Parametric Analysis of a Radiant Gas Heating System for Controlled-Environment Agriculture with Preheated Ventilation

Abstract

This article explores the fundamental principles of the software method for calculating the gas-fired heating system of a cultivation structure, where the main source of heat is provided by ceiling-mounted gas infrared radiators. To maintain the required thermal regime within the premises, a gas air heater is utilized, designed to preheat the outdoor air to the necessary temperature before supplying it to the heated space.The calculation method is based on solving a system of interconnected equations of thermal and material balances for the cultivation structure, its enclosure, and the soil surface. Possible utilization of thermal energy from high-potential combustion products of gaseous fuel is taken into account.Using the example of the “Farmer 7.5” industrial greenhouse (Russian Federation), designed for year-round cultivation of plants in closed soil (in this case, cucumbers were the subject of study until the fruitbearing stage in the winter-spring cycle), the impacts of various factors are investigated: outside air temperature, thermal resistance of the enclosing structure on the heating system’s thermal power (in combination with the gas air heater), and variable parameters of the microclimate. The latter includes the enclosure temperature of the industrial greenhouse and the intake air temperature for general exchange ventilation needs. Specific conclusions and prospects for further scientific research are drawn based on the obtained results.