Title: Thermal Analysis of Historical Autoclave Data Using Science-Based Data Analytics Methods

Authors: Andrew Stewart, Janna Fabris, Clarence Terpstra, Mark Shead, Göran Fernlund and Anoush Poursartip

DOI: 10.33599/nasampe/s.20.0362

Abstract: In typical aerospace composites manufacturing practice, autoclave thermal data is used for verifying the compliance of parts to specifications while rarely being used to turn the raw data to actionable items to drive tooling, equipment and specification improvements that could result in increasing production efficiencies and reducing composites manufacturing risk. Currently, any historical data analysis that is performed on such data sets is often manual, inefficient and analyst dependent. Consequently, improvements to production, such as the optimization of existing autoclave loads, the optimal introduction of new parts and the systematic management of process upsets, are not routinely performed. Nine years of historic data from a production autoclave was investigated by composites manufacturing process simulation experts in order to extract actionable information. Thermal data from 4075 autoclave runs, totalling 75,130 individual parts with well over 200,000 thermocouples, was parsed into a NoSQL database and analyzed from a standard workstation PC. The local heat transfer coefficient for 24,373 parts were calculated from nearly 50,000 thermocouple traces using a lumped capacitance approach. The heat transfer coefficients showed a normally distributed response of 65.3±25.3 W/m^2 K. Almost all the heat transfer coefficient data fell between 0 and 200 W/m^2 K.

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Conference: SAMPE 2020 | Virtual Series

Publication Date: 2020/06/01

SKU: TP20-0000000362

Pages: 12

Price: FREE