Experimental investigations on the cooling of a motorcycle helmet with phase change material (PCM)

The thermal comfort of motorcycle helmet during hot weather is important as it can affect the physiological and psychological condition of the rider. This paper examines the use of phase change material (PCM) to cool a motorcycle helmet and presents the experimental investigations on the influences of the simulated solar radiation, wind speed, and heat generation rate on the cooling system. The result shows that the PCM-cooled helmet is able to prolong the thermal comfort period compared to a normal helmet. The findings also indicate that the heat generation from the head is the predominant factor that will affect the PCM melting time. Simulated solar radiation and ram-air due to vehicle motion under adiabatic condition can have very little influences on the PCM melting time. The results suggested that the helmet usage time would be influenced by the amount of heat generated from the head. Some major design considerations based on these findings have been included. Although this investigation focuses on the cooling of a motorcyclist helmet, the findings would also be useful for the development of PCM-cooling systems in other applications.

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Thermal Energy Storage Through Melting of a Commercial Phase Change Material in an Annulus with Radially Divergent Longitudinal Fins

International Journal of Thermofluid Science and Technology ◽

10.36963/ijtst.20070102 ◽

2020 ◽

Vol 7 (1) ◽

Author(s):

Tonny Tabassum Mainul Hasan ◽

Latifa Begum

Keyword(s):

Energy Storage ◽

Phase Change ◽

Phase Change Material ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Storage System ◽

Operating Conditions ◽

Melting Time ◽

Bottom Part ◽

Change Material

This study reports on the unsteady two-dimensional numerical investigations of melting of a paraffin wax (phase change material, PCM) which melts over a temperature range of 8.7oC. The PCM is placed inside a circular concentric horizontal-finned annulus for the storage of thermal energy. The inner tube is fitted with three radially diverging longitudinal fins strategically placed near the bottom part of the annulus to accelerate the melting process there. The developed CFD code used in Tabassum et al., 2018 is extended to incorporate the presence of fins. The numerical results show that the average Nusselt number over the inner tube surface, the total melt fraction, the total stored energy all increased at every time instant in the finned annulus compared to the annulus without fins. This is due to the fact that in the finned annulus, the fins at the lower part of the annulus promotes buoyancy-driven convection as opposed to the slow conduction melting that prevails at the bottom part of the plain annulus. Fins with two different heights have been considered. It is found that by extending the height of the fin to 50% of the annular gap about 33.05% more energy could be stored compared to the bare annulus at the melting time of 82.37 min for the identical operating conditions. The effects of fins with different heights on the temperature and streamfunction distributions are found to be different. The present study can provide some useful guidelines for achieving a better thermal energy storage system.

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Latent Heat Thermal Storage of Nano-Enhanced Phase Change Material Filled by Copper Foam with Linear Porosity Variation in Vertical Direction

Energies ◽

10.3390/en14051508 ◽

2021 ◽

Vol 14 (5) ◽

pp. 1508

Author(s):

Mohammad Ghalambaz ◽

Mohammad Shahabadi ◽

S. A. M Mehryan ◽

Mikhail Sheremet ◽

Obai Younis ◽

...

Keyword(s):

Natural Convection ◽

Phase Change ◽

Phase Change Material ◽

Metal Foam ◽

Vertical Direction ◽

Melting Time ◽

Copper Foam ◽

Average Porosity ◽

The Impact ◽

Change Material

The melting flow and heat transfer of copper-oxide coconut oil in thermal energy storage filled with a nonlinear copper metal foam are addressed. The porosity of the copper foam changes linearly from bottom to top. The phase change material (PCM) is filled into the metal foam pores, which form a composite PCM. The natural convection effect is also taken into account. The effect of average porosity; porosity distribution; pore size density; the inclination angle of enclosure; and nanoparticles’ concentration on the isotherms, melting maps, and the melting rate are investigated. The results show that the average porosity is the most important parameter on the melting behavior. The variation in porosity from 0.825 to 0.9 changes the melting time by about 116%. The natural convection flows are weak in the metal foam, and hence, the impact of each of the other parameters on the melting time is insignificant (less than 5%).

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Experimental investigation of thermal energy storage efficiency using fin application with phase change material (PCM) under solar radiation

Heat Transfer Research ◽

10.1615/heattransres.2021036643 ◽

2021 ◽

Author(s):

Adem Acır

Keyword(s):

Experimental Investigation ◽

Energy Storage ◽

Solar Radiation ◽

Phase Change ◽

Phase Change Material ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Storage Efficiency ◽

Energy Storage Efficiency ◽

Change Material

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Three-dimensional computational study in a corrugated pipe inserted system filled with phase change material

International Journal of Numerical Methods for Heat &amp Fluid Flow ◽

10.1108/hff-05-2021-0336 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Ömer Akbal ◽

Hakan F. Öztop ◽

Nidal H. Abu-Hamdeh

Keyword(s):

Phase Change ◽

Phase Change Material ◽

Computational Analysis ◽

Computational Study ◽

Three Dimensional ◽

Simple Algorithm ◽

Melting Time ◽

Geometrical Parameters ◽

Content Type ◽

Change Material

Purpose The purpose of this paper is to make a three-dimensional computational analysis of melting in corrugated pipe inserted system filled with phase change material (PCM). The system was heated from the inner pipe, and temperature of the outer pipe was lower than that of inner pipe. Different geometrical ratio cases and two different temperature differences were tested for their effect on melting time. Design/methodology/approach A computational analysis through a pipe with corrugated pipe filled with PCM is analyzed. Finite volume method was applied with the SIMPLE algorithm method to solve the governing equations. Findings The results indicate that the geometrical parameters can be used to control the melting time inside the heat exchanger which, in turn, affect the energy efficiency. The fastest melting time is seen in Case 4 at the same temperature difference which is the major observation of the current work. Originality/value Originality of this work is to perform a three-dimensional analysis of melting of PCM in a corrugated pipe inserted pipe.

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An experimental study on using polyethylene glycol (PEG) 600 as phase change material for thermal comfort and energy saving in buildings

2018 International Conference on Computer, Control, Electrical, and Electronics Engineering (ICCCEEE) ◽

10.1109/iccceee.2018.8515846 ◽

2018 ◽

Cited By ~ 2

Author(s):

Adil A. M. Omara ◽

Abuelnuor A. A. Abuelnuor ◽

Abdrhaman O. A. Mohammed ◽

Omer M. A. Sirelkhatim ◽

Awab A. M. Suleman

Keyword(s):

Experimental Study ◽

Polyethylene Glycol ◽

Thermal Comfort ◽

Phase Change ◽

Energy Saving ◽

Phase Change Material ◽

Change Material ◽

Peg 600

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The effect of water’s presence around the Phase Change Material

Thermal Science ◽

10.2298/tsci180922301s ◽

2020 ◽

Vol 24 (6 Part B) ◽

pp. 4049-4059 ◽

Cited By ~ 2

Author(s):

Haythem Shili ◽

Kamel Fahem ◽

Souad Harmand ◽

Jabrallah Ben

Keyword(s):

Phase Change ◽

Phase Change Material ◽

Thermal Protection ◽

Flow Direction ◽

Operating Time ◽

Thermal Control ◽

Melting Time ◽

Standard Case ◽

Time Flow ◽

Change Material

As part of the research in the field of thermal control of electronic components, a phase change material is confined in a liquid and is heated vertically on one side by a hot plate. The presence of the liquid around the phase change material prevents the formation of air bubbles produced in case of direct contact between the hotplate and the phase change material (extends the lifetime of the phase change material by reducing overheating zones). It improves heat transfer by increasing the thermal conductivity around the phase change material (raising the thermal exchange surface) and by accelerating the convective transfer. This work examines experimentally and numerically the effect of the water on the phase change material and on the heating plate. The water is used around the phase change material and a comparative study of the comportment of some important parameters like the melt front form, melting time, flow direction, temperature, and operating time is realized. It is found that the presences of the liquid around the phase change material seems to be more interesting for a thermal protection role than the standard case of the phase change material directly heated by the hotplate.

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Electricity-free chemical heater for isothermal nucleic acid amplification with applications in COVID-19 home testing

The Analyst ◽

10.1039/d1an00309g ◽

2021 ◽

Author(s):

Rui Jie Li ◽

Michael G. Mauk ◽

Youngung Seok ◽

Haim H. Bau

Keyword(s):

Nucleic Acid ◽

Phase Change ◽

Phase Change Material ◽

Heat Generation ◽

Temperature Regulation ◽

Nucleic Acid Amplification ◽

Enzymatic Amplification ◽

Isothermal Nucleic Acid Amplification ◽

Home Testing ◽

Change Material

Electricty-free incubation of isothermal enzymatic amplification with a composite comprised of exothermic reactants for heat generation and phase change material for temperature regulation.

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Effect of phase change material using in building thermal comfort applications through several climate conditions.

E3S Web of Conferences ◽

10.1051/e3sconf/202017001007 ◽

2020 ◽

Vol 170 ◽

pp. 01007

Author(s):

Marwa El Yassi ◽

Ikram El Abbassi ◽

Alexandre Pierre ◽

Yannick Melinge

Keyword(s):

Thermal Comfort ◽

Phase Change ◽

Phase Change Material ◽

Phase Change Materials ◽

Chemical Change ◽

Thermal Inertia ◽

Temperature Fluctuations ◽

High Energy ◽

Climate Conditions ◽

Change Material

Nowadays, buildings sector contributes to climate change by consuming a considerable amount of energy to afford thermal comfort for occupants. Passive cooling techniques are a promising solution to increase the thermal inertia of building envelopes, and reduce temperature fluctuations. The phase change materials, known as PCM, can be efficiently employed to this purpose, because of their high energy storage density. Among the various existing solutions, the present study is dedicated to solid-liquid phase change materials. Temperature evolution (according to their defined temperature range) induces the chemical change of the material and its state. For building applications, the chemical transition can be accomplished from liquid to solid (solidification) and from solid to liquid (melting). In fact, this paper presents a comparative thermal analysis of several test rooms with and without phase change materials embedded in a composite wallboard in different climates. The used PCM consist in a flexible sheet of 5 mm thickness (Energain, manufactured by the company DuPont de Nemours). The main properties of such a commercial solution have been delivered by the manufacturer and from analyses. The room model was validated using laboratory instrumentations and measurements of a test room in four cities: Lyon; Reading and Casablanca. Results indicate that this phase change material board can absorb heat gains and also reduce the indoor air temperature fluctuations during daytime. The aim of the study is to show the benefits of this layer with phase change material and compare it in different climatic zones.

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