Chandra Shakher received Master of Technology in Applied Optics from the Indian Institute of Technology Delhi in 1976 and Ph.D. from the Indian Institute of Technology Madras in 1980. He worked as Scientist at Central Scientific Instruments Organization, Chandigarh from Nov.1979 to May 1983. In May 1983 he joined Bharat Heavy Electricals Limited, Hyderabad, an industry dedicated for the manufacturing of power generating equipments, as Deputy Manager. In March1989, he joined Instrument Design Development Centre (IDDC) of the Indian Institute of Technology, Delhi (IIT Delhi) as Chief Design Engineer and subsequently in 1995 he was elevated to the position of Professor. For two academic sessions (2002-2004) he was on lien from IIT Delhi and joined as the Director of National Institute of Technology Hamirpur (Himanchal Pradesh), India. Currently he is professor at IDDC, IIT Delhi. He has handled a large number of research projects and industrial consultancies. He has been an invited fellow of AIST, Japan and JSPS, Japan. His research interests include scientific and industrial applications of holographic interferometry, laser speckles, digital holography, fiber optic sensors, optical coherence tomography and laser based instrumentation. He has published 84 research papers in international reviewed journals and 45 papers in the proceedings of international conferences. He holds four patents. He is a fellow of the Indian National Academy of Engineering and SPIE. He received Institute Outstanding Faculty Award for 1994-1995, for significant research and development work in holographic techniques and laser based systems and NRDC Independence Day Award 1993 for development of laser based alignment system for electrical power machinery.
“Interferometric techniques for measurement of temperture and temperature profile of gaseous flames”
In this talk, interferometric techniques - like Talbot interferometry, speckle shearing interferometry, Lau phase interferometry, lateral shearing interferometry and digital holographic interferometry - for measurement of temperature and temperature profile of gaseous flames from burners are discussed.
In compressible flows the density varies with velocity sufficiently to give measurable results in the variation of the refractive index, and the temperature can be inferred from this. For incompressible flows, such as free convection, where the velocity is relatively low, the density and hence refractive index are directly related to temperature. Methods for observing this density variation include schlieren, shadowgraph, and interferometric techniques.
Interferometric methods allow to quantify the spatial and temporal distribution of index of refraction of transparent fluids. Once the index of refraction distribution is known, depending on the experiment, it can be related to fluid properties of interest, such as density, temperature or concentration of diffusing substance.