CFD simulation approach in determining air conditioners position in the mini plant factory for shallot seed production

The precision agricultural development paradigm leads to the effort of controlling environmental parameters based on the suitability of needs, responses, and shallot crop performance. The distribution of temperature and air flow pattern have been required for growing. Furthermore, the temperatures less than 20°C is suitable or comfort for flowering initiation of shallot. Therefore, CFD simulation has been applied to compute temperature distribution and pattern with two alternate positions of air conditioners. The simulated domain is a chamber from container 40 ft with dimension of 672 × 212 × 261 cm. The room is equipped with 6 planting media shelves in the form of a substrate with a drip irrigation system. Each layer of the plant shelf is equipped with 4 units LED @ 20 W. The cooling source in the cultivation room comes from 2 AC units with a capacity of 2 pk. The position of the AC is placed on the front and rear walls with two different combinations, namely the top-top and top-center. Numerical approach was carried out to verify the results of the calculation, which used the grid convergence index with the number of cells around 1.7 million and the result of simulated air velocity value reached 0.27-0.30 ms-1. The air inside the chamber was cooled until the air temperature reaches 16-18 ° C by using 2 standard AC units. The top-top AC position was the best position with an air temperature uniformity of more than 99.5% for the entire shelf layer.