Gear fault diagnosis using vibration signals based on decision tree assisted intelligent controllers

Gears are one of the most widely used elements in rotary machines for transmitting power and torque. The system is subjected to variable speed and torque which leads to faults in gears. This paper presents two different online condition monitoring systems using fuzzy and artificial neural network (ANN) controller for the fault diagnosis of spur gear. This work is conceived as pattern recognition problem and it consists of four main phases: viz. feature extraction, feature selection using C4.5 algorithm, training of fuzzy and ANN controllers with the selected features. Under feature extraction, statistical features like skewness, standard deviation, variance, root mean square (RMS) value, kurtosis, range, minimum value, maximum value, sum, median and crest factor are considered as features of the signal in the fault diagnostics. These features are extracted from vibration signals of time domain obtained from the experimental setup through a piezoelectric sensor. The vibration signals from the sensor are captured for normal tooth, wear tooth, broken tooth and broken tooth under loading conditions. The controllers are built and tested with representative data and the performance is also discussed

Role of biodiesel with nanoadditives in port owned trucks and other vehicles for emission reduction

Biodiesel is presently available all over the world and can be produced from several types of biomass. Biodiesel fuels are gaining more and more importance as an attractive alternate fuel in various transport sectors due to their renewable nature and lower pollution impact. However, the ports and the shipping sector are still in the early stage of orientation towards biofuels. In the present work, an experimental investigation on the use of diesterol blend (a mixture of diesel, ethanol with biodiesel) with cerium oxide as a nanoadditive (D80JBD15E4S1 + cerium oxide) in a compression ignition engine is performed to assess the emission characteristics. The results reveal that the presence of the cerium oxide nanoparticle changes the reaction patterns and heat transfer rate that reduces both the CO and CO2 percentage concentration in the exhaust gas appreciably. Further, the reduction in CO2 emission in the port of Chennai is quantified considering the replacement of neat diesel with those of modified diesel blend in port owned trucks and vehicles

GHG emission accounting and mitigation strategies to reduce the carbon footprint in conventional port activities – a case of the Port of Chennai

Ports as an industry account for ∼3% of the total greenhouse gas (GHG) emissions worldwide. The Port of Chennai, India, uses an enormous amount of electricity and diesel for intermodal transportation of goods and for other essential services. The inventory of GHG emissions in the Port of Chennai is made by accounting the various facilities of the port along with the housing colony and fishing harbor which come under the management of the Port of Chennai. Quantification of GHG emissions is made following the guidelines of the Intergovernmental Panel on Climate Change (IPCC) and World Port Climate Initiative (WPCI). The estimation of GHG emissions showed that 280,558 tonnes of CO2e/year was generated from the port and port-related facilities. Several GHG mitigation strategies and their impact are quantified and discussed. The technology suggestions presented in the paper will be very useful to plan effective mitigation strategies incorporating technological advancement and management policies

Investigation on the High Vacuum Tribological Characteristics of Surface Treated Nuclear Grade Stainless Steel Type AISI 316 LN at 25 to 500 degrees C

Although some researchers have published friction and wear data of Plasma Nitride (PN) coatings, the tribological behavior of PN/PN Pairs in high vacuum environment has not been published so far In order to bridge this knowledge gap, tribological tests under dry conditions have been conducted on PN/PN Pairs for varying temperatures of 25, 200, 400 and 500 degrees C in high vacuum (1.6 x 10(-4) bar) environment. The PN coatings showed good wear resistance layer on the ring surface. The PN coatings were removed only from the pin surface for all the tests since it contacts at a point. The friction and wear were low at lower temperatures and it eliminated adhesion between the contact surfaces until the coating was completely removed from the pin surface. (C) 2011 Journal of Mechanical Engineering. All rights reserved