17-Mar-2021: New multifunctional heat sinks can dissipate heat from mechanical devices more efficiently
Indian Scientists have developed a multifunctional heat sink enabled by 3D printing, which can dissipate heat from mechanical devices at 50 percent enhanced rate compared to conventional sinks.
Existing approaches for heat exchanging and heat sink achieve different functions using dedicated units. In the new technology, multiple functions have been integrated together in a single unit. It can also be used to develop heat pipes, vapour chambers, heat exchangers and noise reducing heat sinks.
The technology enabled by 3D printing in combination with electroplating was developed to withstand load while dissipating heat by Dr Shankar Krishnan, Associate Professor Department of Mechanical Engineering, IIT Bombay with support from the Department of Science & Technology, Government of India under the ‘Make in India’ initiative. He has also filed a national patent on ‘noise reducing heat sinks’ and international patent will be applied subsequently. Experimental as well as computational validation has been carried out.
The technology is lightweight and can bear mechanical compressional loads, dissipate heat and absorb sound/noise. It can be used in the electronics cooling, electronics as well as power/cooling industry.
Based on open-literature survey, no such product exists in the market presently. Thermal management of electronics is a ten-billion-dollar market and is a potential beneficiary of this technology. Additionally, any fan-mounted heat exchanger can benefit from this development. Cost is a risk factor but partnering with high volume manufacturers will reduce this risk.
The technology is in third stage of Technology readiness levels (verification with experimental to verify that the concept works as expected) and Prof. Krishnan is in discussions with major semiconductor manufacturer or high volume manufacturing and will work further to enable compact noise (both broadband as well as tonal) reducing heat sinks.
3-Mar-2021: Indigenously designed and developed ‘Made in India’ spectrograph, commissioned on Devasthal Optical Telescope, can locate faint light from distant celestial objects
Indian Scientists have indigenously designed and developed a low-cost optical spectrograph that can locate sources of faint light from distant quasars and galaxies in a very young universe, regions around supermassive black-holes around the galaxies, and cosmic explosions.
Such spectroscopes were so far imported from abroad involved high costs. The ‘Made in India’ optical spectrograph named as Aries-Devasthal Faint Object Spectrograph & Camera (ADFOSC), indigenously designed and developed by Aryabhatta Research Institute of observational sciences (ARIES), Nainital, an autonomous institute of Department of Science and Technology (DST), Government of India, is about 2.5 times less costly compared to the imported ones and can locate sources of light with a photon-rate as low as about 1 photon per second.
The spectroscope, the largest of its kind among the existing astronomical spectrographs in the country, has been successfully commissioned on the 3.6-m Devasthal Optical Telescope (DOT), the largest in the country and in Asia, near Nainital Uttarakhand.
This instrument, a backbone of the 3.6-m DOT for observations of extremely faint celestial sources, uses a complex arrangement of several lenses made of special glasses, polished to better than 5-nanometer smoothness to produce sharp images of the celestial sky. Photons coming from distant celestial sources, collected by the telescope, are sorted into different colors by the spectrograph and are finally converted into electronic recordable signals using an in-house developed Charge-Coupled Device (CCD) camera cooled to an extremely low temperature of -120 0C. The total cost of this instrument is nearly Rs. 4 Crore.
Dr. Amitesh Omar, scientist at ARIES, led this project with a technical and scientific team, which together researched and developed various optical, mechanical, and electronics subsystems of the spectrograph and camera. The spectrograph is presently being used by astronomers from India and abroad to study distant quasars and galaxies in a very young universe, regions around supermassive black-holes around the galaxies, cosmic explosions like supernovae and highly energetic Gamma-ray bursts, young and massive stars, and faint dwarf galaxies.
“The indigenous efforts to build complex instruments like ADFOSC in India is an important step to become ‘Aatmanirbhar’ in the field of astronomy & astrophysics,” said Prof. Dipankar Banerjee, Director, ARIES.
Expertise from various national institutes, organizations, including the Indian Space Research Organization (ISRO) and some micro-small-medium-enterprises, were involved to review and build parts of the instrument serving as an example of effective collaboration. With this expertise, ARIES now plans to commission more complex instruments such as Spectro-polarimeter and high spectral resolution spectrograph on the 3.6-m Devasthal telescope in the near future.
17-Dec-2020: ARCI and IIT-H Scientists develop high-performance hybrid supercapacitors with novel electrode material
Scientists have developed a low-cost supercapacitor device with excellent capacitive retention with a novel electrode material they have synthesized, which can pave the way for the next generation high power-high energy storage devices.
Supercapacitors have gained considerable attention due to their high power density, long cycle life, and excellent capacity retention compared to their battery counterparts. Supercapacitors with high capacitance and excellent capacitive retention developed from low-cost fabrication techniques are the need of the hour, considering their potential utility in the commercial market.
Scientists at the International Advanced Research Center for Powder Metallurgy and New Materials (ARCI), an autonomous body of the Department of Science and Technology, Government of India in collaboration with IIT Hyderabad have developed a facile, scalable, and cost-effective electrochemical route to synthesize electrodes made of Nickel cobaltite (NiCo2O4) containing nanosheet structures with incorporated oxygen vacancies as an active material, for hybrid supercapacitors. These electrodes have been found to have excellent electrochemical performance.
Such hybrid supercapacitors combine the features of both conventional double layer supercapacitors and batteries and act as high power-high energy storage devices. However, it remains challenging to design pseudo capacitor devices with redox metal oxide (MO) materials with high porosity, which exhibit high capacitance and good cycle life. It is desirable to amend the intrinsic properties of the synthesized MO to enhance its conductivity, stability, and electrochemical activity.
Scientists at ARCI and IIT-H addressed these challenges and were successful in synthesizing NiCo2O4 nanostructured electrodes by a novel electrodeposition route. They also introduced an optimum number of oxygen vacancies by an environmentally benign chemical reduction process to make up for an active, positive electrode material for hybrid supercapacitor, as reported in their recent publication in the journal “Batteries & Supercaps". This could be an effective alternative to the existing carbon-based electrodes for supercapacitors to achieve high energy density.
An asymmetric supercapacitor device further fabricated by the research team, using porous carbon and NiCo2O4 electrodes exhibited excellent capacity retention and stability. The device could power an LED lamp and a DC fan, as shown in the figure.