Early Age Temperature Control in Mass Concrete Through Incorporation of Dispersed Phase Change Materials (PCMs)

2021 ◽  
pp. 13-24
Author(s):  
Mohammad Kheradmand ◽  
Romeu Vicente ◽  
Miguel Azenha ◽  
José Luís Barroso de Aguiar
Keyword(s):  
Phase Change ◽  
Temperature Control ◽  
Phase Change Materials ◽  
Dispersed Phase ◽  
Early Age ◽  
Mass Concrete

scholarly journals Energy Saving and Charging Discharging Characteristics of Multiple PCMs Subjected to Internal Air Flow

Fluids ◽  
2021 ◽  
Vol 6 (8) ◽  
pp. 275
Author(s):  
Ahmed J. Hamad
Keyword(s):  
Phase Change ◽  
Energy Saving ◽  
Air Temperature ◽  
Temperature Control ◽  
Phase Change Materials ◽  
Energy Savings ◽  
Heating System ◽  
Air Heating ◽  
Room Model ◽  
Model Temperature

One essential utilization of phase change materials as energy storage materials is energy saving and temperature control in air conditioning and indirect solar air drying systems. This study presents an experimental investigation evaluating the characteristics and energy savings of multiple phase change materials subjected to internal flow in an air heating system during charging and discharging cycles. The experimental tests were conducted using a test rig consisting of two main parts, an air supply duct and a room model equipped with phase change materials (PCMs) placed in rectangular aluminum panels. Analysis of the results was based on three test cases: PCM1 (Paraffin wax) placed in the air duct was used alone in the first case; PCM2 (RT–42) placed in the room model was used alone in the second case; and in the third case, the two PCMs (PCM1 and PCM2) were used at the same time. The results revealed a significant improvement in the energy savings and room model temperature control for the air heating system incorporated with multiple PCMs compared with that of a single PCM. Complete melting during the charging cycle occurred at temperatures in the range of 57–60 °C for PCM1 and 38–43 °C for PCM2, respectively, thereby validating the reported PCMs’ melting–solidification results. Multiple PCMs maintained the room air temperature at the desired range of 35–45.2 °C in the air heating applications by minimizing the air temperature fluctuations. The augmentation in discharging time and improvement in the room model temperature using multiple PCMs were about 28.4% higher than those without the use of PCMs. The total energy saving using two PCMs was higher by about 29.5% and 46.7% compared with the use of PCM1 and PCM2, respectively. It can be concluded that multiple PCMs have revealed higher energy savings and thermal stability for the air heating system considered in the current study.

Analysis of Passive Temperature Control Systems Using Phase Change Materials for Application to Secondary Batteries Cooling

2018 ◽  
Vol 10 (6) ◽  
Author(s):  
Roberto Bubbico ◽  
Francesco D'Annibale ◽  
Barbara Mazzarotta ◽  
Carla Menale
Keyword(s):  
Thermal Conductivity ◽  
Phase Change ◽  
Temperature Control ◽  
Phase Change Materials ◽  
Heat Fluxes ◽  
Battery Thermal Management ◽  
Thermal Management System ◽  
Battery Thermal Management System ◽  
Safe Limits ◽  
Computational Fluid Dynamics Cfd

Abstract Temperature control is one of the most significant factors to improve the performance and extend the cycle life of a battery. It is, therefore, important to design and implement an effective battery thermal management system (TMS). Phase change materials (PCMs) can be used as a cooling means for batteries. In the present paper, a preliminary analysis of the thermal behavior of PCMs used to cool down a heated metal surface was carried out. Tests have shown that pure PCMs are able to limit the temperature increase, but only for relatively low-heat fluxes. At higher values of the heat produced, the thermal conductivity of the PCM was increased by using solid foams characterized by higher thermal conductivity; it was, thus, possible to keep the surface temperature within safe limits for longer times. A computational fluid dynamics (CFD) model of the composite material (PCM + solid foam) was also developed, which allowed to predict the temperature trend within the system under different boundary conditions. However, the average thermal conductivity of the composite system that best fitted the experimental results was found to be much lower than that theoretically predicted by using common semiempirical correlations.

scholarly journals Feasibility of Using Phase Change Materials to Control the Heat of Hydration in Massive Concrete Structures

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Won-Chang Choi ◽  
Bae-Soo Khil ◽  
Young-Seok Chae ◽  
Qi-Bo Liang ◽  
Hyun-Do Yun
Keyword(s):  
Phase Change ◽  
Latent Heat ◽  
Phase Change Materials ◽  
Cement Mortar ◽  
Concrete Structures ◽  
Experimental Tests ◽  
Heat Of Hydration ◽  
Hydration Heat ◽  
Experimental Results ◽  
Mass Concrete

This paper presents experimental results that can be applied to select a possible phase change material (PCM), such as a latent heat material (LHM), to control the hydration heat in mass concrete structures. Five experimental tests (microconduction, simplified adiabatic temperature rise, heat, and compressive strength tests) were conducted to select the most desirable LHM out of seven types of inorganic PCM used in cement mortar and to determine the most suitable mix design. The results of these experimental tests were used to assess the feasibility of using PCM to reduce hydration heat in mass concrete that was examined. The experimental results show that cement mortar containing barium- [Ba(OH)2·8H2O] based PCM has the lowest amount of total hydration heat of the cement pastes. The barium-based PCM provides good latent heat properties that help to prevent volume change and microcracks caused by thermal stress in mass concrete.

Thermal energy storage property and temperature control performance of phase change materials eutectic mixture nanocomposite

2021 ◽  
Vol 13 ◽  
Author(s):  
Seyed Mostapha Musavi ◽  
Ghodratollah Roudini ◽  
Farahnaz Barahuie ◽  
Siti Ujila Binti Masuri
Keyword(s):  
Stearic Acid ◽  
Thermal Cycling ◽  
Phase Change ◽  
Temperature Control ◽  
Thermal Energy ◽  
Phase Change Materials ◽  
Eutectic Mixture ◽  
Impregnation Method ◽  
Control Performance ◽  
Test Room

Background: The utilization of high-performance phase change materials (PCMs) that can reversibly store thermal energy is of immense interest and strategy for effective energy conservation and management. Methods: In this work, a new PCM nanocomposite, consisting of a eutectic mixture of stearic acid and n-nonadecane as core and SiO2 as shell, was prepared by direct impregnation method. Additionally, a laboratory scaled test room was designed to investigate the intelligent temperature control function of the nanocomposite in building materials. Results: The optimized nanocomposite was characterized using Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM) techniques. The DSC data demonstrated that the PCMs eutectic mixture content in the stearic acid- n-nonadecane–SiO2 nanocomposite was 52.8 wt.% and the melting temperatures and latent heats of stearic acid - n-nonadecane eutectic mixture and optimized nanocomposite were 45.1 and 44.0 °C, and 163.7 and 86.5 J/g, respectively. Furthermore, the accelerated thermal cycling test confirmed the excellent thermal cycling stability of the nanocomposite after 500 heating-cooling cycles. Moreover, the laboratory scaled test room results showed that the incorporation of the resulting nanocomposite in the gypsum could reduce indoor temperature fluctuation, and the performance was improved with the increase in the mass percentage of the nanocomposite in the gypsum composite. Conclusion: The obtained nanocomposite had good thermal reliability and temperature control performance and thus can be a promising candidate for hi-tech applications in intelligent temperature control and precise thermal management.

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