Abstract
A computational analysis was carried out on two different materials of turbine blades, namely Inconel MA754 and Nimonic 80A, in order to determine their structural and thermal properties at elevated temperatures. Long carbon fibers of uniform length were used and deposited at varying thicknesses ranging from 1 mm to 4 mm, on the top surface of turbine blades and then analyzed for its performance. It is seen that the carbon fibers (IM10) embedded in the super alloys drastically improve the load bearing parameters of the configurations being analyzed. The improvement in structural load carrying ability is a result of higher Young's modulus primarily. Subsequent analysis with higher volume fraction of the fibers indicated saturation of performance at about 70% volume fraction for 4 mm fibers and significant improvement beyond it for the 1 mm fibers. With improvement in the load bearing characteristics the blade with fibers embedded into a tube like structure at 3 sections were configured and A thermal analysis of the same underscores the effectiveness of the 4 mm fibers in undergoing much reduced principal strains than other configurations. This is seen to be a result of insulation of the top surface from increase in temperature, which significantly reduces the thermal expansion, especially at the free end. This is in contrast to other configurations, where the low volume fraction of fibers resulted in high principal strain.
Highlights
The crux of modern day aircraft propulsive performance is related to ideas of clean combustion, higher operating pressures, and temperatures for turbines
The effect of larger carbon fibers, which eventually lead to larger volume fraction of the surface is more drastic, with an order of magnitude lower stress and strains, associated with both principal stresses as well as shear stress
Once the idea of higher volume fraction of carbon fibers, especially in the top surface proving to be effective in withstanding higher loads, and in reducing principal strains, we explore the effect of increasing the volume fraction of carbon fibers on top compared to the overall volume
Summary
The crux of modern day aircraft propulsive performance is related to ideas of clean combustion, higher operating pressures, and temperatures for turbines. Among the forementioned ideas, the role of higher operating turbine temperatures has probably the most impact on the success of the other two ideas. This is evident from the compressor, that derives its work from turbine and is intrinsically linked. Cleaner combustion is constrained by the turbine inlet temperature to a certain degree, and the whole geometry of combustion chamber liners and dilution holes are associated with the choice of materials for turbine blades. The two widely approached ideas on improving turbine operating temperature are -1. Development of materials that can withstand high temperatures, albeit with the aid of cooling
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: American Journal of Mechanical and Materials Engineering
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
