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Development and thermal performance of a portable solar cooker using glycerol-erythritol phase change material
(2026-07-01)
Pinnarat, Tanawan
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Tetthong, Areena
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Chaumsuk, Benya
This study presents a portable and thermally efficient solar cooking system that employs a 25 wt% glycerol-erythritol mixture as phase change material (PCM) for thermal energy storage. The solar cooker utilizes a box-type solar collector to absorb solar radiation and store energy in the PCM. A two-dimensional transient heat transfer model was developed to analyze temperature profiles during cooking. The simulation results showed good agreement with laboratory experimental data and guided the design of a solar cooker capable of preparing meals for two people. Because erythritol's relatively high melting point limits its ability to fully absorb solar energy under typical solar radiation, glycerol was introduced to reduce the melting point. A prototype solar rice cooker accommodating two servings was fabricated and tested under three conditions: (i) direct solar energy without PCM, (ii) sun-exposed pre-melted 25 wt% glycerol-erythritol PCM with non-solar cooking, and (iii) sun-exposed pre-melted 25 wt% glycerol-erythritol PCM with solar cooking. MATLAB simulations were used to model transient heat transfer and temperature distribution during cooking. Experimental results indicated that condition 3 was the most effective cooking method. Under condition 1, rice was fully cooked in approximately 240 minutes, while condition 2 produced undercooked rice due to incomplete PCM melting. Overall, this study demonstrates the feasibility of integrating PCM with solar energy to improve cooking efficiency, contributing to the advancement of sustainable, off-grid cooking technologies.
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Thermal performance evaluation of water-based gel packs and insulating covers: A case study on raw milk preservation for local transport
(2025-12-01)
Chaomuang, Nattawut
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Laguerre, Onrawee
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Flick, Denis
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Duret, Steven
Maintaining the quality and safety of raw milk during transportation to collection centers poses significant challenges for small-scale producers, especially in regions with limited access to advanced refrigeration systems. This study proposes a cost-effective cooling system utilizing water-based phase change material (PCM) gel packs and UV-reflective covers. The thermal performance was evaluated using a tank filled with water, both with and without PCM, under constant and variable ambient temperature conditions. Results demonstrated that the tanks with PCM achieved a temperature reduction of 10–13 °C within an hour. Comparative analysis revealed similar thermal behaviors for milk and water, enabling the extrapolation of results. A simplified heat transfer model based on energy balance was developed to predict product temperature changes under different operational conditions. Some input parameters were adjusted using experimental data, and the model was subsequently validated against separate experimental datasets, showing reasonable accuracy (RMSE < 3.0 °C). The model could be used for application under comparable conditions. Furthermore, milk quality preservation was assessed through the enumeration of Escherichia coli and total coliforms in milk stored in tanks with and without PCM, as well as through predictive microbiological modeling. Both measured and predicted results suggested a moderate reduction in E. coli growth rates (1.1–1.3 times slower) in the tank with PCM, depending on initial microbial load. Based on these findings, the proposed system offers an effective and economical solution for small milk producers, enhancing cold-chain management and reducing spoilage.
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Dataset of air velocity and temperature fields inside an insulated box equipped with phase change material under several operating conditions
(2024-02-01)
Leungtongkum, Tanathep
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Flick, Denis
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Chaomuang, Nattawut
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Denis, Alain
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Laguerre, Onrawee
This article contains a description of protocol to measure air velocity field (by Particle Image Velocimetry - PIV) and temperature field (by T-type thermocouples) in an insulated box equipped with Phase Change Material (PCM) of melting point 0 °C. The influence of various conditions was studied: i) PCM position (at sidewall and at top), ii) aspect ratio of the box (height/width ∼ 1 and 1.7), iii) ambient temperature (10 °C, 20 °C and 30 °C), iv) test product initial temperature (4 °C and 10 °C) and vi) spacing beneath the load (0 mm and 20 mm). This article is related to a published research paper, it provides the dataset of all experiments which can be useful for experimenter to understand the phenomena and for expert in numerical model to validate the developed model e.g., by Computational Fluid Dynamic.
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Influence of use conditions on heat transfer in an insulated box equipped with a phase change material
(2023-11-01)
Leungtongkum, Tanathep
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Flick, Denis
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Chaomuang, Nattawut
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Denis, Alain
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Laguerre, Onrawee
An insulated box with Phase Change Material (PCM – ice, melting point ∼ 0 °C) and loaded by test product (Tylose) was investigated experimentally to study the effect of the PCM position, Aspect Ratio (AR = height/width) of box, ambient temperature, initial test product temperature and spacing beneath the test product. The temperature and the air velocity measured by thermocouples and Particle Image Velocimetry (PIV), respectively, were analyzed under stable conditions. The maximum product temperature was lower for PCM at the top (6.6 °C, AR ≈ 1) than for PCM on a sidewall (7.7 °C, AR ≈ 1) and increased with AR (9.9 °C, AR ≈ 1.7). A non-linear relation between ambient temperature and product temperature was observed with the maximum product temperature from 5.2 °C (10 °C ambient) to 9.1 °C (30 °C ambient). The influence of spacing beneath the product was negligible despite different airflow patterns. Simple equations were proposed to predict the maximum storage time and mean temperature in the box enabling us to study the influence of PCM and product mass, melting point, box insulation and ambient temperature.
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Experimental investigation of airflow and heat transfer by natural convection in an insulated box with a Phase Change Material using a Particle Image Velocimetry technique
(2023-01-01)
Leungtongkum, Tanathep
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Laguerre, Onrawee
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Flick, Denis
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Denis, Alain
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Duret, Steven
Airflow and heat transfer via natural convection in an insulated box with Phase Change Material (PCM) were experimentally investigated using Particle Image Velocimetry (PIV) and temperature measurements. The effects of PCM positions (side wall and lid) on flow pattern and temperature distribution were studied under empty and loaded conditions. Two loads were considered to study the obstacle effect and the influence of heat exchange with air. When PCM was either at the side wall or at the lid of the box, laminar flow was observed and the corresponding Rayleigh number was about 10<sup>7</sup>. Upward flow was always observed near the side walls of the box. When PCM was on the side, downward flow occurred along the PCM; in the empty case, flow was almost 2D but became 3D when the load was added. When PCM was on the lid, the air cooled in contact with PCM, detached from it and flowed downwards. In the empty case, downward flow was unstable, and with the load, it followed preferential pathways. The type of load exerted little effect on flow patterns at thermal steady state. Thus, a simpler load (extruded polystyrene) can be used in the first approach. The maximum velocity was about 0.1 m s<sup>−1</sup>, so free convection cannot be neglected compared with conduction. Regarding temperature performance, PCM on the side and on the lid showed no substantial difference if gaps were left between the load and the walls or PCM.
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Dataset of experimental study investigation of airflow and heat transfer in an insulated box equipped with a phase change material
(2022-12-01)
Leungtongkum, Tanathep
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Laguerre, Onrawee
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Flick, Denis
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Denis, Alain
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Duret, Steven
This article contains a detailed description of the experimental protocol of air velocity (by particle image velocimetry - PIV) and temperature measurement (by T-type thermocouples) in an insulated box equipped with a Phase Change Material (PCM). The study was conducted in an empty box and a loaded box with extruded polystyrene slabs (XPS) and methylcellulose slabs (test product). The measurement was conducted at the middle plane and lateral plane. This article contains a complete dataset along with the illustrated figures of conducted experiment. They lead to more understanding of phenomena inside a closed cavity with a cold source and can be useful for validating numerical models, e.g., the results computed by computational fluid dynamic.

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