Numerical Investigation and Nondimensional Analysis of the Dynamic Performance of a Thermal Energy Storage System Containing Phase Change Materials and Liquid Water

2016 ◽  
Vol 139 (2) ◽  
Author(s):  
Hebat-Allah M. Teamah ◽  
Marilyn F. Lightstone ◽  
James S. Cotton
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Phase Change Materials ◽  
Storage Capacity ◽  
Dynamic Performance ◽  
Water System ◽  
Heat Transfer Fluid ◽  
Energy Storage Capacity

The dynamic performance of a thermal energy storage tank containing phase change material (PCM) cylinders is investigated computationally. Water flowing along the length of the cylinders is used as the heat transfer fluid. A numerical model based on the enthalpy-porosity method is developed and validated against experimental data from the literature. The performance of this hybrid PCM/water system was assessed based on the gain in energy storage capacity compared to a sensible only system. Gains can reach as high as 179% by using 50% packing ratio and 10 °C operating temperature range in water tanks. Gains are highly affected by the choice of PCM module diameter; they are almost halved as diameter increases four times. They are also affected by the mass flow rate nonlinearly. A nondimensional analysis of the energy storage capacity gains as a function of the key nondimensional parameters (Stefan, Fourier, and Reynolds numbers) as well as PCM melting temperature was performed. The simulations covered ranges of 0.1 <  Stẽ  < 0.4, 0 < Fo < 600, 20 < Re < 4000, 0.2<(ρCP)*<0.8, and 0.2<θm<0.8.

scholarly journals Using the Analytic Hierarchy Process to Prioritize and Select Phase Change Materials for Comfort Application in Buildings

2014 ◽  
Vol 10 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Lavinia Gabriela Socaciu ◽  
Paula Veronica Unguresan
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Phase Change Materials ◽  
Storage Capacity ◽  
Heat Storage ◽  
Analytic Hierarchy ◽  
Energy Storage Capacity ◽  
Hierarchy Process

Abstract Phase change materials (PCMs) selection and prioritization for comfort application in buildings have a significant contribution to the improvement of latent heat storage systems. PCMs have a relatively large thermal energy storage capacity in a temperature range close to their switch point. PCMs absorb energy during the heating process as phase change takes place and release energy to the environment in the phase change range during a reverse cooling process. Thermal energy storage systems using PCMs as storage medium offer advantages such as: high heat storage capacity and store/release thermal energy at a nearly constant temperature, relative low weight, small unit size and isothermal behaviour during charging and discharging when compared to the sensible thermal energy storage. PCMs are valuable only in the range of temperature close to their phase change point, since their main thermal energy storage capacity depend on their mass and on their latent heat of fusion. Selection of the proper PCMs is a challenging task because there are lots of different materials with different characteristics. In this research paper the principles and techniques of the Analytic Hierarchy Process (AHP) are presented, discussed and applied in order to prioritize and select the proper PCMs for comfort application in buildings. The AHP method is used for solving complex decisional problems and allows the decision maker to take the most suitable decisions for the problem studied. The results obtained reveal that the AHP method can be successfully applied when we want to choose a PCM for comfort application in buildings.

A facile one-step synthesis of porous N-doped carbon from MOF for efficient thermal energy storage capacity of shape-stabilized phase change materials

2019 ◽  
Vol 12 ◽  
pp. 239-249 ◽  
Author(s):  
Dimberu G. Atinafu ◽  
Wenjun Dong ◽  
Changmin Hou ◽  
Radoelizo S. Andriamitantsoa ◽  
Jingjing Wang ◽  
...  
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Phase Change Materials ◽  
Storage Capacity ◽  
Energy Storage Capacity ◽  
One Step

Experimental Investigation on a PCM Based Thermal Energy Storage System for a VCR System

2021 ◽  
Vol 106 ◽  
pp. 116-120
Author(s):  
Shaik Riyaz Basha
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Phase Change Material ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Cycle Time ◽  
Phase Change Materials ◽  
Storage Capacity ◽  
Food Storage ◽  
Change Material

Thermal energy storage (TES) based on hidden heat concept is good substitute for sensible heat storage because of its dense storage capacity and almost constant temperature heat transfers during the charging and discharging cycle. During no load and low cooling load conditions the system stores the thermal energy in the storage medium (phase change material) which will be used latter to meet the requirement in off cycle conditions. The intention of present work is to increase the system off cycle time, maintain required temperatures during power cuts by joining a few inch thick layer of phase change material on the outer surface of the evaporator. For investigation purpose a deep freezer which runs on vapor compression system of 50 liters storage capacity is fabricated with and without phase change materials. The eutectic compositions nearly 23 wt% salt (NaCl) dissolved in water and aluminium nitrate around 26 wt% dissolved in water are used as phase change materials. By the end of all experimental investigations it was noticed that the off cycle time system with phase change material is increased by 5.5 hours compared to system without phase change material, food storage time is enhanced by 8 to 14 hrs and a little power saving also achieved.

Thermal Conductivity of Paraffin Wax as Microencapsulated Phase Change Material (PCM) Coated on Polyester Fabric

2015 ◽  
Vol 1134 ◽  
pp. 160-164 ◽  
Author(s):  
Abu Bakar Mahamad Dom ◽  
Najua Tulos ◽  
Wan Yunus Wan Ahmad ◽  
Ahmad Faiza Mohd ◽  
Mohamad Faizul Yahya
Keyword(s):  
Thermal Conductivity ◽  
Energy Storage ◽  
Phase Change ◽  
Phase Change Material ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Storage Capacity ◽  
Microencapsulated Phase Change Material ◽  
Energy Storage Capacity ◽  
Change Material

This research works involves the production of microencapsulated phase change material (PCM) in which paraffin wax was used as the core components with sebacyol chloride (SC) and hexamathylene diamine (HMD) as the shell component. The microencapsulated PCM was characterized using Fourier Transform Infrared (FTIR) and scanning electron microscopy (SEM). Thermal energy storage capacity was measured by differential scanning calorimetry (DSC) while thermal conductivity was measured by thermal gravimetric analysis (TGA). The microencapsulated PCM were found to have a regular spherical shape with a size of 50µm while FTIR indicated that the microencapsulation process occurs due to the existence of alkyl group (C-H) and carbonyl group (C=O) in the spectra. DSC analysis shows that the paraffin start to melt at 47°C to 56°C with thermal energy storage capacity of 140.097 J/g and 114.766 J/g for sample A and sample B respectively. It was found that higher value of thermal energy storage resulting to lower thermal conductivity, which can be used as a thermal barrier in various applications.

Numerical and Experimental Investigation of Shell-and-Tube Phase-Change Material Thermal Energy Storage Unit

2016 ◽  
Vol 138 (3) ◽  
Author(s):  
Thomas H. Sherer ◽  
Yogendra Joshi
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Phase Change Materials ◽  
Control Volume ◽  
Heat Transfer Fluid ◽  
Transient Temperature ◽  
Storage Unit ◽  
Shell And Tube

Solid liquid phase-change materials (PCMs) present a promising approach for reducing data center cooling costs. We review prior research in this area. A shell-and-tube PCM thermal energy storage (TES) unit is then analyzed numerically and experimentally. The tube bank is filled with commercial paraffin RUBITHERM RT 28 HC PCM, which melts as the heat transfer fluid (HTF) flows across the tubes. A fully implicit one-dimensional control volume formulation that utilizes the enthalpy method for phase change has been developed to determine the transient temperature distributions in both the PCM and the tubes themselves. The energy gained by a column of tubes is used to determine the exit bulk HTF temperature from that column, ultimately leading to an exit HTF temperature from the TES unit. This paper presents a comparison of the numerical and experimental results for the transient temperature profiles of the PCM-filled tubes and HTF.

scholarly journals Investigation of the dynamic characteristics of a thermal energy storage unit filled with multiple phase change materials

2018 ◽  
Vol 22 (Suppl. 2) ◽  
pp. 527-533 ◽  
Author(s):  
Xiaoyan Li ◽  
Rongpeng Huang ◽  
Xinyue Miao ◽  
Xuelei Wang ◽  
Yabin Liu ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Energy Storage ◽  
Phase Change ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Phase Change Materials ◽  
Storage Systems ◽  
Heat Transfer Fluid ◽  
Energy Storage Systems ◽  
Thermal Energy Storage Systems

In order to improve the thermal performance of thermal energy storage systems, a packed bed thermal energy storage systems unit using spherical capsules filled with multiple phase change materials (multi-PCM) for use in conventional air-conditioning systems is presented. A 3-D mathematical model was established to investigate the charging characteristics of the thermal energy storage systems unit. The optimum proportion between the multi-PCM was identified. The effects of heat transfer fluid-flow rate and heat transfer fluid inlet temperature on the liquid phase change materials volume fraction, charging time and charging capacity of the thermal energy storage system unit are studied. The results indicate that the charging capacity of multi-PCM units is higher than that of the conventional single-PCM (HY-2). For proportions 0:1:0, 2:3:3, 3:2:3, 3:3:2, 4:1:3, and 4:2:2, the charging capacity decreases by approximately 24.84%, 14.69%, 6.47%, 3.82%, and 1.13%, respectively, compared to the 4:2:2 proportion. Moreover, decreasing the heat transfer fluid inlet temperature can obviously shorten the complete charging time of the thermal energy storage systems unit.

Natural microtubule encapsulated phase change material with high thermal energy storage capacity

Energy ◽  
2019 ◽  
Vol 172 ◽  
pp. 1144-1150 ◽  
Author(s):  
Shaokun Song ◽  
Tingting Zhao ◽  
Feng Qiu ◽  
Wanting Zhu ◽  
Taorui Chen ◽  
...  
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Phase Change Material ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Storage Capacity ◽  
Energy Storage Capacity ◽  
Encapsulated Phase Change Material ◽  
Change Material
Sign in / Sign up

Export Citation Format

Share Document