Operation analysis of the air-source heat pump using TRNSYS simulation tool
Abstract
In order to achieve ambitious goals for energy efficiency and requirements for near zero energy buildings, various technological solutions enabling the use of renewable energy are proposed and applied. One such rapidly spreading technology is heat pumps. However, the use of air-to-water heat pumps in countries where the cold season is cold and humid has unfavourable conditions for the operation of this equipment during the heating season. As a result, the performance efficiency of the equipment decreases. This article presents the simulation results of an air-to-water heat pump operation in Lithuania using the TRNSYS modelling tool; its nominal heating capacity is 6.55 kW. The model was calibrated using real data obtained at Vilnius Gediminas Technical University when measurements were performed under heat pump freezing conditions. The seasonal performance factor of the heat pump heating mode was determined during the calculation. Parametric analysis of the model was also performed, when sensitivity of the model to the initial climatic data was observed. Comparable results are obtained for Vilnius, Prague and London.
Article in Lithuanian.
Šilumos siurblio oras–vanduo veikimo tyrimas taikant TRNSYS modeliavimo priemonę
Santrauka
Siekiant ambicingų energijos efektyvumo ir beveik energijos nevartojantiems pastatams keliamų reikalavimų ir tikslų, įvairūs technologiniai sprendimai, įgalinantys atsinaujinančiosios energijos vartojimą, siūlomi bei taikomi. Viena tokių sparčiai plintančių technologijų – šilumos siurbliai. Tačiau taikant šilumos siurblius oras–vanduo šalyse, kur šaltasis sezonas šaltas ir drėgnas, susiduriama su nepalankiomis sąlygomis šiai įrangai veikti šildymo sezono metu. Dėl šios priežasties įrangos veikimo efektyvumas mažėja. Šiame straipsnyje pristatomi šilumos siurblio oras–vanduo, kurio nominalioji šildymo galia 6,55 kW, veikimo analizės rezultatai Lietuvos klimato sąlygomis taikant TRNSYS modeliavimo priemonę. Darbui taikytas skaitinis modelis buvo kalibruotas naudojant realius duomenis, gautus Vilniaus Gedimino technikos universitete, kai eksperimentiniai matavimai atlikti esant šilumos siurblio užšalimo sąlygoms. Skaičiavimų metu nustatomas šilumos siurblio šildymo režimo efektyvumas. Modeliuojant taip pat atlikta modelio parametrinė analizė, kai stebima, kiek pradiniai klimato duomenys turi įtakos modelio rezultatams. Lyginami Vilniaus, Prahos ir Londono miestų klimato sąlygas atitinkantys modeliavimo rezultatai.
Reikšminiai žodžiai: eksperimentas, modeliavimas, šilumos siurblys oras–vanduo, sezoninis veiksmingumo koeficientas (SPF), šildymo sezonas, šilumos siurblio efektyvumas (COP), TRNSYS.
Keyword : experiment, simulation, air-source heat pump, seasonal performance factor (SPF), heating season, coefficient of performance (COP), TRNSYS
This work is licensed under a Creative Commons Attribution 4.0 International License.
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