SENSITIVITY ANALYSIS AND UNCERTAINTY QUANTIFICATION FOR RIM SEAL INGESTION WITH 1-D NETWORK MODELS

摘要

Accurate prediction of turbine rim seal ingestion remains a challenge, even sophisticated unsteady computational models have had limited success due to the complexity and uncertainties present in this type of problems. For this reason, it is of interest to perform stochastic analysis taking into account the variability in the input parameters as well as uncertainties and assumptions associated with a given model of choice. This study focuses on a Secondary Air System (SAS) of a gas turbine, considering a generic cavity in a high pressure turbine (HPT) in which hot gas ingestion occurs and uncertainty in geometrical, operational and modelling parameters is present. Several statistical methods are applied to a 1D gas network model in order to evaluate the impact of the tolerances of the main geometrical parameters in the output, followed by a broader analysis including other operational and modelling variables. Results indicate that most influential parameters are the sealant mass flow rate, a modelling constant and the minimum gap of the wheelspace cavity.