Analiza termodinamičkog procesa s realnim radnim tvarima

undergraduate thesis

• Title (english): Analysis of a thermodynamic process with real working media
• Author: Robert Bedoić
• Mentor: Veljko Filipan (mentor)
• Committee member: Veljko Filipan (predsjednik povjerenstva)
• Committee member: Igor Sutlović (član povjerenstva)
• Committee member: Emi Govorčin Bajsić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2016-09-01, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Basic Technical Sciences; Thermodynamics

Abstract

U radu se ispituje utjecaj vrste radnih tvari i promjene režima rada na karakteristične veličine procesa u dizalici topline u režimu grijanja. Koristeći eksperimentalne podatke s geotermalne dizalice topline provjerava se točnost i primjenjivost tabličnog modela proračuna uz korištenje REFPROP baze termodinamičkih parametara za realne fluide. Nadalje, iz eksperimentalnih podataka analizira se prijelaz topline s tla na sekundarni fluid u bušotinskom izmjenjivaču topline, te procesi u ostalim izmjenjivačima topline, isparivaču i kondenzatoru. Termodinamički proces prikazuje se u odgovarajućim usporedbenim termodinamičkim dijagramima kako bi se zorno vidjela razlika svojstava radnih tvari i njihov utjecaj na energijske značajke dizalice topline. Ispituje se utjecaj izabrane radne tvari na karakteristične veličine u procesu pri čemu su obuhvaćene sljedeće radne tvari: propan, izobutan, nedopušteni R-12 i njegova ekološki prihvatljiva te široko prihvaćena zamjena R-134a, i za usporedbu amonijak kao najčešće korištena rashladna tvar. U režimu grijanja promatra se utjecaj promjene temperature isparavanja radne tvari na jedinični utrošeni rad, rashladni učin, toplinu kondenzacije, temperaturu nakon kompresije i faktor grijanja dizalice topline, uz konstantnu temperaturu (tlak) kondenzacije. Ispituje se također utjecaj promjene temperaturnog režima rada u dizalici topline na karakteristične veličine u procesu.

Abstract (english)

The aim of the work is to examine the influence of different refrigerants and different working conditions on specific energetic values in the heating mode of a heat pump. The possibility of applying spreadsheet calculator to a real thermodynamic process using the REFPROP base of thermodynamic parameters for real fluids is examined. Using experimental data taken from a geothermal heat pump there is also included the heat transfer from the ground to the secondary fluid in the borehole heat exchanger, and the processes in other heat exchangers, such as evaporator and condenser. Thermodynamic process is shown in the respective comparative thermodynamic diagrams in order to clearly see the different properties of refrigerants and their impact on the energy characteristics of the heat pump. Also, the energy characteristics of different refrigerants are analysed for the same temperature conditions. The following refrigerants are included: propane, isobutane, rejected R-12 and its environmentally friendly and widely accepted replacement R-134a, and for comparison ammonia as the most commonly used refrigerant. In the heating mode there is analysed how the changes in evaporation temperature of refrigerant at constant condensation temperature (pressure) influence the unit workloads, cooling capacity, heat of condensation, temperature after compression, and the heating coefficient of a heat pump. Furthermore, the influence of different temperature regime on characteristic energetic values is examined.

• Keywords: dizalica topline; termodinamički proces; REFPROP; realne radne tvari; prijelaz topline; izmjenjivači topline; termodinamički dijagrami; energetske veličine
• Keywords (english): heat pumps; thermodynamic process; REFPROP; real refrigerants; heat transfer; heat exchangers; thermodynamic diagrams; energy characteristics
• Language: croatian
• URN:NBN: urn:nbn:hr:149:600902
• Study programme: Title: Chemical Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2018-01-30 08:49:25