Krishna Kondakrindi, M. Reddigari, Hemachandra Konireddy, U. Maheswari
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引用次数: 1
Abstract
The present work aims to exploit the thermal performance of a packed bed of combined sensible & latent heat of storage unit with an integrated solar heat source. A cylindrical insulated storage tank in the Thermal Energy Storage (TES) unit is filled with spherical capsules separately which contains phase change material (PCM) as paraffin wax and stearic acid. The PCM usage has the benefits that it can be used as a thermal management tool and it reduces the cost and size of the system as it offers higher isothermal behavior and thermal storage capacity. The thermal conductivity of heat transfer fluid (HTF) can be enhanced by using nanoparticles mixed in water. Nanofluids are the more efficient fluids for the applications of heat-transfer. The water based nanofluids are used to transfer heat between the solar collector and storage tank which is a sensible heat storage material. The HTF materials are varied and Experimental trials have been conducted separately. Experimentation was carried out First by considering only water as HTF and is extended by adding water with one of the Nanomaterials- i.e.TiO2 and CuO, each in 3 HTF volume % as 0.2, 0.5 & 0.8. The variable source of heat supply considered is Solar flat plate collector. The study was transpired by varying the flow rates of nanofluids as 2.0, 4.0 and 6.0 l/min. The novelty of this work is to envisage the enhancement of heat transfer and to study the effects on the melting time of the PCMs of these fluids which were carried out. The performance parameters like charging time and system efficiency, instantaneous stored heat, cumulative stored heat were studied for the different HTFs and for the PCMs-paraffin and stearic acid. The batch wise process experiments for Discharging were carried out to recover the heat stored, and the results are presented.
期刊介绍:
The main aims of Thermal Science
to publish papers giving results of the fundamental and applied research in different, but closely connected fields:
fluid mechanics (mainly turbulent flows), heat transfer, mass transfer, combustion and chemical processes
in single, and specifically in multi-phase and multi-component flows
in high-temperature chemically reacting flows
processes present in thermal engineering, energy generating or consuming equipment, process and chemical engineering equipment and devices, ecological engineering,
The important characteristic of the journal is the orientation to the fundamental results of the investigations of different physical and chemical processes, always jointly present in real conditions, and their mutual influence. To publish papers written by experts from different fields: mechanical engineering, chemical engineering, fluid dynamics, thermodynamics and related fields. To inform international scientific community about the recent, and most prominent fundamental results achieved in the South-East European region, and particularly in Serbia, and - vice versa - to inform the scientific community from South-East European Region about recent fundamental and applied scientific achievements in developed countries, serving as a basis for technology development. To achieve international standards of the published papers, by the engagement of experts from different countries in the International Advisory board.