This topic under the European Defence Fund (EDF) 2026 Research Action call focuses on improving the design and operation of underwater platforms by advancing the ability to model and predict flow-related underwater noise. Flow-related noise generated by manned and uncrewed underwater platforms (including uncrewed underwater systems, manned underwater vehicles, and other underwater/surface platforms) can reduce the performance of onboard sonars and underwater communications and contributes to the overall radiated noise signature of the platform. The call therefore seeks accurate, validated modelling approaches that can be used during platform design, sonar placement and integration, and radiated-noise simulation.

The general objective is to enable optimal design and effective sonar integration by improving predictive capability for flow-related underwater noise. The specific objective is to develop and validate advanced models for predicting flow-related underwater noise and to generate high-quality verification data. The modelling work is expected to combine advanced numerical methods, including computational fluid dynamics (CFD) and acoustic simulations, and to push state-of-the-art approaches into parameter ranges relevant for silent underwater platforms.

A central element of the scope is the generation of controlled experimental data, notably through a buoyant body experiment that allows fundamental physical processes to be isolated. The study must cover self-noise in both flush-mounted and integrated hydrophones, as well as sonars measuring the radiated sound. In addition to the buoyant body experiment, the project should generate high-quality experimental reference datasets from various underwater platforms and sonar systems to validate numerical predictions. The proposal must also integrate experimental data and numerical modelling to validate and iteratively improve prediction accuracy.

The call defines eligible and mandatory activity types under the EDF Regulation: generating knowledge, integrating knowledge, and studies are mandatory; design activities are optional; prototyping, testing, qualification, certification, and other listed activities are ineligible. Mandatory tasks therefore include: generating experimental data from buoyant body experiments for self-noise and radiated noise; producing reference datasets for prediction of flow-related radiated noise; and delivering new insights into the governing physical processes. On the modelling side, the proposal must develop advanced numerical models incorporating existing CFD and acoustic knowledge, and systematically integrate experiments and simulations for validation. Study activities include planning and conducting the experiments, benchmarking existing modelling tools against measured data, and developing new or improved modelling tools and methods where needed.

Functionally, the resulting models and tools should be able to simulate multiple platform types (including UUS, manned underwater vehicles, underwater surface ships/systems and surface ships), account for environmental conditions such as water depth, temperature and salinity, and predict sonar performance in the presence of flow-related noise (including impacts on detection and classification). They should also support investigation of design and operational drivers such as hull shape, propulsion and manoeuvring, and deliver user-friendly software tools for predicting flow-related underwater noise and simulating sonar performance.

The expected impacts include strengthening the European Defence Technological and Industrial Base (EDTIB) and reducing dependencies on non-European suppliers, supporting strategic autonomy in underwater technologies, and improving interoperability among EU Member States’ and associated countries’ naval forces. Additional impacts include improved protocols and standardisation, enhanced command-and-control systems, improved safety and security of underwater technologies, and better support to underwater platform design and sonar placement and design.

Opening: 22.01.2026
Deadline(s): 29.09.2026