Calculation Features of the Combined Schemes of Cooling of Refrigeration UnitsCondensers / Particularitățile calculului circuitelor de răcire combinate pentru a condensatoarele mașinilor frigorifice / Особенности расчета комбинированных схем охлаждения конденсаторов холодильных машин

Modern requirements for energy saving and decrease in environmental pollution demandrevisingclassical technical and technology solutions of refrigeration unit production. Composite cooling application of refrigeration units allows condensers to reduce pollution of fresh waters, to reduce consumption of electric energy, to reduce condensation pressure, to use natural cold of the environment. In this work approach to thermal and mass balance determination of the refrigeration units with the combined cooling of condensers with intermediate discharge of liquid coolant between condensers of waterand air cooling is offered. Definition of an enthalpy before a throttling expansion (mix of the sated and overcooled liquid after condensation knot) taking into account dryness degree is specified. For influence assessment of this feature the numerical analysis on the example of the refrigeration units of the freon refrigeration units is carried out. Made change of refrigerating coefficient for the refrigerator with the combined cooling of rather classical scheme of condensation to 2.5%. Change of loadingson knot of condensation made 2.2%, on the evaporator of 2.5%. For calculation and the choice of the capital equipment of the refrigeration unit these changes will not exert decisive impact, and for regulation of refrigeration unit operating modes will have significant effect, especially at the large enterprises of oil processing branch and large transport objects. The received specification of refrigeration unit calculation is used in program modules of refrigeration unit calculation with the combined cooling of condensers and allowed to carry out the qualitative parametrical analysis of its work. Cerințele moderne pentru economisirea energiei și reducerea poluării mediului necesită revizuirea soluțiilor tehnice și tehnologice clasice în domeniul producției de mașini frigorifice. Mașinile de răcire cu condensatoare răcite cu apă sunt implicate în poluarea cu apă potabilă, iar la utilizarea condensatoarelor răcite cu aer, compresoarele consumă mai multă energie electrică. Aplicarea răcirii combinate a condensatoarelor mașinilor frigorifice permite reducerea poluării apei potabile, reducerea consumului de energie electrică, reducerea presiunii de condensare (regimul de funcționare cu eficiență ridicată a compresoarelor), utilizarea frigului natural al mediului. Cu toate acestea, nu a fost posibilă implementarea completă a acestei răciri, deoarece există incertitudini în