摘要 :
Electric propulsion systems are considered as one possibility to reach the ambitious goals of the European Union’s Flightpath 2050 with regards to greenhouse gas emissions and noise. It has been claimed in several publications th...
展开
Electric propulsion systems are considered as one possibility to reach the ambitious goals of the European Union’s Flightpath 2050 with regards to greenhouse gas emissions and noise. It has been claimed in several publications that Distributed Electric Propulsion (DEP) offers significant improvement in aerodynamic efficiency and thus a reduction in structural weight of the wing and noise emissions as well as additional degrees of freedom concerning flight control. To not outweigh those advantages by heavier drivetrains, the components within the electric propulsion system have to be extremely lightweight, efficient and reliable at the same time. The German nationally funded project SynergIE evaluates DEP for a 70 PAX regional reference aircaft with two (SE-2), six (DEP-6) and twelve (DEP-12) propulsion units with a turbo-electric drivetrain layout. This study aims to quantify the effect on the specific block fuel consumption for the different numbers of propulsors based on Top Level Aircraft Requirements (TLARs). The approach contains a coupled electric drivetrain system model which is based on physically derived, analytical models for each component linking specific subdomains, e.g., electromagnetics, structural mechanics and thermal analysis. A genetic algorithm is applied to optimise the key performance indicators (KPIs) of the electric system, before the results are fed back to the aircraft sizing process. It has been identified that constraints such as installation space or architectural decisions such as the number of propulsors have significant influence on the drivetrain weight and efficiency and interact with the whole aircraft sizing process, esp. with reference to nacelle weight and drag and thus the block fuel consumption. The study shows that the DEP-6 and DEP-12 project aircraft both have a potential of reducing the specific block fuel consumption by approx. 4.2 % and 5.8 % respectively in case of direct driven propellers, while for a geared-drive scenario a total reduction of up to 7.6 % in case of DEP-6 and 8.5 % in case of DEP-12 is possible, all compared to the direct-driven baseline (BSL) aircraft SE-2.
收起
摘要 :
Electric propulsion systems are considered as one possibility to reach the ambitious goals of the European Union’s Flightpath 2050 with regards to greenhouse gas emissions and noise. It has been claimed in several publications th...
展开
Electric propulsion systems are considered as one possibility to reach the ambitious goals of the European Union’s Flightpath 2050 with regards to greenhouse gas emissions and noise. It has been claimed in several publications that Distributed Electric Propulsion (DEP) offers significant improvement in aerodynamic efficiency and thus a reduction in structural weight of the wing and noise emissions as well as additional degrees of freedom concerning flight control. To not outweigh those advantages by heavier drivetrains, the components within the electric propulsion system have to be extremely lightweight, efficient and reliable at the same time. The German nationally funded project SynergIE evaluates DEP for a 70 PAX regional reference aircaft with two (SE-2), six (DEP-6) and twelve (DEP-12) propulsion units with a turbo-electric drivetrain layout. This study aims to quantify the effect on the specific block fuel consumption for the different numbers of propulsors based on Top Level Aircraft Requirements (TLARs). The approach contains a coupled electric drivetrain system model which is based on physically derived, analytical models for each component linking specific subdomains, e.g., electromagnetics, structural mechanics and thermal analysis. A genetic algorithm is applied to optimise the key performance indicators (KPIs) of the electric system, before the results are fed back to the aircraft sizing process. It has been identified that constraints such as installation space or architectural decisions such as the number of propulsors have significant influence on the drivetrain weight and efficiency and interact with the whole aircraft sizing process, esp. with reference to nacelle weight and drag and thus the block fuel consumption. The study shows that the DEP-6 and DEP-12 project aircraft both have a potential of reducing the specific block fuel consumption by approx. 4.2 % and 5.8 % respectively in case of direct driven propellers, while for a geared-drive scenario a total reduction of up to 7.6 % in case of DEP-6 and 8.5 % in case of DEP-12 is possible, all compared to the direct-driven baseline (BSL) aircraft SE-2.
收起
摘要 :
A lack of guidance exists for the tuning of motion platforms for rotorcraft flight simulation. This is despite the widespread use of systems worldwide and the requirement for their use for the highest level of training simulators....
展开
A lack of guidance exists for the tuning of motion platforms for rotorcraft flight simulation. This is despite the widespread use of systems worldwide and the requirement for their use for the highest level of training simulators. In this paper, the state-of-the-art fixed-wing objective tuning methodology, the Objective Motion Cueing Test (OMCT), is applied to a typical rotorcraft manoeuvre. The goal of the investigation is to determine whether pilots observe negative transfer of training (ToT) when using different motion configurations. Results show large changes in subjective opinion following modifications to motion parameters. Pilot opinion was generally in disagreement with current fixed-wing 'fidelity boundaries'. The largest difference observed was the task performance time, which was found to increase with motion amplitude. Changes in objective performance parameters were smaller than subjective results. Results show? the requirement for additional efforts to define suitable rotorcraft fidelity boundaries to eliminate negative ToT.
收起
摘要 :
A lack of guidance exists for the tuning of motion platforms for rotorcraft flight simulation. This is despite the widespread use of systems worldwide and the requirement for their use for the highest level of training simulators....
展开
A lack of guidance exists for the tuning of motion platforms for rotorcraft flight simulation. This is despite the widespread use of systems worldwide and the requirement for their use for the highest level of training simulators. In this paper, the state-of-the-art fixed-wing objective tuning methodology, the Objective Motion Cueing Test (OMCT), is applied to a typical rotorcraft manoeuvre. The goal of the investigation is to determine whether pilots observe negative transfer of training (ToT) when using different motion configurations. Results show large changes in subjective opinion following modifications to motion parameters. Pilot opinion was generally in disagreement with current fixed-wing 'fidelity boundaries'. The largest difference observed was the task performance time, which was found to increase with motion amplitude. Changes in objective performance parameters were smaller than subjective results. Results show? the requirement for additional efforts to define suitable rotorcraft fidelity boundaries to eliminate negative ToT.
收起
摘要 :
When tuning motion platforms, subjective opinion is usually regarded as sufficient for most applications, as it provides verification that no false cueing, and subsequently no negative training occurs. However, often systems are f...
展开
When tuning motion platforms, subjective opinion is usually regarded as sufficient for most applications, as it provides verification that no false cueing, and subsequently no negative training occurs. However, often systems are far from optimal for their specific purpose. This paper presents a new method to objectively tune simulation motion platforms. Enhancement of motion utilization is shown through both theoretical appraisal of motion usage and through subjective pilot assessments. The function used to tune the motion parameters is presented, and shows promise for a standard process for the continuous, and application based tuning, of future rotorcraft motion platforms.
收起
摘要 :
When tuning motion platforms, subjective opinion is usually regarded as sufficient for most applications, as it provides verification that no false cueing, and subsequently no negative training occurs. However, often systems are f...
展开
When tuning motion platforms, subjective opinion is usually regarded as sufficient for most applications, as it provides verification that no false cueing, and subsequently no negative training occurs. However, often systems are far from optimal for their specific purpose. This paper presents a new method to objectively tune simulation motion platforms. Enhancement of motion utilization is shown through both theoretical appraisal of motion usage and through subjective pilot assessments. The function used to tune the motion parameters is presented, and shows promise for a standard process for the continuous, and application based tuning, of future rotorcraft motion platforms.
收起
摘要 :
The use of active inceptor systems allows for control of the aircraft even during mechanical failures within the control inceptor. For the specific case of isometric failure, whereby the inceptor 'freezes' in position, a virtual f...
展开
The use of active inceptor systems allows for control of the aircraft even during mechanical failures within the control inceptor. For the specific case of isometric failure, whereby the inceptor 'freezes' in position, a virtual force-displacement model is used to continue to provide control input. Experimental flight tests using the German Aerospace Center's (DLR) research helicopter (ACT/FHS) has shown the potential to encounter pilot-induced oscillation (PIO) tendencies when flying using this mode. This paper presents results from a simulation campaign undertaken to confirm whether PIOs may be exposed through this use of control and/or the resultant severity. The results show that the isometric failure mode caused severe PIOs. Unacceptable failure characteristics were reported by all four pilots. The use of offline prediction tools showed the incipience of PIO. It is recommended that specific PIO investigations are undertaken during the evaluation of active inceptor failure modes.
收起
摘要 :
The use of active inceptor systems allows for control of the aircraft even during mechanical failures within the control inceptor. For the specific case of isometric failure, whereby the inceptor 'freezes' in position, a virtual f...
展开
The use of active inceptor systems allows for control of the aircraft even during mechanical failures within the control inceptor. For the specific case of isometric failure, whereby the inceptor 'freezes' in position, a virtual force-displacement model is used to continue to provide control input. Experimental flight tests using the German Aerospace Center's (DLR) research helicopter (ACT/FHS) has shown the potential to encounter pilot-induced oscillation (PIO) tendencies when flying using this mode. This paper presents results from a simulation campaign undertaken to confirm whether PIOs may be exposed through this use of control and/or the resultant severity. The results show that the isometric failure mode caused severe PIOs. Unacceptable failure characteristics were reported by all four pilots. The use of offline prediction tools showed the incipience of PIO. It is recommended that specific PIO investigations are undertaken during the evaluation of active inceptor failure modes.
收起
摘要 :
The paper discusses recent results of flight tests performed during the NIAG DVE flight test campaign in Manching, Germany and Alpnach. Switzerland in February 2017. The Hensoldt DVE system SFERION® was mounted on two platforms i...
展开
The paper discusses recent results of flight tests performed during the NIAG DVE flight test campaign in Manching, Germany and Alpnach. Switzerland in February 2017. The Hensoldt DVE system SFERION® was mounted on two platforms in two different configurations. The first platform was a Swiss Airforce EC635 on which SFERION® was mounted with the SferiSense® 500 LiDAR. SFERION® displayed 3D conformal symbology for in-flight and landing support purposes. The second platform was the German DLR owned and operated EC135 ACT/FHS test helicopter. There a system using SferiSense® 300 LiDAR data supported the pilot during the final approach to a hover point by providing flight path monitoring, guidance and updating. In both systems the information was displayed on head-tracked helmet mounted displays (HMDs).Specific LiDAR performance in the encountered real-life DVE conditions is discussed. A number of pilots flew the respective systems and results of pilot assessments on workload and capabilities as well as conclusions for the SFERION® system are discussed.
收起
摘要 :
The paper discusses recent results of flight tests performed during the NIAG DVE flight test campaign in Manching, Germany and Alpnach. Switzerland in February 2017. The Hensoldt DVE system SFERION? was mounted on two platforms in...
展开
The paper discusses recent results of flight tests performed during the NIAG DVE flight test campaign in Manching, Germany and Alpnach. Switzerland in February 2017. The Hensoldt DVE system SFERION? was mounted on two platforms in two different configurations. The first platform was a Swiss Airforce EC635 on which SFERION? was mounted with the SferiSense? 500 LiDAR. SFERION? displayed 3D conformal symbology for in-flight and landing support purposes. The second platform was the German DLR owned and operated EC135 ACT/FHS test helicopter. There a system using SferiSense? 300 LiDAR data supported the pilot during the final approach to a hover point by providing flight path monitoring, guidance and updating. In both systems the information was displayed on head-tracked helmet mounted displays (HMDs).Specific LiDAR performance in the encountered real-life DVE conditions is discussed. A number of pilots flew the respective systems and results of pilot assessments on workload and capabilities as well as conclusions for the SFERION? system are discussed.
收起
原文获取