and a 7.4% increase with the 2% CuO/60% EG nanofluid compared with heating capacity with the base fluid. The model predicts that, for a coil with the Al2O3/60% EG nanofluid, liquid pumping power at a given heating output is reduced when compared with a coil with the base fluid.

Post-Industrial Ceramics Compatibility With Heat Transfer Fluids for Low-Cost Thermal Energy Storage Applications in CSP

2012 ◽  
Author(s):  
Nicolas Calvet ◽  
Antoine Meffre ◽  
Judith C. Gomez ◽  
Abdessamad Faik ◽  
Régis Olivès ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Energy Storage ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Low Cost ◽  
Heat Transfer Fluid ◽  
Medium Temperature ◽  
Heat Transfer Fluids ◽  
Post Industrial ◽  
Temperature Applications

This paper investigates the possibility of using a post-industrial ceramic commercially called Cofalit as a promising, sustainable, and inexpensive ($10/ton) thermal energy storage material. This ceramic presents relevant properties to store thermal energy by means of sensible heat in the temperature range of concentrated solar power (CSP) plants from ambient temperature up to 1100 °C. In the present study, the compatibility of this ceramic was studied with two conventional heat transfer fluids: nitrate molten salts for medium-temperature applications (200 to 500 °C) and air for high-temperature applications (500 to 900 °C). The use of this ceramic in direct contact with the heat transfer fluid should significantly reduce the cost of thermal energy storage systems in CSP applications and help to achieve the U.S. Department of Energy’s SunShot Initiative cost targets.

Experimental Investigation to the Properties of Eutectic Salts by NaCl-KCl-ZnCl2 for Application as High Temperature Heat Transfer Fluids

2014 ◽  
Author(s):  
Kai Wang ◽  
Edgar Molina ◽  
Ghazal Dehghani ◽  
Ben Xu ◽  
Peiwen Li ◽  
...  
Keyword(s):  
Heat Transfer ◽  
High Temperature ◽  
Melting Point ◽  
Vapor Pressure ◽  
Mole Fraction ◽  
Heat Transfer Fluid ◽  
Test Facility ◽  
Vapor Pressures ◽  
Heat Transfer Fluids ◽  
Temperature Heat

A group of eutectic ternary halide salts were surveyed and studied for the objective of developing a high temperature heat transfer fluid with a freezing point below 250°C and a low vapor pressure, below 1.0 atm, at temperatures up to 800°C. The studied salts include: 1) NaCl-KCl-ZnCl2 with a mole fractions of 18.6%-21.9%-59.5% and a melting point of tm=213°C; 2) NaCl-KCl-ZnCl2 with a mole fraction of 13.4%-33.7%-52.9% and a melting point of tm=204°C; and 3) NaCl-KCl-ZnCl2 with mole fraction of 13.8%-41.9%-44.3% and a melting point of tm=229 °C. Vapor pressures of these salts at different temperatures were experimentally obtained using an in-house developed test facility. The results show that vapor pressures of all the three eutectic molten salts are below 1.0 atm at a temperature of 800 °C. The salt of ZnCl2-KCl-NaCl in mole faction of 44.3%-41.9%-13.8% has lowest vapor pressure which is only about 1.0 atm even at a temperature of 900 °C. Viscosities of these salts were measured in the temperature range from after melting to 850°C. At low temperatures near their melting points of the salts, the viscosities are about 16 × 10−3Pa s, while at high temperatures above 700°C the viscosities are around 4 × 10−3Pa s, which is satisfactorily low to serve as heat transfer fluid for circulation in a CSP system. Both the vapor pressure and the viscosities of the studied three eutectic salts demonstrated satisfaction to serve as high temperature heat transfer fluids. Other thermal and transport properties of these salts are expected to be reported in the future for screening out a satisfactory high temperature heat transfer fluid.

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