Numerical analysis of combustion process and thermal load of gasoline direct injection (gdi) engine

Razvoj motorjev z notranjim zgorevanjem v glavni meri narekujejo ekonomski, ter strogi ekološki normativi, ki zahtevajo globalno znižanje emisij izpušnih plinov. Tako se v avtomobilski industriji pojavlja trend manjšanja pogonskih agregatov (»down-sizing«), s katerimi proizvajalci lažje izpolnjujejo zastavljene cilje. Glavna pomanjkljivost teh motorjev je odvajanje sproščene toplote, saj se na manjšem volumnu sprosti večja količina energije. Magistrska naloga predstavlja numerično analizo termične obremenitve bencinskega GDI motorja. Prvi del predstavlja numerično analizo celotnega cikla štiri taktnega motorja, drugi del pa predstavlja termično analizo vitalnih delov strukture in hladilnega medija. Vse simulacije so bile izvedene s programskim paketom AVL FIRE. Rezultati simulacij so bili primerjani z referenčnimi 1D rezultati in predhodno izvedenimi meritvami obstoječega motorja.Today, development of internal combustion engines (ICE) is mainly guided by economic and ecological measures, where the focus of the latter is mainly on reduction of exhaust gas emissions. To achieve these goals, concept of engine downsizing has proven to be the most effective method, therefore it is extensively used by manufacturers. However, the main downside of the concept is increased thermal load due to greater ratio between released heat and total engine volume. The thesis introduces numerical analysis of gasoline GDI engine, focusing on thermal load. It consists of two partsthe first part considers CFD analysis of the whole engine cycle, while the second part estimates the thermal load by considering all the important structural parts and the cooling system. The presented simulations were created with AVL FIRE software. Simulation results were then compared to reference data in terms of calibrated 1D simulation and engine test bed measurements