Tejas AsharAerospace Engineering BEng
Design and Fabrication of a Schlieren System
Schlieren photography is a common name given to the optical technique of capturing changes in density of transparent media. It is possible that, with the aid of simple tools and advanced engineering, Schlieren technique will enable us to visualise the combustion process of various fuels in a constant volume combustion chamber. Detailed historical and current data has been analysed on Schlieren systems, which has allowed us to design and build a system which can be easily shaped into a desired configuration with little modification. Such a system is built and then developed around constant volume combustion chamber to visualise the combustion process qualitatively. These setups are tested with flames of two different fuels acting as the Schliere objects of the system. The flexible system is briefly tested with different types of optics to generate the limits of the dimensions of the system. Rigorous research is conducted on manipulation of sensitivity of the system by introducing a variety of filters in the focal plane of the Schlieren head. A simple knife edge proves to be the optimum choice in order to attain control over the complete contrasting effect of the Schlieren images.