In Workpackage A the partner reports have given the consortium a better understanding of the many complex mechanisms at work in bearing chambers, gearboxes and vent lines. It has been shown that these mechanisms are controlled by many parameters, which include: air and oil flow rates and temperature, chamber geometry, rotational speed, and lubrication methods. These all affect power loss, heat generation, vent pipe flow composition and chamber heat transfer. The programme has established new correlation's for pressure losses in vent lines, bearing chambers and vent line heat transfer and gear windage. Together with the qualitative and quantitative rig data obtained it has given the partners the ability to develop design rules from a position of understanding. The two phase flow CFD code, developed during the programme, allows for the two phase flows in bearing chambers to be predicted, by tracking single sized particles.
In Workpackage B the feasibility study showed the possibility of significant savings in specific fuel consumption (sfc) and repair costs, with the introduction of lift augmented seals for bearing chamber sealing applications. The two seal manufactures showed it was possible for designs to be generated which would fit into available space. However both seal designs (axial lift augmented and air riding intershaft), which have been tested, have shown that further development work is required before the introduction of the seals into aeroengine applications. The development of the seal code will now allow the seal designs to be optimised more efficiently, and will reduce the time required for seal development.
This proposal is the result of a concerted effort by European manufactures in the fields of mechanical prime mover and power transmission machinery as well as associated component suppliers. The objective of the proposed work is to develop analytical design methods applicable to complex lubrication system phenomena and advanced seals technology. It is intended to carry out experimental and theoretical investigations in order to develop these methods. Two topics will be addressed:
A. Two phase air/oil flow and heat transfer;
B. Dynamic seals technology.
It is expected that the knowledge to be gained by applying modern experimental and theoretical techniques to these problems will lead to a major improvement in design capability within European manufacturing industries. This will provide the foundation for cost reductions and innovations necessary to maintain a competitive manufacturing base and to protect the environment. One example is the aero gas turbine industry which is potentially worth 80 billion ECU and where a wide range of technical improvements must be pursued to resist competitive pressure from other developed countries.
Funding SchemeCSC - Cost-sharing contracts
4041 Milmort (Herstal)
540 06 Thessaloniki
SA2 8PP Swansea