Application of POD algorithm for temperature prediction in aircraft RAT bay

Abstract

Ram air turbine（RAT）system is the emergency power generation system of the aircraft. It supplies power to the aircraft after the main AC power of the aircraft is cut off. RAT is stowed in the RAT bay in the non air tight area normally and deployed into the air flow under emergency conditions. The temperature of the RAT bay determines the deploy time of the RAT，thus affects the safety of the aircraft under emergency conditions. The temperature prediction of the RAT bay is of significance for the safety under emergency condition. The temperature，altitude，atmospheric static temperature，flight speed，and cabin temperatures around the RAT bay are analyzed as a whole through the proper orthogonal decomposition（POD），the POD algorithm is used to predict the temperature of the RAT bay. The results show that the energy distribution of the first order mode exceeds 99% of energy of all modals. After data normalization，the mean absolute error of the prediction results could reach 0.063 as the minimum，and the root square mean error could reach 0.07 as the minimum. The POD algorithm can effectively predict the temperature information of RAT bay through modal reconstruction based on the sample data.

Keywords

• proper orthogonal decomposition
• ram air turbine bay
• temperature prediction
• modal analysis