In the context of the objective of the German government and the European Union's energy policy, it is crucial to increase the share of renewable energy. However, due to the fect that renewable engergy production due fluctuating wind and sun energy does not correlate with the customer demand, it is neccesary to compensate this energy generation gap with flexible power plants. Such plants need to be operated in a flexible load range. In this context, gas power plants play an important role because they allow rapid load changes and provide energy at high efficiencies.
Goal of the current project is the development of combustion technologies for climate-friendly energy conversion. The research that is to be done in subproject 1F serves to fulfill the subgoal "operational flexibility and fuel flexibility." The operational flexibility is critically dependent on the stability limits of the combustion, but their prediction is not adequately possible up-to-now. The fuel flexibility requires the safe design of burners that can be operated with both gaseous and liquid fuel.
One important way to foster climate-friendly power generation is the increase in the efficiency of gas turbines. Since the increase in the efficiency is related with the increase of the pressure and temperature levels of the process, the main objective is based on the optimization of the cooling of the highly stressed parts. Such an optimization can not be done without the knowledge of the temperature distribution in the combustion chamber and the combustion chamber outlet, which is also a primary goal of the project. The calculation of the temperature distribution or the distribution of heat release depends on the following sub-processes:
Detection of the droplet dispersion, which is dominated by the turbulent fluctuation movements
Calculation of evaporation, which depends on the evaporation characteristics and the turbulent heat transfer from the gaseous to the liquid phase
Analysis of the interaction between the turbulence and heat release
The true representation of the realistic subprocesses represent the scientific part of the project goals 1F
Calculated (LES) average temperature in the vicinity of an airblast nozzle using hexadecane as fuel (left: with - right without water addition).