Map Estimation for Impingement Cooling with a Fast Extremum Seeking Algorithm

In many actively controlled processes, such as active flow or combustion control, a set of actuation parameters has to be specified, ranging from actuation frequency to pulse width to geometrical parameters such as actuator spacing. As a specific example, impingement cooling is considered here. Finding the optimal parameters for impingement cooling with steady-state measurements is a time consuming process because of the necessary time to reach thermal equilibrium. This work presents an algorithm for fast extremum seeking to reduce the amount of time needed. It is inspired by an Extremum Seeking Controller, which is a simple but powerful feedback control technique. The first results using this concept are promising, as the magnitude of the optimal pulse frequency for the cooling efficiency of pulsed impingement jets could be found with sufficient precision in a short period of time. The main advantages of this concept are the simple execution on a test rig, its versatility, and the fact that almost no information about the investigated system is necessary.