Development of a soil regenerator with a granular nozzle for greenhouses

• Main Authors: Irina Boshkova, Natalya Volgusheva, Antonina Solodka, Ihor Mukminov, Oksana Bondarenko
• Format: Article
• Language: English
• Published: PC Technology Center 2020-08-01
• Series: Eastern-European Journal of Enterprise Technologies
• Subjects: solar radiation; heat accumulation; heat calculation procedure; factor of intercomponent heat exchange
• Online Access: http://journals.uran.ua/eejet/article/view/210684

The results of the development of a regenerative-type heat exchange unit for greenhouses are presented. The creation of a soil regenerator is conditioned by energy and economic expediency. In spring in the daytime, the air in greenhouses is intensely heated by solar radiation, and at night it can be cooled below the allowable temperature. Heat accumulation during the day and using this heat at night will reduce the need for heaters even to their complete exclusion. The soil regenerator contains a dense layer of granular material that is blown through by the air from the inner space of a greenhouse. This solution makes it possible to intensify significantly the heat exchange. To determine the mean intercomponent heat exchange factor, the empirical dependence, taking into consideration the effect of duration of the heat exchange process, was obtained. We developed the procedure of thermal design calculation of a regenerator, using which the main geometric characteristics of the heat exchange area are determined. The results of the calculation of the soil regenerator for a greenhouse with the surface area of 18 m2 for the conditions of the warm continental climate were presented. The developed soil regenerator contains 5 channels that are 5.75 m long, filled with rubble. It was obtained that for the average solar radiation flow Qc=2,160 W and the duration of operation of the soil regenerator τΣ=6 hours, the accumulated heat at night can be consumed for 2.6 hours at the average ambient temperature t1=7 °C. As the ambient temperature rises, the time of regenerator operation will increase. The proposed soil regenerator is characterized by the design simplicity and its application will lead to an increase in energy costs to maintain the temperature mode in a greenhouse