Improvement of Microclimate Conditions in Cab of Agricultural Machines by Using Localized Air Distribution

Abstract

Self-propelled agricultural machinery is mainly utilized during the warm period of the year. Under such conditions, due to solar radiation and other heat sources, inside conditions of operator's cab could become detrimental. Therefore, generating and maintaining of comfortable microclimate is very important aspect of ergonomics in the machinery cab. Conventional approach for cab microclimate conditions analyze is based on the presumption that there is homogenous state. Standards for indoor microclimate conditions also recommend minimal non-homogeneity. In reality, the conditions are usually non-homogenous and transient, but human body occupies only minor part of total cab interior volume and there are no much possibility for change the postures. Beside of this, individual parts of the body have different thermal sensitivity and different influence on overall thermal sensation and thermal comfort. This fact was used in this paper as a basis for research in field of non-uniformity of microclimate parameters in tractor cab by localized distribution of conditioned air.

Samohodna poljoprivredna mehanizacija se na našim prostorima najvećim delom eksploatiše u tzv. toplom delu godine. U tim uslovima, zbog sunčevog zračenja i drugih izvora toplote, kabina rukovaoca mašinom može postati prostor koji je krajnje nepogodan za boravak i rad čoveka. Iz tog razloga, važan aspekt ergonomije rada u kabini mobilne poljoprivredne mehanizacije jeste stvaranje i održavanje pogodne mikroklime. Konvencionalni pristup analizi mikroklimatskih uslova u kabini zasniva se na posmatranju prostora kabine kao homogenog. Takođe i standardi i norme kojima se propisuju mikroklimatski uslovi u zatvorenom prostoru preporučuju što manju nehomogenost. U realnosti, uslovi su obično izrazito nehomogeni i promenljivi u vremenu, a čovekovo telo zauzima samo manji deo zapremine unutrašnjosti kabine i nema mnogo mogućnosti za promenu položaja. Pored toga, pojedini delovi čovekovog tela imaju različitu toplotnu osetljivost i različito utiču na ukupni topotni osećaj i toplotni komfor, što je u ovom radu iskorišćeno kao osnova za istraživanje u pravcu generisanja kontrolisane neuniformnosti mikroklimatskih parametara lokalizovanom distribucijom kondicioniranog vazduha u traktorskoj kabini.