Phase change materials (PCM) for building envelope applications: A review of numerical models

Phase change materials (PCMs) are increasingly investigated in the last years as successful in many thermal energy storage applications. In the building sector, PCMs are utilised to improve building efficiency by reducing cooling/heating loads and promoting renewable energy sources, such as solar energy. This paper shows the recent research works on integrating PCMs with building envelope for heating purposes. The main PCM categories and their main characteristics are presented, focusing on PCM types applied for building heating applications. The main methods adopted to incorporate PCMs with building elements and materials are mentioned, and the popular passive and active incorporation techniques are discussed. Lastly, the main contribution to building energy saving is discussed in terms of heating applications. The analysed studies indicated that all PCMs could improve the building energy saving in the cold climates by up to 44.16% regardless of their types and techniques. Several conclusions and recommendations are derived from the analysed studies that are believed to be a guideline for further research.

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Experimental Study of the Behavior of Phase Change Materials during Interrupted Phase Change Processes

Energies ◽

10.3390/en14238021 ◽

2021 ◽

Vol 14 (23) ◽

pp. 8021

Author(s):

Rohit Jogineedi ◽

Kaushik Biswas ◽

Som Shrestha

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Numerical Models ◽

Aluminum Foil ◽

Experimental Investigations ◽

Change Processes ◽

Research Article ◽

Thin Aluminum ◽

Phase Change Phenomena ◽

Change Material

This research article explores the behavior of a phase change material (PCM) when it undergoes interrupted melting and freezing, through experimental investigations using a heat flow meter apparatus. A fatty acid-based organic PCM, encapsulated within polyethylene and thin aluminum foil layers, was experimentally tested in this study. Experiments were designed to represent multiple interrupted phase change scenarios that could occur within PCMs applied in buildings. The experimental results were analyzed and compared with previously reported assumptions in numerical models dealing with PCM hysteresis and interrupted phase change processes. These comparisons indicated that the assumptions used in the different numerical models considered can capture the interrupted phase change phenomena with varying degrees of accuracy. The findings also highlighted the need for additional experimental research on different phase change processes that can occur in building applications of PCMs.

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Solar gain mitigation in ventilated tiled roofs by using phase change materials

International Journal of Low-Carbon Technologies ◽

10.1093/ijlct/ctaa001 ◽

2020 ◽

Vol 15 (3) ◽

pp. 434-442

Author(s):

Michele Bottarelli ◽

Francisco Javier González Gallero ◽

Ismael Rodríguez Maestre ◽

Gang Pei ◽

Yuehong Su

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Building Energy ◽

Energy Performance ◽

Building Envelope ◽

Dynamics Model ◽

Night Time ◽

Low Wind Speed ◽

Cooling Design ◽

Hot Season

Abstract Several passive cooling design techniques are known for reducing solar heat gain through building envelope in summer season. These include the use of phase change materials (PCM), which has received an increased attention over the last years, and the strategy of increasing the above-sheathing ventilation (ASV) in ventilated roofs. However, few studies combine both technologies to maximise the building resilience in hot season. The effect of including a PCM layer into a ventilated roof is numerically analysed here in two different configurations: firstly, laid on the roof deck (PCM1 case) and, secondly, suspended in the middle of the ASV channel (PCM2 case). A computational fluid dynamics model was implemented to simulate airflow and heat transfer around and through the building envelope, under 3 days of extreme hot conditions in summer with high temperatures and low wind speed. Results showed slight differences in terms of mean temperatures at the different roof layers, although temperature fluctuations at deck in the PCM1 case were smaller than half of those estimated for the benchmark case. However, PCM2 configuration achieved a daily reduction of about 10 Wh/m2 (18%) in building energy load with respect to the benchmark case, whilst PCM1 got only 4% due to the lower ventilation at night time. Therefore, a suspended PCM layer in the ASV channel would be a better measure in terms of energy performance than laid on the deck surface, although this last option significantly decreases thermal stress of the insulation layer.

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Enhancement of thermal conductivity by graphene as additive in lauric-stearic acid/treated diatomite composite phase change materials for heat storage in building envelope

Energy and Buildings ◽

10.1016/j.enbuild.2021.111087 ◽

2021 ◽

pp. 111087

Author(s):

Weizhun Jin ◽

Linhua Jiang ◽

Lei Chen ◽

Tianjiao Yin ◽

Yue Gu ◽

...

Keyword(s):

Thermal Conductivity ◽

Stearic Acid ◽

Phase Change ◽

Phase Change Materials ◽

Heat Storage ◽

Building Envelope ◽

Composite Phase Change Materials

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Building Envelope with Phase Change Materials

Zero and Net Zero Energy ◽

10.5772/intechopen.85012 ◽

2019 ◽

Cited By ~ 1

Author(s):

Liu Yang ◽

Yan Liu ◽

Yuhao Qiao ◽

Jiang Liu ◽

Mengyuan Wang

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Building Envelope

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Fixed Grid Numerical Models for Solidification and Melting of Phase Change Materials (PCMs)

Applied Sciences ◽

10.3390/app9204334 ◽

2019 ◽

Vol 9 (20) ◽

pp. 4334 ◽

Cited By ~ 6

Author(s):

José Henrique Nazzi Ehms ◽

Rejane De Césaro Oliveski ◽

Luiz Alberto Oliveira Rocha ◽

Cesare Biserni ◽

Massimo Garai

Keyword(s):

Numerical Model ◽

Boundary Conditions ◽

Phase Change ◽

Latent Heat ◽

Phase Change Materials ◽

Source Term ◽

Numerical Models ◽

Fixed Grid ◽

Numerical Studies ◽

The Impact

Phase change materials (PCMs) are classified according to their phase change process, temperature, and composition. The utilization of PCMs lies mainly in the field of solar energy and building applications as well as in industrial processes. The main advantage of such materials is the use of latent heat, which allows the storage of a large amount of thermal energy with small temperature variation, improving the energy efficiency of the system. The study of PCMs using computational fluid dynamics (CFD) is widespread and has been documented in several papers, following the tendency that CFD nowadays tends to become increasingly widespread. Numerical studies of solidification and melting processes use a combination of formulations to describe the physical phenomena related to such processes, these being mainly the latent heat and the velocity transition between the liquid and the solid phases. The methods used to describe the latent heat are divided into three main groups: source term methods (E-STM), enthalpy methods (E-EM), and temperature-transforming models (E-TTM). The description of the velocity transition is, in turn, divided into three main groups: switch-off methods (SOM), source term methods (STM), and variable viscosity methods (VVM). Since a full numerical model uses a combination of at least one of the methods for each phenomenon, several combinations are possible. The main objective of the present paper was to review the numerical approaches used to describe solidification and melting processes in fixed grid models. In the first part of the present review, we focus on the PCM classification and applications, as well as analyze the main features of solidification and melting processes in different container shapes and boundary conditions. Regarding numerical models adopted in phase-change processes, the review is focused on the fixed grid methods used to describe both latent heat and velocity transition between the phases. Additionally, we discuss the most common simplifications and boundary conditions used when studying solidification and melting processes, as well as the impact of such simplifications on computational cost. Afterwards, we compare the combinations of formulations used in numerical studies of solidification and melting processes, concluding that “enthalpy–porosity” is the most widespread numerical model used in PCM studies. Moreover, several combinations of formulations are barely explored. Regarding the simulation performance, we also show a new basic method that can be employed to evaluate the computing performance in transient numerical simulations.

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Reviewing Theoretical and Numerical Models for PCM-embedded Cementitious Composites

Buildings ◽

10.3390/buildings9010003 ◽

2018 ◽

Vol 9 (1) ◽

pp. 3 ◽

Cited By ~ 7

Author(s):

Antonio Caggiano ◽

Christoph Mankel ◽

Eddie Koenders

Keyword(s):

Phase Change ◽

Phase Change Materials ◽

Numerical Models ◽

Grid Method ◽

Cementitious Materials ◽

Research Field ◽

Cementitious Composites ◽

Heat Accumulation ◽

Energy Demands ◽

Theoretical Approaches

Accumulating solar and/or environmental heat in walls of apartment buildings or houses is a way to level-out daily temperature differences and significantly cut back on energy demands. A possible way to achieve this goal is by developing advanced composites that consist of porous cementitious materials with embedded phase change materials (PCMs) that have the potential to accumulate or liberate heat energy during a chemical phase change from liquid to solid, or vice versa. This paper aims to report the current state of art on numerical and theoretical approaches available in the scientific literature for modelling the thermal behavior and heat accumulation/liberation of PCMs employed in cement-based composites. The work focuses on reviewing numerical tools for modelling phase change problems while emphasizing the so-called Stefan problem, or particularly, on the numerical techniques available for solving it. In this research field, it is the fixed grid method that is the most commonly and practically applied approach. After this, a discussion on the modelling procedures available for schematizing cementitious composites with embedded PCMs is reported.

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Energy saving potential of phase change materials-enhanced building envelope considering the six Moroccan climate zones

Journal of Building Physics ◽

10.1177/17442591211006444 ◽

2021 ◽

pp. 174425912110064

Author(s):

Amal Louanate ◽

Rabie El Otmani ◽

Khalid Kandoussi ◽

M’Hamed Boutaous ◽

Daya Abdelmajid

Keyword(s):

Phase Change ◽

Energy Saving ◽

Phase Change Materials ◽

Residential Building ◽

Energy Performance ◽

Building Envelope ◽

Climate Zone ◽

Energy Saving Potential ◽

Heat Penetration ◽

El Jadida

Phase change materials (PCMs) show a good capability in absorbing massive heat when undergoing phase change, which have great potential to be incorporated into building envelopes to enhance indoor thermal comfort by preventing heat penetration into buildings and reducing energy requirements. In this work, a deep analysis of PCM enhanced-walls model has been conducted in six representative climate regions of Morocco: El Jadida, Fez, Marrakesh, Ifrane, and Errachidia. More in detail, numerical simulations were carried out to assess the thermal behavior and energy performance of a residential building integrated with four different PCMs. The results showed that the effectiveness and selection of PCMs strongly depend on local weather where they are applied, characteristics of HVAC systems, PCM layer thickness, and position. Furthermore, with reference to each climate zone, the appropriate PCM leading to the lowest annual energy consumption was identified. The findings show that PCMs are particularly suitable for Mediterranean climates, which a promising annual energy saving of about 41% was obtained. While, the lowest value was recorded in Errachidia city reveals that the integration of PCM has little effect in desert climate zone. As for the other climates considered, values of about 28% to 31% were achieved in the studied house model.

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