WHAT ARE THE RECENT TECHNOLOGIES IN AVIATION TODAY?

 The following paper looks at the recent technology today in the aircraft engine. This paper acknowledges that fact that today we have many technological advancements in the aircraft engine. All these innovations are aimed at creating, more efficient and powerful engines that can be able to comfortably serve the need for power through efficient engine systems.

In this paper, the ELUBSYS aircraft engine lubrication system is identified as the most recent technology. This innovation comes after the previous innovation such as the use of the labyrinth seals have been used for more than 30 years expressing the length of time that this technology has taken in research and testing process. The jet engine lubrication system is an imperative part in the proper functioning of the engine. Proper lubrication not only increases the operating efficiency of the engine but as well increases the reliability and keeps the engine free from wear and tear. With most jet engines today rotating at speeds more than 18000 rotations per minute there is great need to increase their efficiency. Such a high level of rotation leads to the accumulation of temperature and pressure in the engine compartment. This creates a unique engine environment whereby the inside of the engine could end up reaching temperatures of more than 1000 degrees Celsius while the outside could be less than negative fifty degrees Celsius or even more.  As a result, the engines lose this lubricant to the outside environment contributing to environmental pollution. Additionally, this inefficiency also leads to inefficient fuel consumption which contributes to not only economic losses but also led to more environmental pollution by emitting more carbon dioxide which increases the ambient temperature in the air.

Therefore, we assess the use of the ELUBSYS lubrication technology which has been funded by the European Union.

The lubrication system is basically applicable on all jet engines. This innovation seeks to increase more oil and lubrication use efficiency as compared to the other former lubrication systems that have ever been used in the jet engines. Therefore, this recent technology is applicable to all jet engines for private, military, and commercial aircraft as well.

 A brief history of this new “Aerodynamic feature” and its development.

Jet engine lubrication systems have been an important part of the engine since the first use of the jet engine. The development of ELUBSYS lubrication technology was an indispensable aspect for several reasons. First there was a need to increase the speed of the jet and this would be achieved through increases rotations of the rotors and the proper functioning of the internal turbines.  To achieve speed therefore, there was a need to reduce the friction between any rotating surfaces within the engine compartment. The temperatures within the engine as well were very high and therefore to develop an optimum condition for the proper functioning of the engine there was a need to control these temperatures. As a result heat resistant lubricants were developed and applied successfully to the engine. The type of lubricants used has also been a matter of concern over the years and they too have seen this development. More viscous and heat tolerant lubricants have been developed to suite the nature of the jet engine.

The innovation discussed in this text is the ELUBSYS lubrication technology. This unlike the previous technologies that involved the spraying of the lubricant within the engine compartment, this technology incorporates the use of brushes. These brushes are apparently made of Kevlar fiber and the Carbon fiber which have been known to be both strong and heat resistant as well. Kevlar fiber and carbon fiber have almost similar chemical properties that enable them to withstand high level of tension and extremely high temperatures without being degraded. These brush seals are placed within the engine where they are used to lubricate the engine through a direct contact with the turbine shaft. They therefore offer a consistent lubrication to the shaft and the other engine parts without having to insert the lubricant on a periodic basis but rather on a continuous basis.

By being into contact with the rotating shaft, these Kevlar and carbon fiber brushes resist any leakage of the oil and as well maintaining a pressurized engine environment which is an important aspect in increasing the engines efficiency in power conversion and fuel use. The incoming air is this well pressurized thereby creating a perfect environment for generating enough thrust after the pressurized air is released through the rear jet engine nozzle.

The European Union joint project has seen the partnering of different individuals, aircraft engine manufacturing companies and governments.  The German company MTU and the France Company SNECMA have partnered to develop this new technology with even further commitment to developing an experimental house for the Kevlar and carbon fiber lubricating brushes. With this experimental housing unit, deep research has been carried on the technology in a bid to test its reliability and how well it rivals the existing technologies as well. This is due to the fact that if it cannot present an edge in the efficiency and safety as compared to the existing technology it lacks rationality.

The ELUBSYS jet engine lubrication system project was developed on the basis of the above discussed concerns. To achieve that, the MTU and SNECMA companies had to lay down objectives which were ideally critical to achieving their targets in making a better lubrication system.

ELUBSYS recognized that in making a reliable jet engine lubrication system, they needed to consider the properties of ideal engine oil that would work well with the system.  For turbine engines which operate at extreme temperatures between the inside and outside part, they would consider between the four types of engine oils which are graded on the basis of their use and chemical properties. The system required a slightly viscous oil since an oils ability to resist deformation depends on the temperature level and therefore coping with the high temperatures that would be generated by the carbon fiber brushes ability to aid air compression would exceed the normal engine temperatures.

There was a need to consider the flash point of the oil which is the temperature at which oil becomes combustible after combining with air. The Kevlar and carbon fiber brushes needed to have a high flash point. This is due to the higher temperatures expected in the jet engine’s ignition chamber. This would thus help to avoid fire in the oil system which would cause explosion and evaporation of the lubricant on the engine’s surfaces. Pressure resistance of the oils used was considered as well. The pressure resistance dictates the ability of oil to function as a lubricant. In the actual sense under high pressure, most lubricants are unable to withstand the pressure between the two bodies in contact leaving them to come into direct contact creating heat from friction and wearing out as a result.

With the need to establish the seals accompaniment engine oil, thermal stability too was important. This is apparently the ability of oil to withstand high or low temperatures without undergoing decomposition which would weaken its ability to minimize friction. This would go hand in hand with the oxidation resistance of the oil. With the sanction of the air which has oxygen from the air, considering lubricant oil that would not oxidize was vital. Oxidation of oils is further increased by temperatures as oil molecules become more energetic and reactive as well. Oils that would be able to avoid getting oxidized at the high temperatures would thus be more durable.

The brushes were a new technology to replace the labyrinth seals. However the other engine compartments and systems were not much affected. Venting system, sensors, scavenge pumps and the run line also. Pressure regulation would still be regulated by the full flow and the relieve valve systems. These systems would help in the lubrication of the other areas such as the rotor bearings through nozzles that would spray the oil.

First, the project aimed at creating better seals that would improve the efficiency of the engine thereby reducing the carbon dioxide emissions by target point of more than sixty percent reduction. The reduction in the emission would also facilitate the better conversion of air pressure in the engine by thrust power. This would this require the development of seals that reduced the air escape termed as air bleed from the engine chambers where the air is compressed and pressurized. Secondly, the project aimed at reducing the amount of oil that was rejected overboard by a target of sixty percent. This would reduce the consumption of oil which is ideally a non-renewable energy resource. The project relied on the basis that at the current levels, the pollution emanating from major commercial aircraft on average is 300ml per hour. Such an amount of pollution is considered high with regard to how international standards on fuel efficiency dictate. The use of better performing brush seals would thus create a better approach to reducing this pollution. Thirdly there was a need for a redesign that would see the use of less bulky lubrication compartments that would require less power to keep in space and occupy less space within the engine compartment as well. Lastly, there was a need to improve on the mechanisms of improving the engine oil quality. The lubrication system was therefore targeted to have better anti-coking capacity which would enable the engine take up higher temperatures inside for more time thus increasing its ability to convert energy from the oil.

Unlike the previously used labyrinth seals, the Kevlar, carbon fiber and metallic seals were used in the testing process to determine their fitness to the task and reliability as well. In the process of testing, their tolerance capabilities were measured while the air flow and the pressure of the internal engine compartment were analyzed to understand how each material responded when used to inject the lubricant into the engine. Several approaches in measuring the dynamics of fluid flows such as VOF, volume of fluids were used in the testing process. The flow was simulated across different environments that presented different lubrication needs to the jet engine to assess how suitable they were. The use of infra-red sensors, Quartz micro balance, Optical particle detectors and oil sensors was incorporated in ensuring that accurate test results emanated from the process.  

The lubrication systems that have played the role of boundary lubricants and coolants as well have evolved over many years. Ideally, this technology has seen developments over the years with each new innovation providing a better way to increase fuel efficiency and engine operating efficiency as well. Some of these innovations are therefore highlighted in this text.

Description of how this new “Aerodynamic feature” works.

The ELUBSYS technology works basically on the brushes ability to lubricate and control the air pressure in the engine chamber.  First by ensuring that there is a direct contact between the surface of the shaft and the Kevlar and the carbon fiber brushes, there is a more surface area increased towards direct contact making lubrication more efficient. The lubricants being used are thus better suited to the high level of heat environment through ensuring that they are viscous. By using brushes they are thus applied to the rotating parts well. The shaft in the combustion chamber and the rotor too are lubricated by this system. This ensures that even under the high level of rotation, the friction generated is minimal. This therefore increases the speed of the rotor while controlling wear and tear inside as well.

The ability of the Kevlar fiber and carbon fiber to withstand high temperatures and pressure make them suitable to clean the engine equipment thereby reducing carbon coking. Coking has in fact been a major issue whenever a jet engine is shut down. Carbon cocking clogs the engine compartments and nozzles thus reducing the engines efficiency. With the brush seals that are strong, the carbon deposits accumulation is reduced since they are in a constant rubbing process with the engine parts. The contact disk surfaces and the bristles have been found to be affected with the previous technology that involved labyrinth seals. These bristles prevent the oxidation of the seals through controlling the direct contact of gas fumes with the oil.

The bristles offer better mechanisms to contain pressure. Their closeness and ability to spread over a wide area makes them able to cover openings through which air escapes from the engine thus reducing the transmitted energy. These bristles as a result increase the temperature within the engine. More so their ability to withstand high temperatures makes them efficient as they do not decline in their functionality owing to the heat. The increased pressure is a good aspect of an efficient compression system which the engine serves. More energy is released as thrust air thus increasing the engine’s power and the aircrafts speed as well.

By creating the new aerodynamic engine technology, the jet engine has been able to increase in its efficiency and safety as well. Through the improved lubricating system the engine can now use less fuel by almost sixty percent less as compared to the preceding technologies.  Again, due to the increased ability of the engine to retain more pressure within the engine compartment due to the Kevlar and carbon brush seals ability to control the inflow of air, there is a massive reduction in the resulting lower fuel consumption that enables the jet to carry less fuel while flying.

As a result, the designers of jet fuel tanks can design tanks of lesser sizes which will help in the reduction of the weight being carried by the aircraft. As a result, the aircraft can carry more crucial matter such as cargo or people. Otherwise even the less fuel tank burden reduces the engines fuel consumption rate. More so this contributes positively in enhancing any future processes of designing and the redesigning of aircraft.

The oil and engine equipment are additionally made more efficient by this lubrication technology. By ensuring that those temperatures are controlled through the reduced friction within the engine equipment, the failure rate of the engine is reduced. It is worth noting here that the friction between the shirt and the chassis holding it creates wear and tear which further reduces the engines ability to generate power. The lubricant reduces this tear by creating a smoother surface for the two metal parts to move against each other.

Carbon dioxide emissions are controlled as well. Carbon dioxide is a greenhouse gas that is responsible for today’s environmental concerns such as global warming. Global warming has been a global concern of late due to its adverse effects that have created unpredictable weather patterns causing droughts and floods at unexpected times. In the previous labyrinth seals used in the lubrication systems, it was ideally hard to enhance further control of air pollution. However, with the Kevlar and the carbon fiber seals, the carbon dioxide emissions and other inert gases emitted during the combustion process are reduced by almost forty percent. By reducing the amount of jet engine fuel used, the amount of exhaust is reduced accordingly.

 Additionally the cost of repair and maintenance which is usually due to wear and tear owing to the friction inside the engine is reduced. All these benefits combined they add up to the economics of building better aircraft that is energy efficient, safer and less costly to repair and maintain.

Conclusion

In conclusion therefore, the new technology has been able to show an improved capability to respond to the identified objectives. In essence the need to have a more reliable and efficient lubricant systems have been achieved with the use of Kevlar and carbon fibers capability to withstand high temperatures, their durability and their physical nature that enables them to make seals that can lubricate engine components.

The lubricant system has been able to show excellent anti-coking capabilities thereby reducing the deposition of carbon compounds within the engine thus reducing maintenance and repair costs as well. Fuel has been more economically used presenting better approach in reducing air pollution and energy saving since this fuel is a non-renewable resource. These factors therefore contribute to reduced operating costs which form a significant part of the aircraft operating and maintenance costs. The consumption of air has been reduced by almost seventy percent while at the same time increasing the energy conversion capacity. The research and the innovation have contributed towards increasing the significance of brush seals and their usefulness in the bearing chambers which form an important component of the jet engine. The brush seals have therefore been found to be far more reliable and efficient than the conventional labyrinth seals.

Illustrations:

A cross section of the jet engine.

An illustration of the kelvar and carbon fiber bristles.

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