Conditional Neural Field based Reduced Order Model for Dynamic Ditching Load Prediction

TL;DR

This paper presents a conditional neural field approach for predicting aircraft ditching loads, demonstrating flexibility across different spatial discretizations and comparable accuracy to traditional grid-based models.

Contribution

The study introduces a neural field-based surrogate model that effectively predicts dynamic ditching loads with less parameters and greater flexibility than existing grid-dependent models.

Findings

Achieves near grid-based model accuracy with fewer parameters.

Successfully reconstructs loads across heterogeneous discretizations.

Enables flexible use of datasets from different geometries.

Abstract

Grid-based neural networks such as convolutional autoencoders are widely used in dimension reduction-based surrogate models for computational fluid dynamics. In recent years, the use of coordinate-based approaches like conditional neural fields has emerged. Their independence of the spatial discretization is a beneficial feature for various applications in computational fluid dynamics. This paper discusses the spatio-temporal prediction of aircraft ditching loads using a conditional neural field approach. The model is evaluated using two datasets for the dynamic loads of the fuselage of a DLR-D150 aircraft, one of which relates to a single fixed spatial discretization and the other that includes data from different discretizations. When paired with a long short-term memory (LSTM) network in the latent space, the neural field-based model achieves a spatio-temporal prediction accuracy for the first data set that is close to that of grid-dependent convolutional autoencoder-based models, and with significantly less parameters. Results for the second data set demonstrate the ability of the neural field-based approach to reconstruct ditching loads accurately for heterogeneous spatial discretizations. This allows for flexible use of training datasets generated for different geometries and/or discretizations, as well as the use of the surrogate model to predict loads for different configurations.