SDM College of Engineering and Technology

About: SDM College of Engineering and Technology is a based out in . It is known for research contribution in the topics: Diesel fuel & Combustion. The organization has 350 authors who have published 351 publications receiving 2399 citations.

Study and tailoring of screen-printed resistive films for disposable strain gauges

Abstract: The present work aims at fabrication and characterization of the novel dispersion based piezoresistive strain gauges. The novelty of present work is in the material-set and technique used to synthesize the low-cost, graphite powder based composites of various proportions without the need for additional pre-treatment or functionalization. When filler and resins are properly formulated, they can be printed in variety of shapes over different substrates such as glass, acrylic, plastics (such as PVC, PDMS, PMMA, PET, PI), metal foils, paper etc. They may be of great interest to integrate mechanical, chemical or temperature sensing functions in many electronic circuits and devices. In the current work, the resistive composite dispersions are screen-printed on glass substrate to fabricate the strain gauges and to study their piezoresistive strain performance. Graphite particles in the powder are found to have irregular shape and size. Thickness of screen-printed films varies in the range 13–27 μm. Gauge factors ranging from 17 up to 70 is achieved for the strain gauges having satisfactory stability, linearity and repeatability. The variation in GF is found to be less than 2%. Maximum hysteresis and nonlinearity were observed to be less than 2% FSO (Full Scale Output). Repeatability is found to be minimum 98%. The dispersion composition is tuned to obtain a better sensitivity. Regarding temperature effects, all the strain gauge samples exhibited a negative value of TCR, lowest being -2 × 10−4 /oC. Graphite powder and printing ink are inexpensive and commercially-available. Also, technique used to fabricate strain gauges avoids high-end equipment and expensive clean room facilities. These devices are robust, easy to scale & pattern, safely disposable strain gauges with are fairly good performance fabricated at low cost. These features make them a good candidate for pressure sensors, weigh bridges, displacement sensors, crack sensors, strain sensors etc. The real time potential applications are in different sectors such as automotive, aerospace, biomedical, oceanography and industrial purposes.

Performance degradation issues of PV solar power plant

Abstract: P V solar power plants are planned to work for long time, monitoring of plant will ensure a safety and longterm operation. The photovoltaic system degradation of 10% per year in the year 1991 has reduced to 12% for 25 years due to modules manufactured after 2000. Some of the common and basic degradation issues in pv solar plants are discussed in this paper. The adequate maintenance is required for long term operations and increasing performance.

Production of renewable and sustainable fuel from Calliandra calothyrsus and its utilisation in compression ignition engines

Abstract: Alternative fuels have several advantages compared to fossil fuels as they are renewable, biodegradable, provide energy security, foreign exchange saving as well as help in addressing environmental concerns and socio-economic issues. Therefore, renewable fuels can be used predominantly as a fuel for transportation and for applications in power generation. Shaft power application is a key factor for economic growth and prosperity and depends crucially on the long-term availability of energy from sources that are affordable, accessible and environmentally friendly. In this context, the main objective of the present study was to implement the production of bioethanol from Calliandra calothyrsus, a potential lignocellulosic raw material for the cellulose-to-bioethanol conversion process that can be used as an alternative resource to starch- or sugar-containing feedstock. This study addresses a new pretreatment method known as hydrothermal explosion using C. calothyrsus for ethanol production. The present stud...

Performance and emission characteristics of a CNG-Biodiesel dual fuel operation of a single cylinder four stroke CI engine

Abstract: The introducement of stringent emissions norms like Euro V and Euro VI is diverting the research to develop new technologies to reduce the engines exhaust emissions. Many researchers have adopted different techniques for lowering the tailpipe emissions from the engines where oxides of nitrogen (NOx) and smoke are mainly formed. In this study a diesel engine having single cylinder is converted into dual-fuel engine to operate with pilot injection of Diesel/biodiesel ethanol blend and Compressed natural gas (CNG). The engine was operated on both single fuel(SF) and dual fuel(DF) mode. The CNG was inducted into the inlet manifold through a gas carburettor on purpose designed for this application. The injection timings was optimized for CNG- biodiesel. The optimum injection timing was 27°BTDC. The pilot fuel injection pressure was maintained at 230 bar. Engine was operated with optimum Compression ratio of 17.5 and CNG flow rate was optimized and found to be 0.5 kg/h. The effect of CNG induction on combustion and emissions characteristics of a compression ignition engine with a dual fuel was studied and compared with single fuel operation. Comparative results revealing the effect of dual fuel combustion on the engine performance, combustion and exhaust emissions. Based on the performance, combustion and emission characteristics it is concluded that, use of CNG in the dual fuel mode in a diesel engine improves the performance and reduces the exhaust emissions from the engine except for HC and NOX emissions.

Roughness effect on squeeze film characteristics of porous circular plates lubricated with couple stress fluid

Abstract: This paper describes the combined effect of surface roughness and couple stress fluid on the performance characteristics of squeeze film lubrication between two circular plates. Using microcontinuum theory for the couple stress fluid and the Christensen stochastic model for the surface roughness, the modified Reynolds equation is derived by assuming the roughness asperity heights to be small compared to the film thickness. An eigenvalue problem involving Bessel functions enables analysis of the Reynolds equation. The expressions for mean pressure, load-carrying capacity, and squeeze film time are obtained for various probability distribution functions (pseudo normal, rectangular, and inverse square root distributions) that characterize the roughness of the lubricating surfaces. The influence of roughness and couple stress on bearing characteristics is presented in terms of the relative percentage in load for all these roughness patterns. © 2009 Begell House, Inc.