THE APPLICATION OF RANKINE CYCLE FOR THE WASTE HEAT RECOVERY FROM DIESEL ENGINES

U radu se razmatra primjena Rankineovog procesa za iskorištenje otpadne topline iz diesel motora. Opisan je rad Rankineovog procesa te njegove osnovne komponente. Dana je usporedba klasičnog Rankineovog procesa s vodom kao radnom tvari te organskog Rankineovog procesa koji koristi etanol kao radnu tvar. U radu se analizira efikasnost Rankineovog procesa za korištenje otpadne topline ispušnih plinova iz diesel motora. Kao parametri efikasnosti uzeti su termički stupanj djelovanja procesa i dobiveni neto rad procesa. Napisan je matematički model i programski kod u software-skom paketu EES(Engineering equation solver). Kao rješenje problema priloženi su odgovarajući grafovi i tablice s podatcima. Izvršena je optimizacija procesa za vodu i etanol u rasponu temperatura radne tvari od 250 do 450 ºC te u rasponu tlakova od 5 do 30 bara. Nakon optimizacije utvrđeno je da je proces s vodom kao radnom tvari pogodniji za iskorištavanje otpadne topline.The application of Rankine cycle for waste heat recovery from a diesel engine is presented in this thesis. The operation of Rankine cycle and its basic components are described. The Rankine cycle with water as a working substance and the organic Rankine cycle utilizing ethanol are compared. The efficiency of Rankine cycle for waste heat recovery from exhaust gases of diesel engine is analyzed in this thesis. The thermal efficiency and net work output are taken as parameters for evaluation of the cycle. The mathematical model is created and program code in the software named engineering equation solver (EES) is written. The appropriate graphs and data tables are enclosed as a solution of the problem. Process optimization with water and ethanol in the temperature range from 250 to 450 ºC and in the pressure range from 5 to 30 bar is performed. After optimization it was concluded that the process with water is more suitable for waste heat recovery