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Application of energy and exergy analysis to investigate the operation of an air handling unit with heat pump

Abstract

With the growth of energy-efficient building sector, ventilation systems are becoming increasingly important not only of fresh air supply but also in terms of energy consumption. The aim of this paper is to describe and analyse the operation of an air handling unit (AHU) with a heat pump using energy and exergy analyses under the variable environmental temperature (from –30 °C to 10 °C). The application of selected methods is illustrated in a case study of an AHU using environmental temperatures of Vilnius city during heating season (from the beginning of October to the end of April). An analytical method for determining distribution of the environmental (outdoor air) temperature is used. Energy and exergy analyses showed periods when the highest amounts of energy and exergy were consumed and the greatest exergy losses occurred. This allowed to reveal the component of the system with the highest exergy losses – the heat pump evaporator. Therefore, further research is needed for its design and application. At the end of the article, the seasonal indicators of the AHU with heat pump operation were calculated: coefficient of performance and exergy efficiency. The presented research procedure could be applied to the analysis of other energy systems and processes in them.


Article in Lithuanian.


Energinės ir ekserginės analizės taikymas oro paruošimo įrenginio su šilumos siurbliu veikimui tirti


Santrauka


Augant energiškai efektyvių pastatų sektoriui, vėdinimo sistemos tampa vis svarbesnės ne tik tiekiant švarų orą, bet ir vartojant energiją. Šio straipsnio tikslas – aprašyti ir išnagrinėti oro paruošimo įrenginio (OPĮ) su šilumos siurbliu veikimą energinės ir ekserginės analizės metodais, kartu atsižvelgiant į kintamą aplinkos oro temperatūrą šaltuoju sezonu (nuo –30 °C iki 10 °C). Pasirinktų metodų pritaikymas iliustruojamas atskiru OPĮ atveju – naudojant Vilniaus miesto aplinkos oro temperatūras šildymo sezono metu (nuo spalio pradžios iki balandžio pabaigos). Skaičiuoti taikytas analitinis lauko oro temperatūros pasiskirstymo nustatymo metodas. Atlikta energinė ir ekserginė analizė leido nustatyti laikotarpius, kai suvartojami didžiausi energijos ir eksergijos kiekiai bei patiriama didžiausių eksergijos nuostolių. Tai suteikė galimybę atskleisti sistemos komponentą, kuriame patiriama didžiausių eksergijos nuostolių – tai šilumos siurblio garintuvas. Todėl jam projektuoti ir naudoti turi būti skirti papildomi tyrimai. Straipsnio pabaigoje apskaičiuoti OPĮ su šilumos siurbliu veikimo sezoniniai rodikliai: veiksmingumo koeficientas ir ekserginis naudingumas. Pateikta tyrimo eiga gali būti pritaikoma kitų energinių sistemų ir juose vykstančių procesų analizei.


Reikšminiai žodžiai: ekserginė analizė, energinė analizė, oro paruošimo įrenginys su šilumos siurbliu, sezoninis ekserginis naudingumas, sezoninis veiksmingumo koeficientas (SCOP), ŠVOK sistemos.

Keyword : exergy analysis, energy analysis, air handling unit with heat pump, seasonal exergy efficiency, seasonal coefficient of performance (SCOP), HVAC systems

How to Cite
Streckienė, G., & Kropas, T. (2020). Application of energy and exergy analysis to investigate the operation of an air handling unit with heat pump. Mokslas – Lietuvos Ateitis / Science – Future of Lithuania, 12. https://doi.org/10.3846/mla.2020.13064
Published in Issue
Sep 21, 2020
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