IIT-Madras and General Electric tie-up to build a next-gen combustor for small aircraft and helicopter engines.
IIT Madras and General Electric India Technology Centre (GEITC) are jointly developing a 3D printed combustor aimed at reducing weight and improving fuel efficiency in small aircraft and helicopter engines. Both organisations are designing the combustor – the burner in a gas turbine engine, with nearly one-tenth of the parts as compared to traditional engines.
The Rs 7.24 crore Uchhatar Avishkar Yojana (UAY) project is being carried out by the aerospace department at the Institute and is being funded by the government of India (75%) and GEITC (25%). “The fabricated combustor has only four parts whereas the same combustor, with conventional manufacturing, will have at least thirty parts,” said Prof SR Chakravarthy, Faculty In-charge, National Centre for Combustion Research – NCCRD at IIT Madras.
“The primary objective of this project is to reduce the length of the combustor, which will reduce its weight. It also reduces the fuel consumption of the engine,” he said. The engine could also be used in power generation. In larger aircraft, it could be used as part of an auxiliary power unit (APU), as well as for distributed/decentralised power generation as in backup gensets, or in remote locations, or along with hybrid solar/wind smart grid solutions.
While there have been several improved combustors designs recently, this project aims to further improve these metrics with a design that uses additive manufacturing technology and non-intrusive laser diagnostics. The project team has successfully completed testing three 8-cup full annular combustor configurations. The results show the feasibility of 30% reduction in length of a conventional rich burn combustor.
Currently, the team is focussing on the optical diagnostics experiments where laser diagnostics tools are being used to understand the flow physics inside the combustor. These results will help optimize the performance and to probe any further possibilities of length reduction, the professor said. The size and weight of the engine would be the same depending upon how the combustor is designed to fit into the rest of the engine. The weight savings, however, will be on the raw material of fabrication in additive manufacturing. This could lead to a substantial drop in weight, as much as 50% when compared to conventional combustors.
Further, Dr Chakravarthy said the additive manufacturing of the combustors which were tested for this project were outsourced to Indian suppliers. These suppliers, he said, were now capable of adapting additive techniques for geometries as complex as combustor domes and liner, which in turn would help in developing the country’s additive manufacturing infrastructure. A special feature of this project is that it marks the first time that a 3D printed full annular combustor was tested at actual turbine conditions in India. The lab, which is housed in the National Centre for Combustion Research and Development (NCCRD) at IIT-M also boasts of being the first in India to have a high pressure optically accessible combustor test rig and state of the art laser diagnostics tools under one roof.
IIT-M has an IP rights share with GEITC and expects GEITC to immediately use this in their product. Going forward, Dr Chakravarthy said that if GEITC is not absorbing the technology, for whatever reason, they have the first right of refusal after a lock-in period for IIT-M to commercialise the IP. Commercialization will be in the form of licensing to similar such engine houses as GEITC or to a start-up to develop a product that could be incubated by IIT-M itself.
