| Abstract |
It is known that business needs are placing an ever increasing demand on the aeronautics industry to develop and manufacture aircraft at lower costs, with improved flight capabilities and a reduced impact on the environment. Hence, a primary objective for the aerospace industry is to offer products that not only meet the operating criteria but also significantly reduce the direct operating costs.
Furthermore, research effort with respect to an improved understanding of the flow physics around fuselage / tail combinations remained limited, as investigations naturally concentrated on the wing and its interference with the fuselage. However, a successful design approach towards the development of modern transport aircraft has to include the empennage as well. This has to be seen in the light of the fact that performance guarantees for future aircraft have to be granted earlier and with higher accuracy as compared to former developments.
Therefore, In order to cope with the current aeronautics industrial needs which for sure are different from what was relevant in the past, a new integrative approach is proposed, closing the gap between the current classical empennage design and the possible future unconventional empennage design (an example is the work performed in the European NEFA project). This can be achieved bringing the current tail designs to its utmost level of optimised performance and highly efficient empennage control surfaces (elevator and rudder).
Thus, the improvements to be achieved by REMFI focus on three main aspects, the enhanced understanding of the tail flow physics, improved computational predictions for fuselage/tail design and analysis and improved experimental capabilities and measuring techniques for tail flows.
This aims at providing means to:
-Increase the empennage aerodynamic efficiency and reduce loads
-Improve flight safety
-Improved empennage performance and weight for optimised gaps effects, including Reynolds number effects
-Investigate sting mounting effects on empennage wind tunnel measurements
-Enhance the current scaling methodologies to free-flight conditions
-Reduce fuel burn (this has a positive effect on energy saving and reduction of emissions to the environment)
-Novel design concepts for integrated fuselage / empennage designs with regard to significant interaction between rear fuselage and belly fairing
-Investigate novel flow control devices (speed brakes) on fuselage and vertical tail
-Shorten the design cycle
-Reduce the cost of the aerodynamic design of tail and fuselage
-Reduce the maintenance costs
The following major achievements are expected:
-Fully optimised empennage design with highly efficient control surfaces with respect to:
·Elevator / rudder fuselage gaps effects on empennage performance (efficiency and hinge moments)
·Transition effects on empennage performance, efficiency and hinge moments
-Improved live-rear-end measuring technique including comprehensive understanding of:
·Split gap effects on the empennage measurement accuracy
·Twin-sting mount arrangement effects on empennage measurement accuracy
-Comprehensive set of tail-specific data advanced aircraft type configurations containing detailed flow field information up to full-scale Reynolds numbers
-Advanced CFD tools for industrial application with specific guidelines for empennage flow simulation
-Improved knowledge on scale effects up to true flight Reynolds numbers
-New and innovative designs for integrated fuselage and empennage including belly fairing
-Drag increasing devices for steep descend to reduce noise impac |
