טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentYulia Banzger
SubjectInvestigation of Combustion Processes in Gas Turbine and Jet
Engines with Vaporizers
DepartmentDepartment of Aerospace Engineering
Supervisor Professor Emeritus Levy Yeshayahou


Abstract

Simulation of fuel spray combustion has a great importance for improvement of the jet engine performance. The processes involved are extremely complicated. The gaseous phase includes air, fuel vapor and combustion products. The liquid (fuel) phase is represented by fuel droplets injected into the vaporizer.

Existing numerical simulations described in the literature deal with a very limited number of modeled processes. The modeling performed in the present work embraces computation of viscous, compressible, turbulent, two-phase reacting flow, liquid fuel atomization and vaporization, droplet-wall interaction, one-step fuel (n-Heptane) oxidation, mass transfer and conjugate convection-conduction heat transfer. At the moment, there is no analytical solution for the stated problem. Computational Fluid Dynamics (CFD) code is used as the main tool for the present investigation and makes it possible to incorporate the relevant models of the involved physical processes.

The obtained results for liquid fuel combustion were compared to experimental data and to the results of computations performed for gaseous fuel. Parametric checks for droplet diameter influence and for droplet injection method were performed.

Results indicated good agreement with experimental data. In addition, it was found that:

·         In the liquid fueled model, the outlet maximum combustion temperature is higher, probably due to more complete combustion of the fuel.

·         There is a clear change in the temperature distribution due to change of phase of the fuel and droplet diameter.

·         Metal wall temperature is cooled down due to impingement of the liquid droplets on its surface.