20.500.12556/DKUM-94210 Energetska učinkovitost variabilne hladilne naprave Energy efficiency of variable cooling device Pojavlja se je vprašanje, kateri parametri vplivajo na učinkovitost delovanja hladilnika. V delu je najprej opisan princip delovanja hladilnika. V nadaljevanju je izveden analitični izračun hladilnega cikla. Z variiranjem je opazovan vpliv posameznih parametrov na eksergetsko razmerje in hladilno število. Rezultati so pokazali, da nižanje temperature hladilnika do temperature -15°C, kjer doseže vrednost 0,31, povečuje eksergijsko razmerje, nato to začne padati, pri 0°C ima vrednost 0,26. Višanje željenje temperature od -15°C navzgor, nima pozitivnega učinka na eksergijsko razmerje. Hkrati se čas delovanja podaljša, ob nižanju temperature v hladilnik, če želimo dosegati temperaturo -15°C namesto 0°C se čas hlajenja na dan skoraj podvoji Nižja temperaturna razlika med hladilnikom in temperaturo uparjanja privede do višje učinkovitosti, pri temperaturni razliki 4°C je vrednost hladilnega števila 5,75, med tem ko je pri temperaturni razliki 14°C vrednost 4,1. The question arose as to which parameters affect the efficiency of the refrigerator. The work first describes the principle of operation of the refrigerator. Subsequently, a theoretical calculation of the refrigeration cycle is performed. By varying it, the influence of individual parameters on the exergy efficiency and the cooling number is observed. The results showed that lowering the refrigerator temperature to a temperature of -15°C, where it reaches a value of 0,31, increases the exergy ratio, then it starts to fall, at 0°C it has a value of 0,26. Increasing the desired temperature from -15°C upwards has no positive effect on the exergy ratio. At the same time, the operating time is extended, when lowering the temperature in the refrigerator, if we want to reach a temperature of -15°C instead of 0°C, the cooling time per day almost doubles. A lower temperature difference between the refrigerator and the evaporation temperature leads to higher efficiency, at a temperature difference of 4°C the value of the cooling factor is 5,75, while at a temperature difference of 14°C the value is 4,1. hladilna naprava hladilno število eksergijski izkoristek izobutan R600a analitični izračun cooling device cooling number exergy efficiency Isobutane R600a theoretical calculation true true false [A. Poberžnik] Slovenski jezik Angleški jezik Diplomsko delo/naloga 2025-08-08 14:39:33 2025-09-25 15:05:05 2025-10-09 08:59:41 0000-00-00 00:00:00 2025 0 Maribor 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.56(043.2) 21843 UN_Poberznik_Aljaz_2025.pdf UN_Poberznik_Aljaz_2025.pdf 1 2E41D409FA5EE66BF49E6D392AF53B18 81cd9612d09266d34919c73171537afe944e49e1a584d5970040d53f6524686f 39bb9b69-75cf-11f0-a01d-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=195000 Fakulteta za strojništvo 0 0 0