In-Flight Icing Simulation

In-flight icing is a safety-critical aspect of aircraft design, yet it is a highly complex physical phenomenon that is extremely difficult to replicate using expensive physical tests. Recent regulatory changes and industry focus on the particular hazards presented by high altitude ice crystals and supercooled large droplets (SLD) have further challenged the design process and the time to market for new aircraft and technology.

Commercial aircraft cruise at altitudes where adverse meteorological phenomena such as icing clouds are rare and can generally be avoided. But during take-off and landing, they may not be able to avoid crossing atmospheric layers where adverse flight conditions may be encountered at the worst possible time: at low speeds and high angles of attack, when even small amounts of ice build-up can radically degrade the carefully optimized aerodynamic performance of wings and control surfaces. Commercial aircraft are therefore fitted with ice protection systems and must be certified to fly safely in known icing conditions.

FENSAP-ICE provides leading three-dimensional, state-of-the-art, design and aid-to-certification simulation software to provide enhanced aerodynamic and in-flight icing protection solutions in a cost-effective manner by addressing all five major aspects of in-flight icing:

  1. Airflow
  2. Droplet and ice crystal impingement
  3. Ice accretion
  4. Aerodynamic degradation
  5. Anti- and de-icing heat loads

FENSAP-ICE is compatible with widely-used CAD-based mesh generators so it can often reuse the meshes already produced for aerodynamic studies. Having no significant geometric limitations, it is applicable to aircraft, rotorcraft, UAVs, jet engines, nacelles, probes, detectors and other installed systems. OptiGrid is an anisotropic mesh optimization tool that is included to easily obtain high quality mesh- and user-independent results.


  • Ice Accretion

    Calculate the shapes and roughness distributions of glaze, rime or mixed-type ice accretion on aircraft surfaces ranging from wings to air data probes.

  • Aerodynamic Performance Penalty Analysis

    Assess the adverse effects of ice accretion on aircraft surfaces, losses in lift-to-drag ratios, increased blockage of screens and engine passages, and more.

  • Ice Crystal and Supercooled Large Droplets

    FENSAP-ICE models supercooled large droplets and irregularly shaped ice crystals in compliance with the requirements of icing certification envelopes in Appendix O and Appendix D.

  • Turbomachinery Icing

    FENSAP-ICE predicts ice accretion due to droplets and ice crystal ingestion in the gas path of turbofan engine compressors.

  • Ice Protection System Analysis

    Assess the performance of bleed-air and electro-thermal IPS to ensure protection against adverse in-flight icing conditions.

  • Mesh Optimization with OptiGrid

    OptiGrid provides solution-based anisotropic mesh optimization for high-precision CFD simulations on unstructured hybrid grids at the lowest possible computational cost.