Title: RAIN EROSION: FROM MULTI-PHYSICS MODELLING TO EFFICIENT & COST-EFFECTIVE CERTIFICATION
Authors: Collins S. Davis, Allen Kim, Mira Tipirneni, Scott A. Adams, Jim Grossnickel, Jill Seebergh, Kjersta Larson-Smith, Jon Gabrys, Richard Laverty, Kenneth Young, Junlan Wang, Antonino Ferrante, Marco Salviato
Abstract: Currently, there is no accurate method to model the erosion of exterior aircraft surfaces by rain during flight. For qualification, all exterior coatings are put through the rigorous whirling arm test which is expensive and time consuming. The primary objective of this research project is to develop novel experimental and simulation techniques to predict the rain erosion degradation of coatings used by the aerospace industry. With the use of Finite Element Modelling, physical testing can be limited; thereby lowering costs, reducing time to market, and streamlining the qualification process.
To accomplish such a goal, it is necessary to characterize various coating materials. The methodology for this begins with tension testing to find the tensile stress-strain behavior and nanoindentation testing from which the compressive behavior is derived. The materials’ properties are then used as input in a Finite Element Model (FEM). Next, the results from Computational Fluid Dynamics (CFD) simulations can be combined with material profiles in order to model rain erosion across aircraft exteriors.
Preliminary simulations include a full 3D, elasto-viscoplastic model showing promising results matching the expected material response.
References:  Gohardani, Omid. “Impact of erosion testing aspects on current and future flight conditions.” Progress in Aerospace Sciences 47 (2011): 280-303  “Aircraft Surface Coatings: Energy Efficient Transport Program.” Boeing Commercial Airplane Company, NASA Contract Report 165928, 1982.  Schmitt, George F. “Flight Test-Whirling Arm Correlation of Rain Erosion Resistance of Materials: Technical Report AFML-TR-67-420.” Air Force Materials Laboratory, Wright-Patterson Airforce Base, Ohio, 1968.  Verma, A. S., Castro, S., Jiang, Z., Teuwen, J. “Numerical investigation of rain droplet impact on offshore wind turbine blades under different rainfall conditions: A parametric study.” Composite Structures 241 (2020): 1-20.  ASTM Standard D1708-18, 2018, “Standard Test Method for Tensile Properties of Plastics by Use of Microtensile Specimens” ASTM International, West Conshohocken, PA, DOI: 10.1520/D1708-18, www.astm.org  “Discovery Hybrid Rheometer.” TA Instruments  GOM Correlate Pro. GOM Metrology, 2022.  Oliver, W. C. & Pharr, G. M. “Measurement of hardness and elastic modulus by instrumented indentation: Advances in understanding and refinements to methodology.” Journal of Materials Research 19, 3-20 (2004)  “LS-Dyna Keyword User’s Manual Volume II: Material Models.” Livermore, California: Livermore Software Technology, 2021.  A, Mo “Berkovich and Flat Punch indenter tips.” 9 Jan, 2015, Grab Cad. > https://grabcad.com/library/berkovich-and-flat-punch-indenter-tips-1<  “LS-Dyna Keyword User’s Manual Volume I” Livermore, California: Livermore Software Technology, 2021..  Meißner, P., Winter, Jens., Vietor, T. “Methodology for Neural Network-Based Material Card Calibration Using LS-Dyna MATL_187_SAMP-1 Considering Failure with GISSMO.” Materials 15(643) (2022). DOI: 10.3390/ma15020643  Hernandez, C., Maranon, A., Ashcroft, I. A., Casas-Rodriguez, J. P. “A computational determination of the Cowper-Symonds parameters from a single Taylor Test.” Applied Mathematical Modelling 37 (2013): 4698-4708.
Conference: SAMPE 2023
Publication Date: 2023/04/17
Price: $30.00Get This Paper