Satish C. Sharma

Bio: Satish C. Sharma is an academic researcher from Indian Institute of Technology Roorkee. The author has contributed to research in topics: Bearing (mechanical) & Reynolds equation. The author has an hindex of 30, co-authored 233 publications receiving 3639 citations. Previous affiliations of Satish C. Sharma include Indian Institutes of Technology.

Performance evaluation of a copper omega type Coriolis mass flow sensor with an aid of ANFIS tool

Abstract: The performance evaluation of a copper omega type Coriolis mass flow sensor using an adaptive neuro-fuzzy inference system (ANFIS) has been studied for influencing input design parameters. The exhaustive experimentation has been carried out under various operational conditions and further this data set is utilized for modeling using ANFIS. The results are in good agreement with the experimental results stating that this technique may be applied to predict the performance of mass flow sensor.

Dynamic characteristics of compensated hydrostatic thrust pad bearing subjected to external transverse magnetic field

Abstract: This article presents finite element analysis to evaluate the performance of a compensated hydrostatic circular thrust pad bearing in the presence of a magnetic field. The influence of the magnetic field on the flow of an electrically conducting lubricant is expressed by incorporating the Lorentz force in the momentum equation, described by Maxwell equations and Ohm’s law. The modified Reynolds equation has been derived for a lubricant blended with long-chain polymer additives flowing in the presence of a transverse magnetic field. The Stokes couple stress theory has been used to describe effect of such additives on lubricant rheology. A source code has been developed in MATLAB to solve the modified Reynolds equation coupled with restrictor flow equations using the finite element method. The performance characteristics of the bearing system are evaluated in terms of pocket pressure, load-carrying capacity, lubricant flow rate, fluid film stiffness and damping coefficient. Comparative studies have been carried out for orifice and capillary compensated bearings. The limiting cases of the modified Reynolds equation yield performance characteristics of specific lubricants such as electrically conducting couple stress lubricant, couple stress lubricant, electrically conducting lubricant and Newtonian lubricant. It is noticed that the load-carrying capacity, fluid film stiffness and damping capabilities of the bearing get enhanced quite substantially in the presence of couple stress additives and a magnetic field.

Evaluation of the Mechanical Properties of CNT Based Composites Using Hexagonal RVE

Abstract: Carbon nanotubes (CNTs) possess extremely high stiffness, strength, and resilience, and may provide ultimate reinforcing materials for the development of nanocomposites In this paper, the effective material properties of CNT-based composites are evaluated based on the continuum mechanics using a hexagonal representative volume element (RVE) Numerical equations are used to extract the effective material properties from numerical solutions for the hexagonal RVEs under axial loading case An extended rule of mixtures for estimating effective Young’s modulus in the axial direction of the RVE is applied It has been observed that the addition of the CNTs in a matrix at volume fractions of only about 36%, the stiffness of the composite is increased by 33% for long CNT at Et/Em=10, whereas not much improvement in stiffness has been noticed in the case of short CNTS at Et/Em=10 Effectiveness of composites is evaluated in terms of various dimensions such as thickness, diameter, and length of CNT These results suggest that short CNTs in a matrix may not be as effective as long CNTs in reinforcing a composite The simulation results are consistent with the experimental ones reported in literature Also, the comparative evaluation of all three types of RVEs is presented here

Study of two‐lobe four recessed hybrid journal bearing

Abstract: Purpose – In recent years, researchers have focused a great deal of attention on multirecess hybrid journal bearing systems. The non‐circular journal bearings are widely used in industry on account of their better stability, simplicity, efficiency and low cost. The purpose of this paper is to present a theoretical investigation into the performance of a two‐lobe multirecess hybrid journal bearing system.Design/methodology/approach – The Reynold's equation governing the lubricant flow in the clearance space between the journal and bearing together with restrictor flow equations has been solved using finite element method. The bearing static and dynamic performance characteristics have been presented for the various values of the offset factors (0.75, 1, 1.25 and 1.50) for the hybrid mode of operation of the journal bearing system compensated by capillary and orifice restrictors for the commonly used bearing operating and geometric parameters. The offset of the journal has been accounted for by defining a n...

Effect of geometric shape of micro-grooves on the performance of textured hybrid thrust pad bearing

Abstract: A numerical simulation is performed to investigate the synergizing influence of surface texture (micro-grooves) and electrically conducting lubricant on static and dynamic performance of hybrid thrust pad bearings operating under transverse magnetic field. Linear momentum and mass conservation equation are solved simultaneously to derive modified Reynolds equation for magnetohydrodynamic lubrication. Finite element approach has been used to obtain couple solution of modified Reynolds equation and restrictor (orifice) flow equation. A mass conserving algorithm (Jakobsson–Floberg–Olsson boundary condition) has been implemented to simulate cavitation phenomenon within micro-grooves. A parametric investigation (based on load-carrying capacity/fluid film pressure) is carried out to obtain optimum attributes for various micro-grooves shapes. Providing micro-groove on bearings surfaces results in a significant increase in load-carrying capacity, stiffness coefficient and reduction in frictional power loss of the bearing. Employing of electrically conducting lubricant is seen to be enhancing the load-carrying capacity and damping characteristics of the bearing.

Electrochemical Sensors and Biosensors

Abstract: This review covers advances in electrochemical and biochemical sensor development and usage during 2010 and 2011 In choosing scholarly articles to contribute to this review, special emphasis was placed on work published in the areas of reference electrodes, potentiometric sensors, voltammetric sensors, amperometric sensors, biosensors, immunosensors, and mass sensors In the past two years there have been a number of important papers, that do not fall into the general subsections contained within the larger sections Such novel advances are very important for the field of electrochemical sensors as they open up new avenues and methods for future research Each section above contains a subsection titled “Other Papers of Interest” that includes such articles and describes their importance to the field in general For example, while most electrochemical techniques for sensing analytes of interest are based on the changes in potential or current, Shan et al1 have developed a completely novel method for performing electrochemical measurements In their work, they report a method for imaging local electrochemical current using the optical signal of the electrode surface generated from a surface plasmon resonance (SPR) The electrochemical current image is based on the fact that the current density can be easily calculated from the local SPR signal The authors demonstrated this concept by imaging traces of TNT on a fingerprint on a gold substrate Full articles and reviews were primarily amassed by searching the SciFinder Scholar and ISI Web of Knowledge Additional articles were found through alternate databases or by perusing analytical journals for pertinent publications Due to the reference limitation, only publications written in English were considered for inclusion Obviously, there have been more published accounts of groundbreaking work with electrochemical and biochemical sensors than those covered here This review is a small sampling of the available literature and not intended to cover every advance of the past two years The literature chosen focuses on new trends in materials, techniques, and clinically relevant applications of novel sensors To ensure proper coverage of these trends, theoretical publications and applications of previously reported sensor development were excluded We want to remind our readers that this review is not intended to provide comprehensive coverage of electrochemical sensor development, but rather to provide a glimpse of the available depth of knowledge published in the past two years This review is meant to focus on novel methods and materials, with a particular focus on the increasing use of graphene sheets for sensor material development For readers seeking more information on the general principles behind electrochemical sensors and electrochemical methods, we recommend other sources with a broader scope2, 3 Electrochemical sensor research is continually providing new insights into a variety of fields and providing a breadth of relevant literature that is worthy of inclusion in this review Unfortunately, it is impossible to cover each publication and unintentional oversights are inevitable We sincerely apologize to the authors of electrochemical and biochemical sensor publications that were inadvertently overlooked