Current Affairs Railways

Automobile Engineering   Automobile engineering, incorporating elements of Mechanical, electrical, electronic, software and safety Engineering as applied to the design, manufacture and operation of motorcycles, automobiles, buses and trucks and their respective engineering subsystems.
  • Some of the engineering attributes and disciplines that are of importance to the automotive engineer and many of the other aspects are included in it:
  • Safety engineering: Safety engineering is the assessment of various crash scenarios and their impact on the vehicle occupants.
  • Fuel economy/emissions: Fuel economy is the measured fuel efficiency of the vehicle in miles per gallon or kilometers per litre.
  • Vehicle dynamics: Vehicle dynamics is the vehicle’s response of the following attributes: ride, handling, steering, braking, comfort and traction.
  • NVH engineering: NVH is the customer's feedback (both tactile [felt] and audible [heard]) from the vehicle. While sound can be interpreted as a rattle, squeal, or hoot; a tactile response can be seat vibration, or a buzz in the steering wheel.
  • Vehicle Electronics: Automotive electronics is an increasingly important aspect of automotive engineering. Modern vehicles employ dozens of electronic systems.
  • Performance: Performance is a measurable and testable value of a vehicles ability to perform in various conditions. Performance can be considered in a wide variety of tasks, but it's generally associated with how quickly a car can accelerate.
  •        Shift quality: Shift quality is the driver's perception of the vehicle to an automatic transmission shift event. This is influenced by the powertrain (engine, transmission), and the vehicle (driveline, suspension, engine and powertrain mounts, etc.) Shift feel is both a tactile (felt) and audible (heard) response of the vehicle. Durability/corrosion engineering: Durability and corrosion engineering is the evaluation testing of a vehicle for its useful life. Tests include mileage accumulation, severe driving conditions, and corrosive salt baths.
  •        Package / ergonomics engineering: Package engineering is a discipline that designs/analyzes the occupant accommodations (seat roominess), ingress/egress to the vehicle, and the driver's field of vision (gauges and windows). The package engineer is also responsible for other areas of the vehicle like the engine compartment, and the component to component placement.
  • Ergonomics is the discipline that assesses the occupant's access to the steering wheel, pedals, and other driver/ passenger controls.
  • Climate control: Climate control is the customer's impression of the cabin environment and level of comfort related to the temperature and humidity. From the windshield defrosting, to the heating and cooling capacity, all vehicle seating positions are evaluated to a certain level of comfort.
  • Drivability: Drivability is the vehicle's response to general driving conditions. Cold starts and stalls, RPM dips, idle response, launch hesitations and stumbles, and performance levels.
  • Cost: The cost of a vehicle program is typically split into the effect on the variable cost of the vehicle, and the up-front tooling and fixed costs associated with developing the vehicle. There are also costs associated with warranty reductions, and marketing.
  • Program timing: To some extent programs are timed with respect to the market, and also to the production schedules more...

Instrument Mechanical  
  • Instrumentation engineering is the engineering specialization focused on the principle and operation of measuring instruments that are used in design and configuration of automated systems in electrical, pneumatic domains etc.
  • They typically work for industries with automated
Processes, such as chemical or manufacturing plants, with the goal of improving system productivity, reliability, safety, optimization, and stability.
  • To control the parameters in a process or in a particular system, devices such as microprocessors, microcontrollers or PLCs are used, but their ultimate aim is to control the parameters of a system.
  • Instrumentation engineering is loosely defined because the required tasks are very domain dependent. An expert the biomedical instrumentation of laboratory rats has very different concerns than the expert in rocket instrumentation. Common concerns of both are the selection of appropriate sensors based on size, weight, cost, reliability, accuracy, longevity, environmental robustness and frequency response. Some sensors are literally fired in artillery shells. Others sense thermonuclear explosions until destroyed. Invariably sensor data must be recorded, transmitted or displayed. Recording rates and capacities vary enormously.
Transmission can be trivial or can be clandestine, encrypted and low-power in the presence of jamming. Displays can be trivially simple or can require consultation with human factors experts. Control system design varies from trivial to a separate specialty.
  • Instrumentation engineers are commonly responsible for integrating the sensors with the recorders, transmitters, displays or control systems. They may design or specify installation, wiring and signal conditioning. They may be responsible for calibration, testing and maintenance of the system.
  • In a research environment it is common for subject matter experts to have substantial instrumentation system expertise. An astronomer knows the structure of the universe and a great deal about telescopes - optics, pointing and cameras (or other sensing elements). That often includes the hard-won knowledge of the operational procedures that provide the best results. For example, an astronomer is often knowledgeable of techniques to minimize temperature gradients that cause air Turbulence within the telescope.
  • Instrumentation is the use of measuring instruments to monitor and control a process.
  • It is the art and science of measurement and control of process variables within a production, laboratory, or manufacturing area.
  • An instrument is a device that measures a physical quantity such as flow, temperature, level, distance, angle, or pressure. Instruments may be as simple as direct reading thermometers or may be complex multi variable process analyzers.
  • Instruments are often part of a control system in refineries, factories, and vehicles. The control of processes is one of the main branches of applied instrumentation. Instrumentation can also refer to handheld devices that measure some desired variable.
  • Diverse handheld instrumentation is common in laboratories, but can be found in the household as well. For example, a smoke detector is a common instrument found in most western homes.
  • Instruments attached to a control system may provide signals used to operate solenoids, valves regulators, circuit breakers, or relays. These devices control a desired output variable, more...

Thermodynamics  
  • Thermodynamics is a branch of physics concerned with heat and temperature and their relation to energy and work. It defines macroscopic variables, such as internal energy, entropy, and pressure that partly describe a body of matter or radiation.
  • It states that the behavior of those variables is subject to general constraints that are common to all materials, not the peculiar properties of particular materials. These general constraints are expressed in the four laws of thermodynamics.
  • Thermodynamics describes the bulk behavior of the body, not the microscopic behaviors of the very large numbers of its microscopic constituents, such as molecules.
  • Its laws are explained by statistical mechanics, in terms of the microscopic constituents.
  • Thermodynamics applies to a wide variety of topics in science and engineering.
  • Thermo-dynamics is the subject of the relation of heat to forces acting between contiguous parts of bodies, and the relation of heat to electrical agency.
  • Initially, thermodynamics, as applied to heat engines, was concerned with the thermal properties of their 'working materials' such as steam, in an effort to increase the efficiency and power output of engines.
  • The plain term 'thermo-dynamics' refers to a macroscopic description of bodies and processes.
  • Thermodynamics arose from the study of two distinct kinds of transfer of energy, as heat and as work, and the relation of those to the system's macroscopic variables of volume, pressure and temperature. Transfers of matter are also studied in thermodynamics.
  • Thermodynamic equilibrium is one of the most important concepts for thermodynamics. The temperature of a thermodynamic system is well defined, and is perhaps the most characteristic quantity of thermodynamics.
  • In engineering practice, thermodynamic calculations deal effectively with such systems provided the equilibrium thermodynamic variables are nearly enough well-defined.
  • Central to thermodynamic analysis are the definitions of the system, which is of interest, and of its surroundings. The surroundings of a thermodynamic system consist of physical devices and of other thermodynamic systems that can interact with it.
  • An example of a thermodynamic surrounding is a heat bath, which is held at a prescribed temperature, regard- less of how much heat might be drawn from it.
  • There are four fundamental kinds of physical entities in thermodynamics, states of a system, walls of a system, thermodynamic processes of a system, and thermodynamic operations.
  • A thermodynamic system can be defined in terms of its states. In this way, a thermodynamic system is a macroscopic physical object, explicitly specified in terms of macroscopic physical and chemical variables that describe its macroscopic properties.
  • A thermodynamic operation is an artificial physical manipulation that changes the definition of a system or its surroundings. Usually it is a change of the permeability or some other feature of a wall of the system that allows energy (as heat or work) or matter (mass) to be exchanged with the environment.
  • A thermodynamic system can also be defined in terms of the cyclic processes that it can undergo.       
  • A cyclic process is a cyclic sequence of thermo-dynamic operations and more...

Fluid Mechanics  
  • Fluid mechanics is the branch of physics which involves the study of fluids and the forces on them. Fluid mechanics can be divided into fluid statics, the study of fluids at rest; and fluid dynamics, the study of the effect of forces on fluid motion.
  • It is branch of continuum mechanics, a subject which models matter without using the information that it is made out of atoms; that is, it models matter from a macroscopic viewpoint rather than from microscopic.
  • Fluid mechanics, especially fluid dynamics, is an active field research with many problems that are partly or wholly unsolved.
  • Fluid mechanics can be mathematically complex, and can be solved by numerical methods, typically using computers. A modem discipline, called computational fluid dynamics (CFD), is devoted to this approach to solving fluid mechanics problems.
  • Particle image velocimetry, an experimental method for visualizing and analyzing fluid flow, also takes advantage of the highly visual nature of fluid flow.
  • The study of fluid mechanics goes back at least to the days of an ancient Greece, when Archimedes investigated fluid statics and buoyancy and formulated his famous law known now as the Archimedes' principle, which was published in his work On Floating Bodies - generally considered to be the first major work on fluid mechanics.
  • Fluid statics or hydrostatics is the branch of fluid mechanics that studies fluids at rest. It embraces the study the conditions under which fluids are at rest in stable equilibrium; and is contrasted with fluid dynamics, the study of fluids in motion.
  • Hydrostatics is fundamental to hydraulics, the engineering of equipment for storing, transporting and using fluids. It is also relevant to geophysics and astrophysics to meteorology, to medicine and many other fields.
  • Hydrostatics offers physical explanations for many phenomena of everyday life, such as why atmospheric pressure changes with altitude, why wood and oil float on water, and why the surface of water is always flat and horizontal whatever the shape of its container.
  • Fluid dynamics is a sub discipline of fluid mechanics that deal with fluid flow-the natural science of fluids in motion.
  • It has several sub disciplines itself, including aerodynamics and hydrodynamics. Fluid dynamics has a wide range of applications, including calculating force and moments on aircraft, determining the mass flow rate of petroleum through pipelines, predicting weather patterns, understanding nebulae in interstellar space and modelling fission weapon detonation.
  • Some of its principles are even used in traffic engineering, where traffic is treated as a continuous fluid, and crowd dynamics.
  • Fluid dynamics offers a systematic structure-which underlies these practical disciplines-that embraces empirical and semi-empirical laws derived from flow measurement and used to solve practical problems.
  • The solution to a fluid dynamics problem typically involves calculating various properties of the fluid, such as velocity, pressure, density, and temperature, as functions of space and time.
  • Like any mathematical model of the real world, fluid mechanics makes some basic assumptions about the materials being studied. These assumptions are turned into equations more...

Turbomachinery           
  • Turbo machinery, in mechanical engineering, describes machines that transfer energy between a rotor and a fluid, including both turbines and compressors.
  • While a turbine transfers energy from a fluid to a rotor, a compressor transfers energy from a rotor to a fluid. The two types of machines are governed by the same basic relationships including Newton's second Law of Motion and equation for compressible fluids.
  • Centrifugal pumps are also turbo machines that transfer energy from a rotor to a fluid, usually a liquid, while turbines and compressors usually work with a gas.
  • In general, the two kinds of turbo machines encountered in practice are open and closed turbo machines.
  • Open machines such as propellers, windmills, and enshrouded fans act on an infinite extent of fluid, whereas, closed machines operate on a finite quantity of fluid as it passes through a housing or casing.
  • Turbo machines are also categorized according to the type of flow. When the flow is parallel to the axis of rotation, they are called axial flow machines, and when flow is perpendicular to the axis of rotation, they are referred to as radial (or centrifugal) flow machines.    
  • There is also a third category, called mixed flow machines, where both radial and axial flow velocity components are present.
  • Turbo machines may be further classified into two additional categories: those that absorb energy to increase the fluid pressure, i.e. pumps, fans, and compressors, and those that produce energy such as turbines by expanding flow to lower pressures.
  • Certainly there are significant differences between these machines and between the types of analysis that are typically applied to specific cases. This does not negate the fact that they are unified by the same underlying physics of fluid dynamics, gas dynamics, aerodynamics, hydrodynamics, and thermodynamics.
 
\[-\] Radial turbine \[-\] axial compressor
\[-\] Axial fan \[-\] Centrifugal compressor
\[-\] more...
Power Plant Engineering  
  • Power engineering is a subfield of energy engineering that deals with the generation, transmission, distribution and utilization of electric power and the electrical devices connected to such systems including generators, motors and transformers.
  • Although much of the field is concerned with the problems of three-phase AC power - the standard for large scale power transmission and distribution across the modem world \[-\,a\] significant fraction of the field is concerned with the conversion between AC and DC power and the development of specialized power systems such as those used in aircraft or for electric railway networks.
  • It was a subfield of electrical engineering before the emergence of energy engineering.
  • Electricity became a subject of scientific interest in the late 17th century with the work of William Gilbert.
  • Over the next two centuries a number of important
  • Discoveries were made including the incandescent light bulb and the voltaic pile. Probably the greatest discover with respect to power engineering came from Michael faraday who in 1831 discovered that a change in magnetic flux induces an electromotive force in a loop of wire-a principle known as electromagnetic induction that helps explain how generators and transformers work.
  • In 1881 two electricians built the world's first power station at Godalming in England.
  • The Edison Electric Light Company, developed the first steam powered electric power station on Pearl Street in New York City.
  • In 1885 the Italian physicist and electrical engineer Galileo Ferraris demonstrated an induction motor and in 1887 and 1888 the Serbian-American engineer Nikola Tesla filed a range of patents related to power systems including one for a practical two-phase induction motor which Westinghouse licensed for his AC system
  • By 1890 the power industry had flourished and power companies had built literally thousands of power systems (both direct and alternating current) in the United States and Europe \[-\] these networks were effectively dedicated to providing electric lighting.
  • In 1891, Westinghouse installed the first major power system that was designed to drive an electric motor and not just provide electric lighting. The installation powered a 100 horsepower (75 kW) synchronous motor at Telluride, Colorado with the motor being started by a Tesla induction motor.
  • Although the 1880s and 1890s were seminal decades in the field, developments in power engineering continued throughout the 20th and 21st century. In 1936 the first commercial high-voltage direct current (HVDC) line using mercury-arc valves was built between Schenectady and Mechanicville, New York.
  • In 1957 Siemens demonstrated the first solid-state rectifier however it was not until the early 1970s that this technology was used in commercial power systems.
  • In 1959 Westinghouse demonstrated the first circuit breaker that used SF6 as the interrupting medium. SF6 is a far superior dielectric to air and, in recent times, its use has been extended to produce far more compact switching equipment and transformers.
  • Many important developments also came from extending innovations in the ICT field to the power engineering field. For example, the development of computers meant more...

Engineering Mechanics  
  • Engineering mechanics is the application of mechanics to solve problems involving common engineering elements.
  • The goal of this Engineering Mechanics course is to expose students to problems in mechanics as applied to plausibly real-world scenarios.
  • Dynamics all which are all highly applicable in engineering. But the most important part of them is statics (study of body at rest) which is not only a base for all others, but also have the highest engineering application.
  • Physics also involve optics, waves, quantum, and relativity theory, which have no fundamental engineering application yet.
  • Forces act along the members, and there are no shear forces or moments. A truss is therefore defined as a system composed entirely of two-force members, which only carry axial loads.
  • The ends of a truss are pinned, so that they don't carry moments. The only reactions at the ends of a truss member are forces. External forces on trusses act only on the end points.
  • Truss problems are solved by the method of sections, where an imaginary cut is made through the member(s) of interest, and global equilibrium of forces and moments are used to determine the forces in the members, or by the method of joints, in which a single join is isolated and analyzed and the resulting forces (not necessarily with a numerical value) are transferred to adjacent joints, where the process is repeated.
  • Applied mechanics is a branch of the physical sciences and the practical application of mechanics.
  • Applied mechanics examines the response of bodies (solids and fluids) or systems of bodies to external forces. Some examples of mechanical systems include the flow of a liquid under pressure, the fracture of a solid from an applied force, or the vibration of an ear in response to sound.
  • A practitioner of the discipline is known as a mechanician.
  • Applied mechanics, as its name suggests, bridges the gap between physical theory and its application to technology.
  • As such applied mechanics is used in many fields of engineering, especially mechanical engineering. In this context, it is commonly referred to as engineering mechanics.
  • Much of modem engineering mechanics is based on Isaac Newton's laws of motion while the modern practice of their application can be traced back to Stephen Timoshenko, who is said to be the father of modern engineering mechanics.
  • Within the theoretical sciences, applied mechanics is useful in formulating new ideas and theories, discovering and interpreting phenomena, and developing experimental and computational tools.
  • In the application of the natural sciences, mechanics was said to be complemented by .Lewis and Merle Randall, the study of heat and more generally energy, and electro mechanics, the study of electricity and magnetism.
  • The current carrying wire wound spirally in the form of helix is known as solenoid or coil.
  • When a current carrying conductor is placed at right angle to the direction of magnetic field, a mechanical force is experienced on the conductor in a direction perpendicular to both the direction of magnetic field more...

Strength of Materials  
  • Strength of materials, is a subject which deals with the behavior of solid objects subject to stresses and strains.
  • The complete theory began with the consideration of the behavior of one and two dimensional members of structures, whose states of stress can be approximated as two dimensional, and was then generalized to three dimensions to develop a more complete theory of the elastic and plastic behavior of materials.
  • An important founding pioneer in mechanics of materials was Stephen Timoshenko.
  • The study of strength of materials often refers to various methods of calculating the stresses and strains in structural members, such as beams, columns, and shafts.
  • The methods employed to predict the response of a structure under loading and its susceptibility to various failure modes takes into account the properties of the materials such as its yield strength, ultimate strength, Young's modulus, and Poisson's ratio; in addition the mechanical element's macroscopic properties (geometric properties), such as it length, width, thickness, boundary constraints and abrupt changes in geometry such as holes are considered.
  • In materials science, the strength of a material is its ability to withstand an applied load without failure. The field of strength of materials deals with forces and deformations that result from their acting on a material.
  • A load applied to a mechanical member will induce internal forces within the member called stresses when those forces are expressed on a unit basis. The stresses acting on the material cause deformation of the material in various manner.
  • Deformation of the material is called strain when those deformations too are placed on a unit basis. The applied loads may be axial (tensile or compressive), or shear. The stresses and strains that develop within a mechanical member must be calculated in order to assess the load capacity of that member.
  • This requires a complete description of the geometry of the member, its constraints, the loads applied to the member and the properties of the material of which the member is composed. With a complete description of the loading and the geometry of the member, the state of stress and of state of strain at any point within the member can be calculated.
  • Once the state of stress and strain within the member is known, the strength (load carrying capacity) of member, its deformations (stiffness qualities), and stability (ability to maintain its original configuration can be calculated.
  • The calculated stresses may then be compared to some measure of the strength of the member such as its material yield or ultimate strength. The calculated deflection of the member may be compared to a deflection criteria that is based on the member's use.
  • The calculated buckling load of the member may be compared to the applied load. The calculated stiffness and mass distribution of the member may be used to calculate the member's dynamic response and then compared to the acoustic environment in which it will be used.                                
  • Material strength refers to the point on more...

Theory of Machines  
  • The subject Theory of Machines may be defined as that branch of Engineering - Science, which deals with the study of relative motion between the various parts of machine, and forces which act on them. The knowledge of this subject is very essential for an engineer in designing the various parts of a machine.
  • Kinematics -It is that branch of Theory of Machines which deals with the relative motion between the various parts of the machines with out forces applying to it.
  • Dynamics- It is that branch of Theory of Machines which deals with the forces and their effects, while acting upon the machine parts in motion.
  • Kinetics- It is that branch of Theory of Machines which deals with the inertia forces which arise from the combined effect of the mass and motion of the machine parts.
  • Statics- It is that branch of Theory of Machines which deals with the forces and their effects while the machine parts are at rest. The mass of the parts is assumed to be negligible.
  • Kinematics is the branch of mechanics concerned with the motions of objects without being concerned with the forces that cause the motion. In this latter respect it differs from dynamics, which is concerned with the forces that affect motion.
  • There are three basic concepts in kinematics - speed, velocity and acceleration.
  • Whether it's finishing a 5K race or a marathon, completing a sprint triathlon or an Ironman, doing a century ride or a stage race, simply getting back into shape or competing at the highest level in any sport, our goal is to deliver healthy athletes to the starting line, physically and mentally prepared to meet the challenge.
  • Your Kinetic Motion experience begins with a complete evaluation to catch bio-mechanical imbalances before they become injuries. For triathletes, the next step is a video-taped session in the pool with our swim coach.
  • Then we do thorough testing to establish the plateau from which we launch your comprehensive coaching plan. Finally, we provide full-service travel planning to get you to the finest national and international racing venues. We want to take you from the beginning of your journey to the finish line of your dreams.
  • In mechanics and physics, simple harmonic motion is a type of periodic motion where the restoring force is directly proportional to the displacement. It can serve as a mathematical model of a variety of motions, such as the oscillation of a spring.
  • In addition, other phenomena can be approximated by simple harmonic motion, including the motion of a simple pendulum as well as molecular vibration.
  • Simple harmonic motion is typified by the motion of a mass on a spring when it is subject to the linear elastic restoring force given by Hooke's Law. The motion is sinusoidal in time and demonstrates a single resonant frequency.
  • In order for simple harmonic motion to take place, the net force of the object at the end of the pendulum must more...

Vibration Analysis  
  • Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. The oscillations may be periodic such as the motion of a pendulum or random such as the movement of a tire on a gravel road.
  • Vibration is occasionally "desirable". For example, the motion of a tuning fork, the reed in a woodwind instrument or harmonica, or mobile phones or the cone of a loudspeaker is desirable vibration, necessary for the correct functioning of the various devices.
  • More often, vibration is undesirable, wasting energy and creating unwanted sound - noise. For example, the vibrational motions of engines, electric motors, or any mechanical device in operation are typically unwanted.
  • Such vibrations can be caused by imbalances in the rotating parts, uneven friction, the meshing of gear teeth, etc. Careful designs usually minimize unwanted vibrations.
  • The study of sound and vibration are closely related. Sound, or "pressure waves", are generated by vibrating structures, these pressure waves can also induce the vibration of structures hence, when trying to reduce noise it is often a problem in trying to reduce vibration.
  • Free vibration occurs when a mechanical system is set off with an initial input and then allowed to vibrate freely. Examples of this type of vibration are pulling a child back on a swing and then letting go or hitting a tuning fork and letting it ring.
  • The mechanical system will then vibrate at one or more of its "natural frequency" and damp down to zero.
  • Forced vibration is when a time-varying disturbance is applied to a mechanical system. The disturbance can be a periodic, steady-state input, a transient input, or a random input.
  • The periodic input can be a harmonic or a non-harmonic disturbance. Examples of these types of vibration include a shaking washing machine due to an imbalance, transportation vibration or the vibration of a building during an earthquake.
  • For linear systems, the frequency of the steady-state vibration response resulting from the application of a periodic, harmonic input is equal to the frequency of the applied force or motion, with the response magnitude being dependent on the actual mechanical system.
  • Vibration testing is accomplished by introducing a forcing function into a structure, usually with some type of shaker. Alternately, a DUT (device under test) is attached to the "table" of a shaker. Vibration testing is performed to examine the response of a device under test (DUT) to a defined vibration environment.
  • The measured response may be fatigue life, resonant frequencies or squeak and rattle sound output (NVH). Squeak and rattle testing is performed with a special type of quiet shaker that produces very low sound levels while under operation.
  • For relatively low frequency forcing, servo hydraulic (electrohydraulic) shakers are used. For higher frequencies, electro dynamic shakers are used. Generally, one or more "input" or "control" points located on the DUT-side of a fixture is kept at a specified acceleration.
  • Other "response" points experience maximum vibration level (resonance) or minimum vibration level (anti-resonance). more...


You need to login to perform this action.
You will be redirected in 3 sec spinner