Problemi projektovanja ventilacionih radijatora: Poređenja sa tradicionalnim dvopanelnim radijatorima
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Apstrakt
Na rad grejnih tela u prostoriji utiče njihova interakcija sa sistemom za ventilaciju. Radijator odaje više toplote kada je protok vazduha duž njegove površine za prenos toplote veći i kada je veća termička neravnoteža sa okolnim vazduhom. Proučavane su toplota koju odaje radijator i temperatura ugodnosti u jednoj maloj kancelariji u kojoj radi jedna osoba, i to tako što je menjano mesto otvora kroz koji ulazi ventilacioni vazduh. U dva od četiri ispitivana slučaja, ulaz za vazduh je bio postavljen između radijatorskih ploča, da bi se napravio sistem ventilacionih radijatora. Ispitivanja su vršena pomoću CFD simulacija i obuhvatala su vizuelizaciju uslova toplotne ugodnosti kao i poređenja toplote koju odaju radijatori. Model prostorije je odsisno ventiliran, sa brojem izmena vazduha koji je jednak broju koji se preporučuje za kancelarije u Švedskoj (7 l s–1 po osobi) i hladnim infiltracionim vazduhom (–5 ºC) uobičajenim za zimski dan u Stokholmu. Rezultati su pokazali da u ovakvim uslovima ventilacioni radijatori mogu da obezbede stabilnije toplotne klimatske uslove od onih koje obezbeđuje tradicionalni sistem sa radijatorima i ventilacijom. Pored toga, kada se primenjuju vetnilacioni radijatori, željene toplotne klimatske uslove moguće je postići temperaturom površine radijatora koja je za 7,8 ºC niža. Zaključeno je da u kancelarijama sa odsisnom ventilacijom, ventilacioni radijatori mogu da doprinesu uštedi energije i očuvanju životne sredine.
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Reference
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