An Investigation Into the Uncertainty of Turbomachinery Disc Heat Transfer Calculations Using Monte Carlo Simulation Methods

Abstract

The uncertainty in heat transfer data derived from theoretical turbomachinery disc temperatures has been investigated using Monte Carlo simulation methods. Two specific test cases of relevance to turbine disc heat transfer have been considered, a free disc with laminar flow and a free disc with turbulent flow. This study explores and quantifies uncertainties for the test cases considered by looking at three factors: measurement noise, the order of magnitude of the polynomial fit used for interpolation through the data points and the number of data points utilised within the polynomial. The local heat flux uncertainty arising from using a 5th order polynomial for the laminar case varied between approximately ± 40 % and ± 600 % and for the turbulent case between approximately ± 4 % and ± 1000 %. This study provides guidelines for similar analyses and the resulting uncertainty and how test data can be presented.