Skip to main content
European Commission logo
English English
CORDIS - EU research results

3D MUltidisciplinary tools for the Simulation of In-flight iCing due to High Altitude Ice Crystals

Periodic Reporting for period 3 - MUSIC-haic (3D MUltidisciplinary tools for the Simulation of In-flight iCing due to High Altitude Ice Crystals)

Reporting period: 2021-09-01 to 2023-02-28

Icing is a major hazard for aviation safety. Over the last decades an additional risk has been identified when flying in clouds with high concentrations of ice-crystals. In such conditions, it has been observed that ice accretion may occur on warm parts of the engine core, resulting in engine incidents such as loss of engine thrust, strong vibrations, blade damage, or even the inability to restart engines. Performing physical engine tests in icing wind tunnels being extremely challenging and expensive, the need for numerical simulation tools able to accurately predict ICI (Ice Crystal Icing) is urgent and paramount for the aeronautics industry, especially regarding the development of new generation engines (UHBR = Ultra High Bypass Ratio, CROR = Counter rotating Open Rotor, ATP = Advanced Turboprop) for which analysis methods largely based on previous engines experience may be less and less applicable.

The European research project MUSIC-haic has been conceived to fill this gap and has started in September 2018. MUSIC-haic brings together the main European research institutions working on icing modelling as well as engine manufacturers and aircraft manufacturers. The objectives of the project are to develop advanced ice crystal icing models, implement them in existing industrial 3D multi-disciplinary tools, and finally perform extensive validation of the new ICI numerical capability through comparison of numerical results with both academic and industrial experimental data.
The project is divided into 6 WPs, 4 technical ones (WP1 to WP4) and 2 dedicated to management and dissemination. WP1 aims to provide missing experimental data for model development & validation. WP2 aims to complete the development of a comprehensive set of models for ICI, building on previous projects outcomes and using WP1 experimental data. The aim of WP3 is to implement the new ICI into the partners’ existing 3D multidisciplinary tools and to provide ready-to-run tools for WP4 final validation tests (not started yet).

During the first 3 years of the project, numerous laboratory-scale experiments have been designed and performed to measure some rheological properties of an ice layer (apparent yield stress, characteristic time scale of water imbibition ...) to study the impact phenomena of ice crystals (in particular to characterize the size and velocity distributions of the fragments), as well as to study the accretion of the ice crystals and its coupling with the thermal conduction inside the wall. A new large experimental database has been created and made available to the modellers involved in WP2. In addition, a first set of experiments has been performed to study and better understand the ice shedding cycles. All corresponding test setups and results are described in deliverables D1.2 and D1.3 which will be publically released by the end of 2022.

In WP2, new models have been developed for ice layer rheological properties, ice crystal impact onto a rigid wall, erosion rate of an ice layer due ice particle impacts, ice accretion phenomena and their coupling with heat conduction in the substrate. These models have been
implemented in the existing 2D numerical tools and numerical tests performed to assess the ability of the models to reproduce WP1 experimental results. The optimal calibration & validation of models is still in progress. These models are described in deliverable D2.2&D2.3 to be publicly released end of 2022.

In WP3, tool requirements have been specified and synthesized in a common report (D3.1) released to all the partners and to the advisory board members. The WP3 partners also worked on the preparation of their 3D multidisciplinary computational tools for the implementation of the new ICI models. All 3D tools have been updated with the existing ICI models from the HAIC project. In addition, improvements and missing couplings were introduced in some of the tools to prepare for the integration of the new models and to enable the simulation of ice crystal accretion involving conjugate heat transfer phenomena. Conclusive numerical tests have also been carried out to verify that these developments have been properly completed and that the results obtained are in line with expectations. For most of the partners, the implementation of the new models (from WP2) in their 3D tools has not yet started. But their tools being now ready, the work will start soon and should be finished in time for the final validation phase (WP4).
To develop the new 3D ICI numerical capability, MUSIC-haic benefits from many important existing building blocks:
o Physical models: HAIC sub-project 6, which was devoted to models and tools development, made significant progress in the understanding of physical phenomena controlling ice crystal icing and led to the creation of a first generation of ICI models. All these models were implemented in 2D numerical research tools for the purpose of empirical constant calibration and first level validation.
o ICI physics experimental database: To support the development of ICI models, extensive experimental activities were performed within the HAIC project and in parallel, in the scope of North American projects, by the CNRC and NASA. These complementary experimental investigations allowed a large database to be created.
o ICI industrial database: HAIC-HIWC flight tests permitted the characterization of high altitude ice crystals properties and the collection of data for quantifying probe installation effects. Within the HAIC project, ICI tests with a Pitot probe were performed as well in the French DGA icing wind tunnel. In parallel, full engine tests (with a Honeywell ALF 502 turbofan engine) were performed in NASA’s large IWT (Propulsion Systems Laboratory - PSL).

Since the beginning of the project, significant progress beyond the state of the art has been made. First of all, the new experimental databases concerning the accretion and impact phenomena constitute major advances compared to the state of the art. Moreover, the experiments concerning the initiation of the accretion phenomenon and the coupling between ice accretion and thermal conduction in the wall in the presence of a heat source have allowed important progress in the understanding of these phenomena. Concerning the development of new models, the most important achievements are the development of new fragmentation and erosion models with a less empirical basis than the HAIC models, as well as the development of an extension of the classical Messinger model that takes into account both unsteady effects and the coupling with heat conduction in the wall and inside the ice layer. Last but not least, all partners have performed in parallel the necessary developments in their internal 3D multidisciplinary numerical tools, in order to prepare the implementation of the new ICI models.

In terms of potential impact of the project, the new ICI numerical capability will provide the European aeronautical industry with a tool to de-risk and optimize the design of new engines with breakthrough architecture, the efficiency of probes and their location on the nose and fuselage of aircraft, and to reduce the cost and duration of certification.
Experimental investigation of impact of ice crystal onto a solid surface by Airbus CRT Munich
Experimental investigation of impact of ice crystal onto a solid surface by Airbus CRT Munich
TUBS heated flat plate experiment - Wall temperature evolution after the onset of the icing cloud
Examples of the ice shapes on the TsAGI airfoil model, unheated mode
Numerical simulations of TUBS heated flat plate experiment for two different flow velocities