Simulation Performance of a Ventilated Greenhouse Based on CFD Technology

doi:10.3969/j.issn.1000-6362.2015.02.005

Abstract

Abstract: Simulation model of the airflow and temperature in a naturally ventilated Chinese solar greenhouse was established by using a computational fluid dynamics （CFD） software. The model was tested by comparing observed data and simulated data. The distribution of temperature and airflow inside greenhouse was analyzed through the validated two-dimensional CFD model. The results showed that， when the top vent opened， the cold air outside went into the greenhouse from the lower of vent and went out from the upper of the vent. The airflow in greenhouse was relative low， as mainly affected by heat pressure. When the bottom vent opened， the cold air outside went into the greenhouse from the lower of vent and went out from the upper of the vent， and the airflow below the height of 0.5m in greenhouse was stronger. The distribution of temperature and airflow was similar. When both top and bottom vents opened， the cold air went into greenhouse from bottom vent and went out from top vent， and the airflow at vent was strongest. When only one vent （top or bottom） opened， the average temperature in the greenhouse was 300.0K， however the temperature inside was more even when the top vent opened. When both vents of top and bottom opened， the average temperature in the greenhouse was 299.0K， which was better for temperature decreasing than only one bent opening．

Key words: CFD model, Chinese solar greenhouse, Temperature field, Air flow field

FANG Hui， YANG Qichang， ZHANG Yi， LU Wei， ZHOU Bo， ZHOU Sheng. Simulation Performance of a Ventilated Greenhouse Based on CFD Technology[J]. Chinese Journal of Agrometeorology, 2015, 36(02): 155-160.

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