Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis (Jan 2016)
“Walczak’s Pipes” in the Greenhouse Heating System
Abstract
Diversified heating circuits inertia is particularly important by high variability of external conditions were the greenhouse is often overheated or large heat losses are noted. To meet these needs a new generation of heating pipes were used. They are hexagram-shaped pipes called “Walczak’s pipe”. Tubes of such shape have several times smaller volume in comparison with traditional heating pipes of the same outer diameter and higher stiffness. The preliminary assessment of the “Walczak’s pipe” installed in the greenhouse is highly positive. Compared with the traditional system it enables better heat management. In the first research stage, the thermal efficiency was defined in different ambient conditions at selected flow parameters and various water temperatures. With regard to the accepted flow values, it is notable that “Walczak’s pipe” has greater thermal efficiency per unit of power comparing with traditional tube. During the study, there was also a thermographic analysis of pipes’ surface performed and the heat flow distribution was determined. Analyzing the temperature distribution on the “Walczak’s pipe” remarkable are the areas with higher values comparing with standard tube. It can be concluded that in the heating system with “Walczak’s pipe” energy transferred by radiation increases. This is particularly advantageous solution to use in greenhouses. It allows to obtain a higher leafs temperature with respect to the ambient temperature (vegetation heating). This parameter has a beneficial effect on the vegetative growth of cultivated plants.
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