Authors: Silveston, P. L. And R. R. Hudgins
Download file:
Published in: CBE Journal » CBE Journal Volume 22 (1980)

Download RAW file:
Description: Part I of this paper (Silveston et al. 1980) concluded that heat savings up to 20% could be realized by eliminating condensation in a 400-m3 greenhouse covered with a double layer of plastic film. It was also demonstrated through cost calculations based on a quasi steady-state analysis of heat flow and humidity levels near sunset that the use of mechanical dehumidification was not attractive for this purpose even though condensation heat losses could be reduced by 75%. An alternative to mechanical de humidification is to increase the resistance to heat flow by forming a condensate layer on the innermost surface of the greenhouse skin. The concept is similar to that examined by Walker and Walton (1968) where the condensate reduces the thermal transmittance of polyethylene film, thereby lowering radiation heat losses. It is well-known that filmwise condensation provides greater heat transfer resistance than dropwise condensation. The dropwise mode is usually encountered in greenhouses. The object of this paper is to determine the energy savings expected by creating filmwise condensation. A comparison is then carried out to see whether the use of commercial or other wetting agents required to promote filmwise condensation can be economically justified.

Keywords: energy conservation through control of greenhouse humidity. ii. promotion of filmwise condensation
Citation: Silveston, P. L. and R. R. Hudgins 1980. ENERGY CONSERVATION THROUGH CONTROL OF GREENHOUSE HUMIDITY. II. PROMOTION OF FILMWISE CONDENSATION. Canadian Agricultural Engineering 22(2):133-136.
Volume: 22
Issue: 2
Pages 133 - 136
Date: 1980
Technical field:
Conference name:
Session name:

Other information:
Publication type: Journal
Coverage: Canada
Language 1:
Language 2:
Other files: