Chandigarh University

About: Chandigarh University is a education organization based out in Mohali, India. It is known for research contribution in the topics: Materials science & Computer science. The organization has 1358 authors who have published 2104 publications receiving 10050 citations.

Experimental investigation of heat transfer and exergy loss in heat exchanger with air bubble injection technique

Abstract: The main aim of this study is to evaluate thermal performance and exergy analysis of a shell-and-tube heat exchanger with a new technique called air bubble injection. The study has been carried out with different parameters such as flow rate, fluid inlet temperature, and different air injection techniques. The air has been injected at different locations such as the inlet of pipe, throughout the pipe, and in the outer pipe of the heat exchanger. Based on the results, the performance of the heat exchanger enhances with an increase in the flow rate and the fluid inlet temperature. The exergy loss and dimensionless exergy loss increase with a rise in the flow rate. The maximum and dimensionless exergy losses are obtained at a maximum flow rate of 3.5 l min−1. With the air bubble injection in the heat exchanger, it has been observed that the temperature difference increases, which leads to an increase in the exergy loss. The injecting air bubbles throughout the tube section shows that minimum dimensionless exergy is 27.49% concerning no air injection.

A Comprehensive Study on Computational Pansharpening Techniques for Remote Sensing Images

Abstract: Real-time remote sensing imaging systems require high spatial resolution multispectral images. However, the remote sensing images obtained from a single satellite sensor do not provide a significant amount of information. Therefore, pansharpening techniques are desirable to provide high spatial resolution multispectral images. The hyperspectral pansharpening techniques are used to fuse the hyperspectral (HS) and the panchromatic (PAN) images to obtain an HS image with a significant amount of spatial and spectral information. The main objective of this paper is to provide a comprehensive review of the pansharpening techniques. Various categories of pansharpening techniques are also discussed. This paper provides three different summaries: initially, the conceptual aspects of pansharpening techniques are discussed. Thereafter, the comparative analyses are performed to evaluate the benefits and shortcomings of the existing pansharpening techniques. Finally, challenges and opportunities for future research in the field of pansharpening are discussed.

Virtual Grid based energy efficient mobile sink routing algorithm for WSN

Abstract: In Wireless Sensor Network, sensor nodes are low powered and small devices mainly deployed in critical regions. Due to their energy constraint issues, many routing algorithms have been developed for efficient forwarding of data for minimizing energy consumption. Considering the static sink, nodes near the sink will have more load for routing data, therefore sink has been made as mobile. Now the sink can itself moves to the sensor node or leader node for collecting data as sink can be charged with high energy. Moreover sensor nodes deployed in battlefields, hills and similar risky areas are difficult to monitor for their energy issues. So the concept of grid arises. Now the sensor network can be constructed as logical grids of uniform size and data aggregation can be done using energy efficient routing. The proposed algorithm is an enhanced form of VGDRA algorithm which is grid based routing algorithm but lacks the concept of estimating energy on the basis of distance. In the proposed algorithm, sensor network is divided into logical grids of k-cells and a Cell Header (CH) is elected among each cell that acts as leader to cluster. The algorithm proves to be efficient in terms of energy by minimizing route construction cost considering shortest distance to sink.

Microstructural analysis and hot corrosion behavior of HVOF-sprayed Ni–22Cr–10Al–1Y and Ni–22Cr–10Al–1Y–SiC (N) coatings on ASTM-SA213-T22 steel

Abstract: The present paper deals with the investigation of microstructure and high-temperature hot corrosion behavior of high-velocity oxy fuel (HVOF)-produced coatings. Two powder coating compositions, namely, Ni22Cr10Al1Y alloy powder and Ni22Cr10Al1Y (80wt%; microsized)-silicon carbide (SiC) (20wt%; nano (N)) powder, were deposited on a T-22 boiler tube steel. The hot corrosion behavior of bare and coated steels was tested at 900°C for 50 cycles in Na2SO4-60wt%V2O5 molten-salt environment. The kinetics of corrosion was established with weight change measurements after each cycle. The microporosity and microhardness of the as-coated samples have been reported. The X-ray diffraction, field emission-scanning electron microscopy/energy dispersive spectroscopy, and X-ray mapping characterization techniques have been utilized for structural analysis of the as-coated and hot-corroded samples. The results showed that both coatings were deposited with a porosity less than 2%. Both coated samples revealed the development of harder surfaces than the substrate. During hot corrosion testing, the bare T22 steel showed an accelerated corrosion in comparison with its coated counterparts. The HVOF-sprayed coatings were befitted effectively by maintaining their adherence during testing. The Ni22Cr10Al1Y-20wt%SiC (N) composite coating was more effective than the Ni-22Cr-10Al-1Y coating against corrosion in the high-temperature fluxing process.