Latent heat thermal energy storage (LHTES) uses phase change materials (PCMs) to store and release heat, and can effectively address the mismatch between energy supply and demand. However, it suffers from low thermal conductivity and the leakage problem. One of the solutions is integrating porous supports and PCMs to fabricate shape-stabilized phase change materials (ss-PCMs). The phase change heat transfer in porous ss-PCMs is of fundamental importance for determining thermal-fluidic behaviours and evaluating LHTES system performance. This paper reviews the recent experimental and numerical investigations on phase change heat transfer in porous ss-PCMs. Materials, methods, apparatuses and significant outcomes are included in the section of experimental studies and it is found that paraffin and metal foam are the most used PCM and porous support respectively in the current researches. Numerical advances are reviewed from the aspect of different simulation methods. Compared to representative elementary volume (REV)-scale simulation, the pore-scale simulation can provide extra flow and heat transfer characteristics in pores, exhibiting great potential for the simulation of mesoporous, microporous and hierarchical porous materials. Moreover, there exists a research gap between phase change heat transfer and material preparation. Finally, this review outlooks the future research topics of phase change heat transfer in porous ss-PCMs.

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A review of phase change heat transfer in shape-stabilized phase change materials (ss-PCMs) based on porous supports for thermal energy storage

Characterization and Simulation of Microstructure and Properties of EPS Lightweight Concrete

Wood waste as an alternative thermal insulation for buildings

Experimental determination and fractal modeling of the effective thermal conductivity of autoclaved aerated concrete: Effects of moisture content

Heat transfer—A review of 2003 literature

Transient melting of paraffin waxes embedded in aluminum foams: Experimental results and modeling

This paper explores the possible use of R1234yf and R1234ze(E) during condensation inside a microfin tube with an inner diameter at the fin tip of 2.4 mm as replacement of R134a. Having thermodynamic properties close to those of R134a, R1234yf and R1234ze(E) are some of its possible replacements for air conditioning and refrigeration systems. Experimental tests were carried out for mass velocities from 300 to 1000 kg m−2 s−1, vapor qualities from 0.95 to 0.2, at saturation temperatures of 30 °C and 40 °C. From the experimental measurements, it has been possible to calculate the heat transfer coefficient and to measure the frictional pressure drop. Globally speaking, R1234ze(E) shows heat transfer coefficients similar to those of R134a, whereas R1234yf shows slightly lower values. R1234ze(E) frictional pressure drops are some 30% higher than those of R134a, whereas R1234yf shows values similar to R134a. The experimental results of heat transfer coefficient and frictional pressure drop were also compared against values predicted by empirical correlations.

Low GWP refrigerants condensation inside a 2.4 mm ID microfin tube

Experimental study on heat transfer condensation of R1234ze(E) and R134a inside a 4.0 mm OD horizontal microfin tube

The purpose of this work was to study both theoretically and experimentally the process of moisture redistribution and heat transfer due to phase changes during the tests of thermal conductivity in aerated autoclaved concrete (AAC) moist specimens. The different moisture contents of the test samples were obtained in climatic chamber at equilibrium conditions reached with constant air temperature and variable relative humidity. The moist specimens were sealed inside highly impermeable polyethylene bag, as required by UNI 10051, and placed in a heat flow meter apparatus. During the experimental thermal conductivity measurements, the temperature and heat flow rate were measured under transient and steady state conditions. A theoretical analysis of the heat and mass transfer process was performed and then a suitable numerical model was used to predict the moisture redistribution and heat transfer due to the phase changes. The theoretical model has been compared against the experimental data. Substantial agreement between numerical results and experimental data was found. Then several numerical simulations have been performed to study the influence of the errors due to phase changes and non-uniform moisture distribution during the test of thermal conductivity of moist AAC specimens.

Effect of Moisture Movement on Tested Thermal Conductivity of Moist Aerated Autoclaved Concrete

It is well known that the thermal performance of some insulating and building materials is related to the actual operating conditions because the thermal conductivity of such materials is highly dependent on the moisture content. Since the thermal conductivity of liquid water is about 25 times greater than that of air, it is quite easy to understand how even small variations of the moisture content can have a significant impact on thermal performance. For this reason it is important to find a correlation between the moisture content in a specimen and its thermal conductivity. The purpose of this paper is to investigate both experimentally and theoretically the moisture contribution during the measurement of the heat transfer properties in light concrete slabs (autoclaved concrete and concrete lighted with polystyrene pearls) and to correlate its thermal transmissivity with the moisture content.

Manuela Campanale

Papers

Transient melting of paraffin waxes embedded in aluminum foams: Experimental results and modeling

Low GWP refrigerants condensation inside a 2.4 mm ID microfin tube

Experimental study on heat transfer condensation of R1234ze(E) and R134a inside a 4.0 mm OD horizontal microfin tube

Effect of Moisture Movement on Tested Thermal Conductivity of Moist Aerated Autoclaved Concrete

Analytical and Experimental Investigations on the Heat Transfer Properties of Light Concrete