Periodic Reporting for period 5 - NO-ICE-ROTOR (Development and demonstration of materials and manufacturing process for ultra high reliability electric Anti-ice/De-ice thermal layers for high strain rotor blades and helicopter airframe sections)
Berichtszeitraum: 2022-07-01 bis 2023-01-31
Every icing incident of airplane components may have serious consequences for aircraft flying performance and can even lead to fatal accidents. The statistics on ice- related accidents, reporting of more than 10.000 accidents between 1982 and 2001, make it very clear that ice prevention measures are of great importance.
Ice shapes on aircraft components can have substantial effects on lift, drag, and pitching moment. Even very little surface roughness caused by a thin ice layer generates significant aerodynamic effects, such as a precipitous drop in lift caused by flow separation. Ice accretion can be especially dangerous and fatal on propellers and rotors, significantly reducing propeller or rotor performance.
For tilt rotor aircraft, in-flight icing is an even greater issue - as a balanced and even power output between the two rotors is essential in all phases of flight. Uneven ice accretion between the two rotors, which may be caused by uncontrolled, uneven ice shed, will result in different efficiency and performance output between the two rotors on either side of the centre of gravity, resulting in a severe unbalance of the aircraft.
Furthermore, ballistic shedding of larger ice pieces may cause severe damage on the aircraft fuselage.
Taking all these factors into account, ice protection systems for tilt-rotor aircraft must be designed in a smart way in order to ensure sufficient safety in all weather conditions. Despite a large number of conventional approaches, anti-icing and the removal of existing ice on tilt-rotors are still not completely and satisfactorily solved.
The expected outcome of project NO-ICE-ROTOR is the development, manufacture and environmental test validation of ultra high reliability heater layers for future platforms.
The overall objectives of the project are:
o Design and development of electrically operated heater layers, to be embedded in the rotor blade structure up to a certain TRL
o Definition of test criteria and test matrix
o Manufacturing of suitable test specimens for structural-, and environmental coupon testing and ice wind tunnel testing
o Environmental testing at coupon level
o Structural testing at coupon level
o Ice wind tunnel, in both static-, and rotating configuration at full-scale level with fully functional prop rotor blade section
o Synthesis of testing results
Ice shapes on aircraft components can have substantial effects on lift, drag, and pitching moment. Even very little surface roughness caused by a thin ice layer generates significant aerodynamic effects, such as a precipitous drop in lift caused by flow separation. Ice accretion can be especially dangerous and fatal on propellers and rotors, significantly reducing propeller or rotor performance.
For tilt rotor aircraft, in-flight icing is an even greater issue - as a balanced and even power output between the two rotors is essential in all phases of flight. Uneven ice accretion between the two rotors, which may be caused by uncontrolled, uneven ice shed, will result in different efficiency and performance output between the two rotors on either side of the centre of gravity, resulting in a severe unbalance of the aircraft.
Furthermore, ballistic shedding of larger ice pieces may cause severe damage on the aircraft fuselage.
Taking all these factors into account, ice protection systems for tilt-rotor aircraft must be designed in a smart way in order to ensure sufficient safety in all weather conditions. Despite a large number of conventional approaches, anti-icing and the removal of existing ice on tilt-rotors are still not completely and satisfactorily solved.
The expected outcome of project NO-ICE-ROTOR is the development, manufacture and environmental test validation of ultra high reliability heater layers for future platforms.
The overall objectives of the project are:
o Design and development of electrically operated heater layers, to be embedded in the rotor blade structure up to a certain TRL
o Definition of test criteria and test matrix
o Manufacturing of suitable test specimens for structural-, and environmental coupon testing and ice wind tunnel testing
o Environmental testing at coupon level
o Structural testing at coupon level
o Ice wind tunnel, in both static-, and rotating configuration at full-scale level with fully functional prop rotor blade section
o Synthesis of testing results
WP 1 is related to Management including risk management, coordination, and communication within the project team as well as with the TM, is done by Villinger. In order to ensure proper management and coordination of the project, weekly telecons are being held between the TM and the consortium.
With regards to disseminationa and exploitation, several actions were taken also after the project End. A workshop with several people from Propeller industrie has been held to show possibe rotorblade/propeller IPS applications. In addition, attendance during SAE conference in Vienna 2023 was used to dissiminate the project results.
WP2:
Under the framework of WP2, the design and development of the heater layer-based IPS to be incorporated into a prop rotor or panel composite structure will be delivered. CFD simulations were performed in order to determine the requirements for the heater layer in terms of location and arrangement of heating zones on the rotor blade and power density for anti- icing and de-icing strategies. A number of anti-icing and de-icing zones along the rotor blade have been defined to ensure proper ice protection properties.
WP3:
The general works performed in WP3 was the realization, verification and preliminary testing of the Villinger heater layers on coupon level.
Partner CEST has performed extensive material characterisation and qualification tests of coupons combined with the evaluation of materials safety and compatibility in accordance to the DO160 specification. For this testing campaign, rectangular-shaped flat coupons provided by the TM to Villinger and equipped with different heater layer configurations have been used.
The outcome of this test campaign was to show compliance against all required environmental hazards and to test surface quality and uniformity of the Villinger heater layer applied on GFRP coupons.
WP4:
In WP4, structural element test specimen, representative of the actual system design later applied to a blade specimen, were manufactured for structural testing at Aviatest's facility. 5 coupons, consisting only of the structural laminate base material, without electrical elements included, were tested to establish the laminate strength and failure modes.
Furthermore, differernt Coupon types with functioning electrical elements, including the heater layer, busbars and cables were produced in order to establish the material testing in WP6.
WP5:
In WP5, the static specimen heater mats were produced successfully implemented into the environmental demonstrators.
In addition, heater mat coupons for various tests were manufactured
WP6:
In WP6, structural testing of various test coupons is done. There were some failures in the bus bars as well as in the substrate materials, for this reason. the loads were revised and additional testing is performed. The endurance testing could be finished.
WP7:
The main works performed in WP7 was preliminary testing of the environmental prop rotor spin demonostrator as well as the static testing on two demonstrators (mid-wing and root specimen) in the RTA Icing Wind tunnel.
WP8 & WP9:
During WP8 and WP9 the results from both environmental and structural testing were analized.
With regards to disseminationa and exploitation, several actions were taken also after the project End. A workshop with several people from Propeller industrie has been held to show possibe rotorblade/propeller IPS applications. In addition, attendance during SAE conference in Vienna 2023 was used to dissiminate the project results.
WP2:
Under the framework of WP2, the design and development of the heater layer-based IPS to be incorporated into a prop rotor or panel composite structure will be delivered. CFD simulations were performed in order to determine the requirements for the heater layer in terms of location and arrangement of heating zones on the rotor blade and power density for anti- icing and de-icing strategies. A number of anti-icing and de-icing zones along the rotor blade have been defined to ensure proper ice protection properties.
WP3:
The general works performed in WP3 was the realization, verification and preliminary testing of the Villinger heater layers on coupon level.
Partner CEST has performed extensive material characterisation and qualification tests of coupons combined with the evaluation of materials safety and compatibility in accordance to the DO160 specification. For this testing campaign, rectangular-shaped flat coupons provided by the TM to Villinger and equipped with different heater layer configurations have been used.
The outcome of this test campaign was to show compliance against all required environmental hazards and to test surface quality and uniformity of the Villinger heater layer applied on GFRP coupons.
WP4:
In WP4, structural element test specimen, representative of the actual system design later applied to a blade specimen, were manufactured for structural testing at Aviatest's facility. 5 coupons, consisting only of the structural laminate base material, without electrical elements included, were tested to establish the laminate strength and failure modes.
Furthermore, differernt Coupon types with functioning electrical elements, including the heater layer, busbars and cables were produced in order to establish the material testing in WP6.
WP5:
In WP5, the static specimen heater mats were produced successfully implemented into the environmental demonstrators.
In addition, heater mat coupons for various tests were manufactured
WP6:
In WP6, structural testing of various test coupons is done. There were some failures in the bus bars as well as in the substrate materials, for this reason. the loads were revised and additional testing is performed. The endurance testing could be finished.
WP7:
The main works performed in WP7 was preliminary testing of the environmental prop rotor spin demonostrator as well as the static testing on two demonstrators (mid-wing and root specimen) in the RTA Icing Wind tunnel.
WP8 & WP9:
During WP8 and WP9 the results from both environmental and structural testing were analized.
The heater layers developed in NO-ICE-ROTOR will not only be characterized by high energy efficiency and cost efficiency, but also by increased reliability and lower weight compared to conventional technologies.
The NextGenCTR, capable of generating lift and propulsion with two powered rotating rotors mounted at the ends of a fixed wing, will cover the market need of a civil aircraft that combines the VTOL capabilities of a rotorcraft with the speed and range of a conventional fixed-wing aircraft. The vehicle will expand the EU industry's existing portfolio of heavy multi-engine rotorcraft, providing high-speed, long-range and versatile operation.
Besides the Aviation industry, heater layer- based ice protection measures are of great importance also for all other means of transportation (cars, trains, and vessels), cooling and refrigeration units, for wind energy plants, for bridges, for antennas, and for transmission lines as well. Beyond numerous aeronautical applications, the heater layer technology proposed by NO-ICE-ROTOR has also been successfully applied in the wind energy domain. The further development of this technology pushed by NO-ICE-ROTOR will allow a cross-fertilization between aviation and other technological areas.
There are only very few icing wind tunnels worldwide, which are able to perform rotating tests like it was done in the No Ice Rotor project. The results and experience gained during preliminary testing of the rotating specimen are very helpful to improve future testing, as it showed, that it is a highly complex structural as well as aerodynamical issue. The spin rig test jig can be improved using the data and lessons learned during No Ice Rotor testing.
The NextGenCTR, capable of generating lift and propulsion with two powered rotating rotors mounted at the ends of a fixed wing, will cover the market need of a civil aircraft that combines the VTOL capabilities of a rotorcraft with the speed and range of a conventional fixed-wing aircraft. The vehicle will expand the EU industry's existing portfolio of heavy multi-engine rotorcraft, providing high-speed, long-range and versatile operation.
Besides the Aviation industry, heater layer- based ice protection measures are of great importance also for all other means of transportation (cars, trains, and vessels), cooling and refrigeration units, for wind energy plants, for bridges, for antennas, and for transmission lines as well. Beyond numerous aeronautical applications, the heater layer technology proposed by NO-ICE-ROTOR has also been successfully applied in the wind energy domain. The further development of this technology pushed by NO-ICE-ROTOR will allow a cross-fertilization between aviation and other technological areas.
There are only very few icing wind tunnels worldwide, which are able to perform rotating tests like it was done in the No Ice Rotor project. The results and experience gained during preliminary testing of the rotating specimen are very helpful to improve future testing, as it showed, that it is a highly complex structural as well as aerodynamical issue. The spin rig test jig can be improved using the data and lessons learned during No Ice Rotor testing.