The research describes the development of an evaporative cooling system in a non-refrigerated truck for the short-term storage of vegetables during transportation. The system comprises an evaporative cooler, storage unit, power supply, control panel, and real-time data monitoring for temperature  and relative humidity. Computational fluid dynamic (CFD) simulation was conducted to investigate the temperature and airflow distributions in the evaporative-cooled storage unit for five different configurations of air inlet and outlet. The configuration of one air inlet (front — lower left) and two air outlets (top — front and back centre) of the storage unit was shown to provide  optimum temperature and airflow distributions and hence, was applied in the system modification. The functionality and performance of the modified system were then evaluated in terms of the cooling profile of the storage units and leafy vegetable quality for the fresh market. Three storage treatments for the selected vegetable were investigated, i.e., evaporative-cooled truck (T1), canvas truck (T2), and cold truck (T3) during a five-hour journey from Cameron Highlands to Serdang. The average temperature inside the storage units was T3 < T1 < T2. Evaporative-cooled truck exhibited an average temperature reduction (DT) of 10°C from the ambient condition. It also demonstrated a relative humidity of >90%, which was in agreement with the recommended relative humidity for leafy vegetable storage. Post-five-hour storage treatments, vegetable stored under T1 exhibited the least weight loss as compared to T2 and T3. The results indicated that the evaporative cooling system manages to preserve vegetable quality soon after harvesting, hence the potential to reduce postharvest loss during transportation.

Computational fluid dynamics (CFD) have been playing an increasingly important role in designing the agriculture control environment structure in the past few years. Plant factory is a fully enclose control environment agriculture structure developed to create optimum growing conditions for the crops. Previous studies have proven that the CFD technique was able to analyse and predict the internal climate of the plant factory in the designing stage before the actual plant was built. This study was conducted to analyse the changes in airflow characteristics and temperature distribution in a shipping container size plant factory with different inlet and outlet locations. Uniformity of airflow and temperature distribution was important in plant factories as it is responsible to create optimum and uniform growing conditions for crops. The CFD model was validated by comparing simulation and experimental data of existing plant factory inlet and outlet location. The validation result shows an acceptable percentage error between simulated and measured data. Two alternative design of the inlet and outlet location was simulated to improve the uniformity of airflow and temperature distribution. The validated CFD model was then used to simulate the alternative design. Finally, the location of the inlet and the outlet that produce the most uniform airflow and temperature distribution inside the plant factory was identified.

Airflow is important in plant factories as it is responsible for the air exchange inside the structure to create desired growing conditions for plants. A uniform airflow distribution enhances photosynthesis and the transpiration process of the plants. In this study, computational fluid dynamics (CFD) analysis was used to analyse the airflow distribution inside a commercial scale plant factory developed by MARDI. CFD plays an important role in designing and optimisation of control environment structure in the agriculture industry. Many studies have proved that the CFD technique is able to predict the internal climate of the plant factory in the designing stage before the actual plant was built. This study was conducted to analyse the airflow characteristics in a plant factory with different inlet and outlet locations. The study also analyses the effect of different inlet location to the overall temperature distribution inside the plant factory. Validation of the developed CFD model was carried out by comparing simulation results with experimental data. The validation result showed an acceptable percentage error between simulated and actual data. The validated CFD model was then used to analyse different inlet locations that can produce more uniform airflow and temperature distribution inside the plant factory. From the simulation results, it shows that the new inlet location was able to produce more uniform airflow and temperature distribution as compared to existing inlet location.

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Cube-Grow was developed by MARDI to promote urban agriculture to the urban population. The product enables urban people to grow their vegetables with limited space. The initial test run of the system shows that the plant growth inside the structure was below expectation. The problem arises due to a lack of airflow or improper ventilation inside the structure. Optimum ventilation or airflow is crucial for plant growth as it enhances evapotranspiration at the leaf area to promote optimum plant growth. Therefore, this study aims to increase the airflow inside the Cube-Grow and find the best location for the air hole. Computational fluid dynamics (CFD) simulation was used in this study the analyse the effect of adding an air hole to the airflow characteristic inside the Cube-Grow. CFD also was used to select the best location to place the air hole. 3 option of air hole location was analysed and the results were compared with the existing design. The initial CFD simulation results were compared with the actual measurement data before it was used for further analysis. The result shows that adding an air hole increases overall airflow inside the Cube-Grow. Option 3 was chosen as the best location for the air hole as it produces a uniform and higher airflow inside the Cube-Grow. The study proved that CFD was able to be used to optimize the design of Cube-Grow before the actual prototype was built.