Thermal analysis of forced-air and thermosyphon cooling systems for the Inuvik airport expansion

Abstract

This paper presents a description of thermal analyses of forced-air ventilation and thermosyphon cooling systems, which were carried out in connection with the design of the concrete raft foundations that support hangars and other major structures to be constructed by the Department of National Defence adjacent to the existing airport near Inuvik, N.W.T. The cooling systems are required to prevent heat from the buildings from thawing the ice-rich permafrost present below the site. The analyses identified those parameters that have the most significant effect on the efficiency of each system. Based partially on the results of the analyses, it was decided to utilize air ventilation for cooling. The system is expected to perform satisfactorily under natural convection; however, the design includes a provision to install air blowers, if this should prove necessary in the future. A number of areas in which further,zesearch appears useful have been identified.Cet article prCsente une description des analyses thermiques des systkmes de ventilation d'air force et de thermosyphons qui ont CtC rCalisCes en relation avec la conception de fondations de radiers de bCton supportant des hangars et autres structures majeures qui doivent hre construites par le DCpartement de la DCfense Nationale, a cBtC de 17aCroport d71nuvik, T.N.-0. Les systkmes de refroidissernent sont nkcessaires pour empCcher la chaleur des bltiments de faire fondre le pergCliso1 riche en glace sous le site. Les analyses ont identifie ceux parmi les paramktres qui ont l'effet le plus significatif sur I'efficacitC de chaque systkme. En se basant partiellement sur les rCsultats des analyses, l'on a dCcidC d'utiliser la ventilation d'air pour le refroidissement. L'on s'attend a ce que la performance du systkme soit satisfaisante dans des conditions de convexion naturelle; cependant, la conception offre la possibilitC d'installer des ventilateurs s'ils devenaient nCcessaires dans le futur. Un certain nombre de domaines dans lesquels de la recherche semblerait utile ont Ct C identifies.

Permafrost and climate in Europe: Monitoring and modelling thermal, geomorphological and geotechnical responses

“…Even during pre-construction activities, thermal disturbances should be minimised through the use of insulation materials (Thalparpan 2000) and drilling using chilled air flushing rather than fluids (Arenson, 2002;. Passive cooling systems such as thermosyphons, thermoprobes, air-duct cooling systems and gravity-driven air convection offer another possibility (Smith et al, 1991;McKenna and Biggar, 1998;Goering et al, 2000;Goering, 1998;Cheng, 2005;Wen et al, 2005;Arenson et al, 2006;Ma et al, 2006), but their efficiency in alpine environments is still to be tested.…”

Permafrost changes and engineering stability in Qinghai-Xizang Plateau

“…Thermosiphon, a one-way heat conducting-device that can bring the heat amount out of the embankment by conducting a "cooling amount" of air in winter into the embankment, has a better effect on the cooling roadbed. It is widely used in permafrost regions in Canada and the US [78][79][80] as well as in QXH and QXR [81][82][83][84]. Ventiduct embankments can effectively decrease permafrost temperature beneath the embankment by enforcing convection [85,86], which shows an ability to adapt to climate change [87][88][89].…”

Thermal performance of a combined cooling method of thermosyphons and insulation boards for tower foundation soils along the Qinghai–Tibet Power Transmission Line

“…A thermosyphon works as an effective thermal semiconductor, which is achieved by evaporation of the working liquid in the evaporator section, condensing in the condenser section and returning of the condensate (Noie, 2005). Thermosyphons of various designs have been widely used for cooling of foundation soils of buildings, roads, railroads and pipelines in northern and permafrost regions (Esch, 1988;Hayley et al, 1983;Heuer, 1979;Leong and Hornby, 1996;Smith, et al, 1991;Terry, 1987). In recent years, thermosyphons were used as a mitigation method for roadway and railway embankments experiencing large settlement on the QTP (Ma et al, 2009;Song et al, 2013;Yu et al, 2014).…”