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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
;
Denis, Alain
;
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
;
Flick, Denis
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Chaomuang, Nattawut
;
Denis, Alain
;
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
;
Denis, Alain
;
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
;
Laguerre, Onrawee
;
Flick, Denis
;
Denis, Alain
;
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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A simplified heat transfer model of a closed refrigerated display cabinet
(2020-06-01)
Chaomuang, Nattawut
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Laguerre, Onrawee
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Flick, Denis
Installation of doors on open refrigerated display cabinets is one of the simple and effective methods to improve the cabinet performance because it can reduce the warm and humid air infiltration into the cabinets. However, the presence of doors can change airflow pattern, which in turn influences the heat transfer and product temperatures. It is, thus, necessary to understand these thermal phenomena. This study proposes a simplified heat transfer model developed based on a zonal approach to describe the evolution of air and product temperatures at different zones in the closed refrigerated display cabinet. For model validation, the predicted values were compared with measured air and load temperatures for three external air temperatures. Good agreement was found between the predicted and measured temperatures with the maximum difference of less than 0.5 °C for every studied position and the overall mean absolute error of 0.2 °C. The model was then used to predict the effect of the air infiltration through the door gaps on the performance of the closed display cabinet in both thermal and energy aspects. This developed model will be further used in the modeling of the cold chain, where several types of refrigeration equipment are used to keep products under low-temperature conditions from production to consumption. Through integration of quality and microbiological predictive models, this approach can be used as a numerical tool for an evaluation tool for consumer risk.
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Dynamic heat transfer modeling of a closed refrigerated display cabinet
(2019-10-01)
Chaomuang, Nattawut
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Laguerre, Onrawee
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Flick, Denis
This study proposes a simplified heat transfer model of a closed refrigerated display cabinet using a zonal approach. The dynamic model was developed and solved with a spectral method to predict the temperature fluctuations occurring with “on/off” compressor regulation. The equivalent load thickness in which the temperature fluctuations were of the same order as those at the load surface was estimated as a function of “on/off” compressor operating frequency. The air temperature fluctuations are dampened whenever the air exchanges heat with solid surfaces (e.g. walls, loads) and with the ambient air (e.g. through the doors). Despite exposure to large air temperature fluctuations (up to 5 °C), the load surface temperature showed only small fluctuations (ΔT<inf>l</inf> ≤ 0.5 °C). Good agreement was found between the predicted and the measured temperature fluctuations. The model can also be applied in order to predict air and load temperature increases during defrost operation.
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Experimental analysis of heat transfer and airflow in a closed refrigerated display cabinet
(2019-03-01)
Chaomuang, Nattawut
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Flick, Denis
;
Denis, Alain
;
Laguerre, Onrawee
This study presents the experimental investigations on heat transfer and airflow in a closed refrigerated display cabinet. Air and product temperatures and air velocity were measured with thermocouples and a hot-wire anemometer, respectively. Temperature variation in the cabinet depends on the positions. The front areas contributed to higher temperature, whereas the rear areas were at a lower temperature. Benefits of doors were also examined by comparing the results of air and product temperatures with the case without doors. The cabinet with doors provided less temperature heterogeneity (ΔT<inf>max</inf>= 2.1 °C) compared to the case without door (ΔT<inf>max</inf>= 4.9 °C). The maximum air velocity in the air curtain of 0.6 m s−1 was observed at the discharge grille. The horizontal air velocity from the perforated plate was low (<0.2 m s−1) for all shelves. The loading percentage in the cabinet did not significantly affect the airflow rate through the perforated plate.
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A simplified heat transfer model of a closed refrigerated display cabinet
(2019-01-01)
Chaomuang, Nattawut
;
Laguerre, Onrawee
;
Flick, Denis
A simplified heat transfer model for a closed refrigerated display cabinet was developed based on a zonal approach. The developed model allows the prediction of time-averaged air and load temperatures at various positions in the display cabinet. These predicted values were compared with measured air and load temperatures. Good agreement was found between them with the maximum difference of 0.5°C for every studied position and the overall mean absolute error of 0.2°C. Air and load temperatures vary with positions. High temperature was observed at the front (highest value at the front top) and low at the back (lowest value at the back bottom). Based on the simulation, the cabinet thermal performance can be enhanced by minimizing the size of door gaps.

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