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Enhancing supply chain efficiency for air transport of horticultural products by simplified heat and mass transfer modelling
(2026-08-01)
Jantapirak, Suveena
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Duret, Steven
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Laguerre, Onrawee
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Denis, Alain
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Paviet Salomon, Yvanne
Maintaining temperature and quality stability of fresh horticultural products during air transportation is challenging due to highly variable thermal environments and limited airflow inside Unit Load Device (ULD) containers. This study developed a simplified three-dimensional heat and mass transfer model to predict product temperature and moisture evolution within a ULD container under realistic operating conditions. Plaster mangoes were used to avoid the variability of the real product properties. Convective heat transfer and three-directional thermal resistances were integrated into an unsteady heat balance model while the model parameters were calibrated using Monte Carlo simulation. A complementary mass transfer model, considering the ULD container as a closed moisture domain, was implemented to estimate product mass loss. Model performance was evaluated using cooling experiments under controlled conditions and field measurements in a ULD shipment from Bangkok to Paris by air transport. Simulated air and product temperatures showed good agreement with experimental data, with RMSE values below 3.5 °C. The model successfully captured the pronounced thermal load on top-layer boxes during tarmac exposure and the faster cooling of bottom boxes through conduction with the bottom wall during flight. Predicted mass loss (1.0-1.1%) also aligned with field data (1.1-1.2%). The model provides a practical tool for assessing the effects of operational and environmental conditions on fruit quality during air transport.
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Dataset of temperature and relative humidity measurements in domestic refrigerators in Bangkok Thailand
(2026-08-01)
Paviet-Salomon, Yvanne
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Chaomuang, Nattawut
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Potisuwan, Cheeraphat
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Derens-Bertheau, Evelyne
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Nukunudompanich, Methawee
This dataset provides detailed measurements of internal air temperature, product temperature, and relative humidity in domestic refrigerators in households in Bangkok, Thailand. Data were collected from 123 households using Freshliance TagPlus-TH data loggers installed both inside and outside the refrigerators. For each refrigerator, air temperature and relative humidity were monitored at five internal locations: top shelf, middle shelf, vegetable drawer, door shelf, and freezer compartment. In addition, the temperature of a meat-like test product placed on the middle shelf was recorded. Ambient air conditions surrounding each refrigerator were also measured to characterize the external thermal environment. Prior to deployment, all sensors were prepared and activated by the research team, with time zero (T0) defined at this stage. Participants were only required to place the sensors according to the provided instructions while minimizing disturbances to their usual refrigerator usage habits. The sensors remained inside the refrigerators for seven consecutive days, recording measurements every 5 minutes before being removed. Data collected during the first and seventh days of monitoring were excluded from the analysis to account for the uncertainty regarding the exact times at which consumers placed and removed the sensors. This exclusion also helped eliminate transient effects caused by the introduction of heat loads during sensor installation and removal, which are not representative of normal refrigerator operating conditions. Consequently, only the five-day dataset corresponding to stabilized operating conditions is presented. The dataset is provided as tab-delimited.txt files. File names identify both the refrigerator number (1–123) and refrigerator configuration, including single-door, two-door top-freezer, and two-door bottom-freezer models. An accompanying R script enables the generation of temperature and humidity profiles for each refrigerator over the 5-day monitoring period. A README document is also included and provides detailed descriptions of column names, sensor locations, and metadata associated with each measurement campaign. Temperature sensors have a resolution of 0.1°C over a range of −30°C to +70°C, and an expanded uncertainty of ±0.5°C (k = 2). Relative humidity sensors have a resolution of 0.1 % and an expanded uncertainty of ±3 % (k = 2). These uncertainty values are based on the manufacturer’s specifications, additional calibration could not be performed within the scope of this study due to the lack of suitable calibration equipment. This high-resolution dataset provides valuable insights into the thermal and hygrometric conditions of domestic refrigeration systems under real household usage conditions. The data may support a wide range of applications, including the assessment and optimization of refrigeration performance through analysis of temperature heterogeneity and thermal behavior inside refrigerating compartments, the evaluation of food safety and risks associated with domestic storage temperatures, the identification of potential temperature abuse conditions in challenge-test studies, the development of consumer recommendations, the development and validation of simplified thermal models and CFD simulations for predicting airflow and heat transfer within domestic refrigerators, studies related to energy consumption and food preservation, and the optimization of domestic refrigerator design parameters using CFD and artificial neural network approaches. The dataset is expected to provide valuable insights for researchers, stakeholders, and policymakers working on refrigeration technologies, food safety, and cold-chain management.
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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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Storage conditions, energy consumption, and food safety implications of domestic refrigerators in Bangkok
(2025-12-01)
Chaomuang, Nattawut
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Potisuwan, Cheeraphat
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Duret, Steven
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Derens-Bertheau, Evelyne
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Paviet-Salomon, Yvanne
Domestic refrigeration plays a critical role in food preservation and safety by maintaining optimal storage conditions for perishable items. This study investigated the temperature and humidity conditions, as well as the energy consumption, of domestic refrigerators in Bangkok. Data were collected through on-site investigations of 123 refrigerators using data loggers to record temperature, humidity, and electrical consumption over a five-day period. In addition, a predictive microbiological model was used to assess the potential for microbial growth under the investigated storage conditions, specifically of Listeria monocytogenes and lactic acid bacteria (LAB). Results indicated that although the overall mean temperatures of chilling compartments (5.0 ± 2.5 °C) were within the recommended range for domestic refrigeration, only about 30–40 % of individual refrigerators consistently maintained temperatures at or below 5 °C on the top and middle shelves throughout the five-day monitoring period, where fresh and ready-to-eat products are typically stored. Electrical consumption analysis revealed significant differences across refrigerator types; appliances with two doors and bottom freezers exhibited the highest annual electrical consumption, while single door refrigerators recorded the lowest. However, the specific energy consumption (SEC) did not differ significantly among refrigerator types. The microbial exposure assessment based on a test product highlighted that for over 50 % of refrigerators, L. monocytogenes load exceeds the regulation safety limits (> 102 CFU/g) within five days. These findings emphasize the need for improved temperature control, appliance design, and consumer education to ensure food safety and energy efficiency in domestic refrigeration.
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Evaporative cooling with a wet fabric blanket for non-refrigerated horticultural produce transport: An experimental study
(2024-12-01)
Chaomuang, Nattawut
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Laguerre, Onrawee
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Supapvanich, Suriyan
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Flick, Denis
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Duret, Steven
Due to the high cost of mechanical refrigeration, Evaporative Cooling (EC) can be an alternative technology for small farmers in developing countries, such as Thailand. This study aimed to experimentally investigate the performance of EC using a wet fabric blanket. A real-scale cargo chamber, commonly used in Thailand, was constructed, and equipped with axial fans to simulate airflow during transportation. Two pallets of test products (hollow plastic balls) were loaded into the cargo and covered with the wet blanket. During the experiment, the inlet air velocities varied from 0.8 m s−1 to 3.6 m s−1 while the constant climate conditions were maintained (29–30 °C and 70–73 %RH). The air and product temperatures and air relative humidity were measured every minute for 3 h using thermocouples and hygrometers, respectively. The proposed EC method allowed the air temperature to decrease by approximately 3–4 °C. When the inlet air velocity decreased, a lower temperature reduction was observed. Simplified heat and mass transfer models were developed to interpret the load temperature evolution from the inlet to the outlet positions at different air velocities. The comparison between the measured and calculated data revealed a maximum mean relative error of 1.2 %. The quality preservation performance was also evaluated based on lettuce mass loss. Lower mass loss was observed for the product stored inside the cargo chamber (<6 %) compared to those outside (8–10 %). This study suggests the potential use of a wet blanket as an EC cooling medium for a short-distance transport to enhance the cold chain performance in Thailand.
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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 107. 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−1, 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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Temperature control in a horticultural produce supply chain in Thailand and its influence on product quality
(2022-03-01)
Chaomuang, Nattawut
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Singphithak, Parinya
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Laguerre, Onrawee
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Suwapanich, Rachit
The present study was conducted in order to investigate the temperature conditions in the horticultural produce cold chain in Thailand, and fresh-cut baby corn was chosen for a case study. The field investigation together with in-person interviews were performed at 4 growers' premises and one packing house. The information collected provided details on current postharvest conditions at individual stages from the growers’ premises to an export distribution center. Temperature measurements were carried out to explore the time-temperature profiles throughout these stages. The results showed that the total duration of these stages was almost 32 h, and the temperature variations were between 6 and 33 °C. Precooling was delayed for at least 9 h, since baby corn cobs were primarily processed by dehusking and bulk packing. The baby corn was maintained at a temperature below 6.0 °C in a cold room for almost half of the total duration. The effect of the postharvest temperature conditions on the product quality evaluation was assessed by measuring various physiological quality attributes during storage. It was found that the marketability of the baby corn subjected to such postharvest temperature conditions remained possible with a salable period of up to two weeks. The result made it possible to identify the stages during which temperature control was inadequate, and recommendations were proposed to the stakeholder partner in order to modify the postharvest conditions in order to extend the product shelf life.

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