Study On The Temperature And Humidity Control System Of Seedling Greenhouse In The Condition Of Heating Water

In order to improve the ability for the technology of float seedling system in winter, by using of circular heating nutrition to ensure the seedling needed for best growth temperature. This measure causes to high humidity and unstable temperature in the greenhouse.Aimed to this problem, the paper analyzed the water evaporation under the floating condition of heating water in floating seedling greenhouse and the related humidity model has been established. The greenhouse adopts the method of air-air heat exchange for insulation and dehumidification. This paper analyzed the influence of ventilation, temperature and humidity difference between inside and outside of greenhouse on the heat exchange efficiency through experiments.According to the temperature and humidity control of single floating seedling greenhouse. An insulation dehumidification heat exchange ventilator and a ventilator control system based on STM32 microcontroller were developed. The ventilator control system includes temperature and humidity sensor, single chip microcomputer, fan, valve control device and Human-computer interaction module. And the environmental parameters inside the greenhouse and ventilator working condition can be displayed on the system. According to the given environmental parameters, the temperature and humidity inside the greenhouse can be controlled automatically by the combination of motion control of fan and water valves.The remote monitoring system based on GPRS has been developed. This system could communicate with the heat exchange ventilator control system remotely and realize remote monitoring for greenhouse environment.The developed temperature and humidity control system has been applied in greenhouse nursery productive practice, the experiment data indicated that, the control system has good dehumidification effects, the average humidity of experimental greenhouse was 6.7% lower than the control greenhouse, the average energy recovery efficiency was 59.35%, the greenhouse seedling stem height increased 0.04cm, stem diameter increased 0.06cm.