A CONTRIBUTION TO THE CALCULATION IN STEAM TURBINE COGENERATION SYSTEM WITH CHANGING OPERATION CONDITIONS

Sažetak:Doktorskom disertacijom izvršena su teoretska i eksperimentalna istraživanja rada kondenzacijske parne turbine s reguliranim oduzimanjem pare kodpromjenjivih opterećenja. Teoretska ispitivanja izvršena su na osnovu predstavljenog matematičkog modela. Matematičkim modelom parna turbina je podijeljena na visokotlačni dio i niskotlačni dio. Visokotlačni dio turbine podrazumijeva područje protoka pare kroz regulaciono kolo i drugi stupanj, tj. do reguliranog oduzimanja pare dok na niskotlačni dio otpada područje rada nakon reguliranog oduzimanja pa sve do ispuha pare u kondenzator. Na bazi dobivenih rezultata konstruiran je dijagram promjenjivih režima rada u ovisnosti o ulaznoj količini pare, reguliranog oduzimanja te ostvarenoj električnoj snazi.U eksperimentalnom dijelu rada obavljena su mjerenja u realnim pogonskim uvjetima pod raznim režimima opterećenja turbogeneratorskog postrojenja instaliranog u kogeneracijskoj energani Rafinerije nafte Rijeka lokacija Mlaka. Na osnovu raspoloživih podataka o potrošnji energije u procesnim postrojenjima definirana su četrdeset i dva režima rada. Dobiveni rezultati eksperimentalnim mjerenjima relevantni su pokazatelji rada ispitivanog postrojenja.Analizom dobivenih rezultata ustanovljena su odstupanja teoretskih od eksperimentalnih istraživanja. Na osnovu dobivenih odstupanja, matematički model je korigiran korekcijskim faktorima za specifičnu potrošnju pare i ostvarenu električnu snagu prema rezultatima dobivenim eksperimentalnim mjerenjima. Odstupanja postoje iz razloga što matematički model ne uzima u potpunosti u obzir specifičnosti pojedinih izvedbi parnih turbina koje utječu na gubitke protočnog dijela. Navedenim faktorima dat je prilog proračunu parne turbine u kogeneracijskom sustavu s promjenjivim uvjetima pogona.Summary:This doctoral dissertation has been performed theoretical and experimental research of condensing steam turbine with controlled extraction in different operation mode.Theoretical examinations have been made on the basis of the presented mathematical model. Mathematical model of a steam turbine is divided into high and low pressure part. High-pressure turbine part includes the area of flow of steam through regulating wheel and a second stage, that is up the regulated extraction, while the low pressure part implies the area after the regulated extraction to the exhaust steam into the condenser. Based on the results of research, there has been constructed the diagram of changing operation mode depending on the input quantity of steam, the regulated extraction and electrical power.In the experimental part of the doctoral dissertation there have been performed some measurements in objective operative conditions under various regimes of load turbogenerator plant which is installed in CHP power plant of Refinery Rijeka Mlaka. There have been defined forty-two operation modes based on available data on energy consumption in process plants. The obtained results of experimental measurements are relevant indicators of the tested plants. The analysis of the obtained results has been found certain theoretical deviations from the experimental studies. With regard to the obtained deviations the mathematical model has been corrected according to correction factors for the specific consumption of steam and produced electric power towards the results obtained by experimental measurements. These deviations exist because the mathematical model does not consider specificities of individual design steam turbine that affect the flow losses. These factors give the contribution to calculation in the steam turbine cogeneration system with varying operating conditions