Periodic Reporting for period 3 - EC2S (ENVIRONMENT CONTROL SECONDARY SYSTEM)
Reporting period: 2021-10-01 to 2023-03-31
The Environment control system plays a significant role in guaranteeing air quality and thermal comfort in the aircraft cabin. Nevertheless, standard ECS remains one of the main power consumer function in the aircraft. EC2S solution is to reduce the need of fresh flow from 70% to a much lower percentage by recycling and treating cabin air, downsizing the ECS system weight, fuel consumption, pollution and costs. The ambition is to design the first Air Recirculation System (named EC2S Environment Control Secondary System) by integrating the smartest Air treatment processes and Sensors and demonstrate its efficiency and certifiability on the CS2 regional aircraft ground demonstrator.
The main objectives of the project are :
• Objective 1: To define the architecture of the recirculation-air treatment system that regulates air treatment and optimizes the mix of outside and treated recirculated air, based upon airframer requirements.
• Objective 2: To map technologies in term of maturity and commercial availability for choice decision about technologies integration in the demonstrator
• Objective 3: Promote innovative technological bricks for specific air treatment functions.
• Objective 4: Build a demonstrator of an innovative Recirculation-air treating system in the REG Demonstrator.
The demonstrator was finally built with all scheduled functions. It was tested in lab and then in a cabin. Unfortunately, the cabin that was expected to be used was not available even after project extension so the final testing was done at Fraunhofer where a cabin (different size and position in aircraft) was available.
Results showed that filtration of VOC, PM and CO2 is working even if CO2 systems had limited perfomance due to smale scale device agreed by partner to validate the technology.
The main objectives of the project are :
• Objective 1: To define the architecture of the recirculation-air treatment system that regulates air treatment and optimizes the mix of outside and treated recirculated air, based upon airframer requirements.
• Objective 2: To map technologies in term of maturity and commercial availability for choice decision about technologies integration in the demonstrator
• Objective 3: Promote innovative technological bricks for specific air treatment functions.
• Objective 4: Build a demonstrator of an innovative Recirculation-air treating system in the REG Demonstrator.
The demonstrator was finally built with all scheduled functions. It was tested in lab and then in a cabin. Unfortunately, the cabin that was expected to be used was not available even after project extension so the final testing was done at Fraunhofer where a cabin (different size and position in aircraft) was available.
Results showed that filtration of VOC, PM and CO2 is working even if CO2 systems had limited perfomance due to smale scale device agreed by partner to validate the technology.
Based on a study for the state of the art on air quality in aircraft cabins, the architecture of the innovative recirculation EC2S loop has been defined. The conception study of the different filter elements has been done in parallel to the definition of the sensor & monitoring strategy. Hence, PDR of the system has been validated.
The design and sizing of the prototypes has been performed by simulations and definition of each technological brick has been based on experimental characterizations at the labscale:
- Innovative technology of PES (Electrostatic precipitation) of Particle matters
- Photocatalytic treatment of VOC
- Dimensioning & optimization of CO2 adsorbing filter & recirculation process.
Additionally, the sensors integration & development for miniaturization and fine tuning of sensitivity to targeted poluttants have been realized and the monitoring preliminary architecture has been validated commonly to the system PDR milestone.
During Period 2, the scale 1 demonstrator has been manufactured, with each techno bricks and ducting, and installed in Lab installation at Tera Environnement. First tests and trials have been performed at Tera Environnement and confirm the validity of the EC2S system.
Test campaign at demonstrator level have not been performed during this period due to Cleansky 2 misalignement for REG cabin ground demonstrator availability.
During period 3...
Alternative test campaign at Fraunhofer took place end of september 2022, confirming global efficiency of the system.
Regarding the VOC filtration, under constant generation of VOC, VOC decrease seems to be around 15% with mixed fresh air & recirculated air. When stopping VOC generation, VOC reduction reaches up to 85% in 1h.
Regarding PM filtration, under constant generation of PM, PM decrease seems to be around 30% with mixed fresh air & recirculated air. PM decrease is then >90% in 1h when stopping PM generation (considering particle size from 2,5nm up to 20µm).
As far as CO2 filtration is concerned, filtration efficiency is low when we maintain CO2 generation, but this was expected as the system was designed at a small-scale level, simply to validate the technology used. Nevertheless, as soon as we stop generating CO2, efficiency increases and enables to reach atmospheric CO2 concentration within half an hour.
Concerning exploitation & dissemination, several posts and article have been published during the project on social media and also on internet website of HUTCHINSON. A scientific article has been published by CEA in february 2022 in Indoor Air Journal, focusing on particle filtration using electrostatic precipitation technology versus classical mechanical filtration. In addition, CEA has particitpated to an international conference NanoSAFE in 2020.
Concerning exploitation, Tera Sensors is intended to produce and sell new type of particle sensor developped in this project.
The design and sizing of the prototypes has been performed by simulations and definition of each technological brick has been based on experimental characterizations at the labscale:
- Innovative technology of PES (Electrostatic precipitation) of Particle matters
- Photocatalytic treatment of VOC
- Dimensioning & optimization of CO2 adsorbing filter & recirculation process.
Additionally, the sensors integration & development for miniaturization and fine tuning of sensitivity to targeted poluttants have been realized and the monitoring preliminary architecture has been validated commonly to the system PDR milestone.
During Period 2, the scale 1 demonstrator has been manufactured, with each techno bricks and ducting, and installed in Lab installation at Tera Environnement. First tests and trials have been performed at Tera Environnement and confirm the validity of the EC2S system.
Test campaign at demonstrator level have not been performed during this period due to Cleansky 2 misalignement for REG cabin ground demonstrator availability.
During period 3...
Alternative test campaign at Fraunhofer took place end of september 2022, confirming global efficiency of the system.
Regarding the VOC filtration, under constant generation of VOC, VOC decrease seems to be around 15% with mixed fresh air & recirculated air. When stopping VOC generation, VOC reduction reaches up to 85% in 1h.
Regarding PM filtration, under constant generation of PM, PM decrease seems to be around 30% with mixed fresh air & recirculated air. PM decrease is then >90% in 1h when stopping PM generation (considering particle size from 2,5nm up to 20µm).
As far as CO2 filtration is concerned, filtration efficiency is low when we maintain CO2 generation, but this was expected as the system was designed at a small-scale level, simply to validate the technology used. Nevertheless, as soon as we stop generating CO2, efficiency increases and enables to reach atmospheric CO2 concentration within half an hour.
Concerning exploitation & dissemination, several posts and article have been published during the project on social media and also on internet website of HUTCHINSON. A scientific article has been published by CEA in february 2022 in Indoor Air Journal, focusing on particle filtration using electrostatic precipitation technology versus classical mechanical filtration. In addition, CEA has particitpated to an international conference NanoSAFE in 2020.
Concerning exploitation, Tera Sensors is intended to produce and sell new type of particle sensor developped in this project.
A very innovative Air Recirculation System (named EC2S Environment Control Secondary System) has been developed and designed by integrating the smartest Air treatment processes and Sensors and demonstrate its efficiency and certifiability on the CS2 regional aircraft ground demonstrator. Three key elements are integrated into the recirculation loop: filtration of particle matters by innovative electrostatic precipitation (ESP); filtration & treatment of CO2 and filtration & treatment of VOC by photocatalytic process. Based on the very low pressure drop performed by PES Filtration of PM, the global pressure drop shown by the complete system is similar to a standard HEPA system. Additionally, the recirculation loop is instrumented with selective miniaturized sensoring systems to monitor air quality on PM, CO2, VOC but also CO levels.
Hence, EC2S demonstrate an unprecedented set of technologies in order to reach higher premium level of filtration to improve the recirculation of air in the cabin.
By consequence the EC2S project offers improved monitoring of cabin air quality while opening to fuel consumption & CO2 emissions gains by offering more flexibility on recirculation phases during key energy demanding flight phases.
Performances were measured at Fraunhofer using their current cabin aircraft test bench, instead of REG cabin ground demonstrator (not yet available) and confirm ability to reduce up to 85% VOCs concentration and more than 90% of particle concentration in certain conditions
Nevertheless, a gross estimation of fuel consumption reduction, using hypothesis very dependant on the aircraft (architecture, consumption, operational contitions...) in a standard 80min duration flight, led to a possible saving around 0.3% of the total fuel amount needed per mission, in a standard 80min duration flight considering a reduction of almost 50% of the bleed-air flow rate during 20mn of the flight descent phase.This is less than initial expectation of the project but has to be recalculated with accurate aircraft parameters to refine hypothesis.
Hence, EC2S demonstrate an unprecedented set of technologies in order to reach higher premium level of filtration to improve the recirculation of air in the cabin.
By consequence the EC2S project offers improved monitoring of cabin air quality while opening to fuel consumption & CO2 emissions gains by offering more flexibility on recirculation phases during key energy demanding flight phases.
Performances were measured at Fraunhofer using their current cabin aircraft test bench, instead of REG cabin ground demonstrator (not yet available) and confirm ability to reduce up to 85% VOCs concentration and more than 90% of particle concentration in certain conditions
Nevertheless, a gross estimation of fuel consumption reduction, using hypothesis very dependant on the aircraft (architecture, consumption, operational contitions...) in a standard 80min duration flight, led to a possible saving around 0.3% of the total fuel amount needed per mission, in a standard 80min duration flight considering a reduction of almost 50% of the bleed-air flow rate during 20mn of the flight descent phase.This is less than initial expectation of the project but has to be recalculated with accurate aircraft parameters to refine hypothesis.