Jump to content
Mechanical Engineering


Popular Content

Showing content with the highest reputation since 12/08/2010 in all areas

  1. 15 points


    Powerpoint Notes on Metal forming Topic includes— Hot &Cold working Forging Extrusion Rolling Drawing
  2. 14 points
    Om Prakash

    Difference between pump and compressor

    Pumps can handle both liquids and gases. But Compressor can handle only the gases due the incompressible nature of liquids.................
  3. 12 points
    Most of the time gears are used for reduction. So pinion is smaller as compared to gear, i.e. no of teeth on pinion are less as compared to gear. This in accordance affects the number of cycles. Thus in any operation, pinion performs more cylces as compared to gear. More cycles means more wear and hence generally pinion material is selected such that its hardness is more than material of Gear.
  4. 12 points

    Difference between Pipes and Tubes?

    Basic Difference is the how their are measured.. [1] i.e. A pipe is measured by ID(inner diameter) and a tube is measured by OD(outer diameter). [2] a pipe is like a vessel to store a liquid/gas so inside volume is important factor, while a tube is seen as structual member so total volume is important factor.
  5. 11 points

    Catia 3D Design

    Version 1.1


  6. 11 points
    I have been encouraged to contribute to the Mechanical Engineering web site by Dr. D. I have started the blog "Not Taught in Class". The purpose of the blog is to provide examples of lessons learned in the field that you would not learn in class. These stories are not white papers, just real life examples of things not expected and problems solved. The blog postings will also attempt to provide insight and perspective that comes with many years in the field of engineering. I hope the blog postings will be informative and in many cases entertaining.
  7. 10 points
    Machine is a device to transmit force it may or may not produce power whereas Engine is used to produce power.
  8. 10 points
    Aakarshan Satheesh Kumar

    Explain why washers are used?

    Washers are used when bolting to make stronger the joint and to reduce bolt fatigue due to inconsistent loads. Any stretch or flattening of parts is likely to be less than the compression of the washer thus, the bolt won't loosen much.
  9. 9 points
    1.)Micro hole drilling machine 2.)Motorized jack 3.)Multipurpose Tool Changer 4.)Over Load Indicator for machines 5.)Pneumatic hag saw cutter 6.)Pneumatic Punch 7.)Automatic pollution control system 8.)Motorized wheel chair Share your project ideas
  10. 9 points
    1. pressure represent intensity of external forces acting at a point. but stress represent intensity of internal resisting forces develop at a point.2. pressure is always acts normal to the surface. but but stress may also act either normal or parallel to the surface.3. magnitude of pressure at a point in all direction remain same. but magnitude of stress at a point in all the direction are unequal.4. pressure can be measure by using measuring device.like pressure gauge. but stress can't be measure directly by using any device.
  11. 9 points
    Sirazz92 has given a fairly good answer. Pressure usually refers to a distributed external load applied to a body. Stress is the distributed internal loading associated with displacement under load. DrD
  12. 8 points
    What type of joint is used to connect two rods subjected to a) tensile loads only and tensile or compressive loads? 1. You can answer this question 2. You can like the best answer 3. You can share the question.
  13. 7 points
    What is the Difference between 'Thermodynamics and Heat Transfer'? (Question given by Ayesha) 1. You can answer this question 2. You can like the best answer 3. You can share the question..
  14. 7 points
    hi....till now we have a bicycle in which we have to change the gear by the help of our hand.....but i want to make a bicycle in which gears change automatically with change in speed.. like.. 1-5km/hr in 1st gear 5-10km/hr in 2nd gear 10-14km/hr in 3rd gear 14-25km/hr in 4th gear... it is a mini project...if u have any suggestions then please give me... hope that all of u will definately give ur valueable suggestions..... waiting for ur reply.....
  15. 7 points
    Because a properly designed duct, will deliver and remove air giving a good quality of air indoors and also thermal comfort. Thus they are necessary for ventilation purposes.
  16. 6 points
    Hardness: Hardness is the resistance of a material to localized deformation. The term can apply to deformation from indentation, scratching, cutting or bending. hardness commonly refers to a material's ability to penetrate softer materials. An object made of a hard material will scratch an object made of a softer material.In metals, ceramics and most polymers, the deformation considered is plastic deformation of the surface. For elastomers and some polymers, hardness is defined at the resistance to elastic deformation of the surface. The lack of a fundamental definition indicates that hardness is not be a basic property of a material, but rather a composite one with contributions from the yield strength, work hardening, true tensile strength, modulus, and others factors. Hardness measurements are widely used for the quality control of materials because they are quick and considered to be nondestructive tests when the marks or indentations produced by the test are in low stress areas. Toughness: The quality known as toughness describes the way a material reacts under sudden impacts. toughness is the resistance to fracture of a material when stressed. It is defined as the amount of energy that a material can absorb before rupturing, and can be found by finding the area (i.e., by taking the integral) underneath the stress-strain curve. It can be defined as the work required to deform one cubic inch of metal until it fractures. Toughness, often expressed as the Modulus of Toughness, is measured in units of joules per cubic meter (J/m3) in the SI system and pound-force per square inch (sometimes expressed as in-lb/in3) in US customary units. Toughness is measured by the Charpy test or the Izod test. Both of these tests use a notched sample. The location and shape of the notch are standard. The points of support of the sample, as well as the impact of the hammer, must bear a constant relationship to the location of the notch. Difference: The hardness of a metal limits the ease with which it can be machined, since toughness decreases as hardness increases Toughness is a combination of high strength and medium ductility. It is the ability of a material or metal to resist fracture, plus the ability to resist failure after the damage has begun. A tough metal, such as cold chisel, is one that can withstand considerable stress, slowly or suddenly applied, and which will deform before failure. Toughness is the ability of a material to resist the start of permanent distortion plus the ability to resist shock or absorb energy
  17. 6 points
    What is Hydraulic intensifer ? Explain its principle working & applications.
  18. 6 points
    Petrol get ignited with at low temp. But for diesel high temp is required for combustion. ..This sole purpose is not achieved by spark plugs so we go with compression ignition. ...thus we don't have spark plugs in diesel engine. ..
  19. 6 points

    gear manufacturing methods

    We can not use Dies For casting C.I. Components, dear because of shrinking property of C.I. . On cooling, C.I shrinks and traps the core part of the die. It means it is not possible to remove our casted part from the die as it sieze in it. It is mostly happen in dies where there are cores fitted in the dies. Even after giving the draft the casted part could not be removed. This is my own experience, we made a die once for casting Cast Iron. But faced the same problem due to shrinkage of C.I.. Not Succeeded, only Sand casting is the best option for Casting C.I.. So shrinkage is the main reason.
  20. 5 points
    The purpose for a governor on at CI engine is the same as the purpose for a governor on any machine: to maintain constant speed under varying load conditions. DrD
  21. 5 points

    Brake system

  22. 5 points
    Differences between Welding, Soldering and BrazingWelding, Soldering and Brazing are the metal joining process. Each type of joining process has its own significance. Type of joining process to be used for joining two parts depends on many factors. In this article I have covered the differences between the joining processes welding, soldering and brazing. S.NoWelding Soldering Brazing 1Welding joints are strongest joints used to bear the load. Strength of the welded portion of joint is usually more than the strength of base metal.Soldering joints are weakest joints out of three. Not meant to bear the load. Use to make electrical contacts generally.Brazing are weaker than welding joints but stronger than soldering joints. This can be used to bear the load up to some extent.2Temperature required is 3800 degree Centigrade in Welding joints.Temperature requirement is up to 450 degree Centigrade in Soldering joints.Temperature may go to 600 degree Centigrade in Brazing joints.3Work piece to be joined need to be heated till their melting point.Heating of the work pieces is not requiredWork pieces are heated but below their melting point.4Mechanical properties of base metal may change at the joint due to heating and cooling.No change in mechanical properties after joining.May change in mechanical properties of joint but it is almost negligible.5Heat cost is involved and high skill level is required.Cost involved and skill requirements are very low.Cost involved and sill required are in between others two.6Heat treatment is generally required to eliminate undesirable effects of welding.No heat treatment is required.No heat treatment is required after brazing.7No preheating of workpiece is required before welding as it is carried out at high temperature.Preheating of workpieces before soldering is good for making good quality joint.Preheating is desirable to make strong joint as brazing is carried out at relatively low temperature. Differences between Welding Soldering and Brazing.pdf
  23. 5 points
    My answer to that question would have been yes, and like all absolute answers, it would prove to be incorrect. An axiom in manufacturing is that the design engineer should not dictate manufacturing processes unless it is vital to the function of the design, metal vs. plastic, casting vs. forging etc. Once passed the gross requirements, dictating which machine tool to use would be beyond the design engineer’s prerogative unless there was a compelling reason! However, this should not be taken as the design engineer not learning all he can about manufacturing. Requirements come in three major categories. Those we know need special attention, those we expect to happen as a matter of course, and those we did not know existed. If we need a very tight tolerance, we will call it out in the documentation for a specific feature. For the second category, we rely on title block tolerances or good machine shop practice. Those that fall into the third category are discovered when a product has been in production for a while and then a seemingly benign change is made. Often the original design team is no longer in place. Whether the original team thought a requirement in the third category was covered by the in the second category may not be possible to determine. Products go through a test phase to weed out the unknowns before release, but revisions don’t always get the same scrutiny. Here is an example where after hundreds of thousands of units produced a change in manufacturing process caused a failure. The product was a servo assembly that has a 200:1 reduction. It was smaller than a pack of cigarettes and the small DC motor had very little torque at the motor output shaft. I think a person could stop the shaft by hand. Two hundred reductions later there was no way you could prevent rotation at the output of the servo assembly with your bare fingers. Some changes in the manufacturing facility resulted in a turned part being produced on a mill. The part can best be described as an axle with a flange. When the part was turned the figure on the left resulted. The concentric lines represent the fine spiral grooves on the face of the flange produced by the cutting tool when the part was turned. The figure on the right shows the fine swirl marks from an end cutter that circled the axle projecting out of the view towards the reader. The surface finish on the flange face was never specified having it fall into category two. How much friction resulted was never established or never documented because turning produced an assembly that worked. The consultants who designed the servo at the start up of the company were long gone. The new surface condition produced by the end mill increased the friction to the point that the servo would stall. The surface in question was close to the motor so the torque at this interface was not much more than the motor output and a long way off from the 200:1 final reduction. There are a few lessons here:1) minor changes are not always minor, 2) good shop practices are a risky thing to rely on, 3) when something stops working look for the third category of requirements, 4) ask yourself what exists in a part that is not defined or inspected, 5) the design engineer needs to be close to manufacturing even when he needs to remain silent on process selection, 6) manufacturing should notify engineering when changes are made to a process that has been in place for a long time. I wish I could claim credit for discovering the cause and fix but a very sharp manufacturing engineer named Bob C residing at headquarters identified the cause.
  24. 5 points

    Spark Plug

  25. 5 points
    There is probably no better chronicler into the full depth of American ingenuity than YouTube. Here one finds not just computer models for all manner of esoteric combustion engine designs, but actual working prototypes of them, often built by individuals. Big companies can also innovate here sometimes. A new free piston engine linear generator (FPEG) from Toyota Central in Maine is a case in point. The piston is called “free” because there is no crankshaft. On its power stroke, the piston dumps its kinetic energy into the fixed windings which surround it, generating a shot of three-phase AC electricity. It can be run sparkless through a diesel cycle or run on standard gasoline. What has folks excited is the claimed thermal efficiency for the device — at 42% it blows away the engines used in cars today. Toyota’s demo engine, just 8 inches around and 2 feet long, was able to generate 15 hp. A two-cylinder model would be self-balancing and have much reduced vibration. Not surprisingly, the valves are electrically operated and can therefore be better used to fine-tune the power delivery through the full range of the stroke. Speaking of strokes, the video indicates a two-stroke design, which might present a few problems for a road-worthy design. For one thing, emissions would be suspect. Nonetheless Toyota imagines that a twin unit design pumping out 20 kW could power a light electric vehicle at a cruise speed of 120 kph (75 mph). Toyota's FPEG, in colorLinear generators and linear combustion engines are nothing new. Shake-to-charge “Faraday” flashlights, smartphones, and even energy-harvesting backpacks are all standard fare, while single-acting direct power pistons have also seen action in applications as intriguing as power-assist boots for the Russian military. The trick is to get the two working efficiently in unison and that is the beauty of what Toyota appears has done. Considering that the piston is decelerated and re-accelerated at each end of the stroke, any mismatch between combustive power input and electromagnetic power extraction needs to be absorbed somewhere. Mechanical or air springs can help although there is still likely to be some efficiency loss. At the risk of adding some confusion, the device is technically an alternator as it generates AC. As (most) electric cars use 3-phase AC induction or “AC-like” 3-phase brushless DC motors, they could potentially run directly from the output of this device, perhaps save for some intermediary voltage and current conditioning. However, like standard car alternators, there will likely be DC conversion to charge the battery pack — unless Toyota has also secretly perfected the AC battery. There is still plenty of room to innovate here. Linear alternators are similar in design to linear motors, but one does not simply reverse the cycle to swap one into the other — there are certain control functions that need to be imposed on how the coils are energized in a motor. However that does not mean a multipurpose linear electric power device could not be constructed.
  26. 5 points
    When we manufacture any product, usually we manufacture it by casting or forging process. To get a proper surface finish of that product we need a proper machining. At the time of maching a certain amount of material usually removed from the surface of the core product. For this reason a tolerance is needed over the designed dimension to maintain the actual dimension. Beside this reason, tolerances also kept to maintain the needed dimension after thermal expansion or contraction at the time of solidification during casting process.
  27. 5 points
    Petrol get ignited with at low temp. But for diesel high temp is required for combustion. ..This sole purpose is not achieved by spark plugs so we go with compression ignition. ...thus we don't have spark plugs in diesel engine. ..
  28. 5 points
    Lisho Thomas

    What is knurling? For what knurling is used?

    A forming process that adds a pattern on the exterior of a workpiece, either for cosmetic reasons or better handling. Knurling is a manufacturing process, typically conducted on a lathe, whereby a diamond-shaped pattern is cut or rolled into metal.
  29. 5 points
    In normal helical gears there is no problem of impact stresses but there are axial thrusts on the bearings of shafts on which they are mounted.these gears are good for moderate power transmission because bearing can be designed.But in very high power transmission design of bearing for a small and compact system becomes very tough and unemployable.Thus herringbone gears were designed to eliminate these axial thrusts.This gear contains both right hand helical profile and left hand helical profile on same gear as you can see in diag. .The axial components of transmission force is cancelled by each other on same gear.Thus eliminating the problem of thrust force. these gears are used in racing cars where high power transmission is required and bearing size can not be increased after certain limit.
  30. 5 points
    In Bilateral tolerance the limit dimensions are given above and below the nominal size.. In unilateral tolerance the limit dimensions are only above the nominal size OR only below the nominal size.
  31. 4 points

    Challenges before Mechanical Engineers

    Is the author an engineer, or a politician? He talks about achieving wonders, but there is a disconnect with reality in his thinking. He speaks of doing amazing things, but he does not relate them to our current knowledge. As such, they look much more like the false promises of politicians seeking election by promising this, that, and the other. How do you see mechanical engineers working on reverse engineering the brain? How do you see mechanical engineers combating the problems of an aging population? How do you see mechanical engineers solving national security problems? It is true that MEs have a role to play in all of these, but to think that we are going to totally solve these problems by engineering is naive. Technology can play a role, but these are largely societal problems, and society must decide how it will solve them to a large extent. Let me cite an example. In the earliest days of nuclear power, it was promised to be too cheap to meter. They told everyone that electric power would be simply given away, or maybe that you would pay a flat rate for any amount of power you wanted to use. It has not turned out that way. Nuclear power is still fairly expensive to produce, in part because of the safety and environmental constraints placed on the process by society. We cannot have our cake and eat it too! Engineering can only work within the rules laid down by society as to what will be accepted and what will not.
  32. 4 points
    Hello guys, how you doing? I'm currently thinking of working on train which will use the windmill technology. As train runs faster facing no traffic jam and the air pushing inward while the train will start to run, so I think it pave the way to reduce energy crisis. What do you think? Anyone interested?
  33. 4 points
    dissolved oxygen Dissolved oxygen present in the boiler reacts with steel surface forming oxygen pits leading to corrosion.. It also flashes into steam and corrodes the whole piping system including condensate return line Hard water Presence of calcium and magnesium in higher concentration in water makes it harder called hardwater.. Reason being CA and MG are positively charged ions, if it present more, it will make it very difficult for the other salts to dissolve.. That's one reason soap in hard water wouldn't dissolve soon..
  34. 4 points

    Diesel Engine Vs Petrol Engine

    I think that the question is based on a false premise. It is not true that diesel engines categorically run at lower speeds than do petrol engines. That said, it is true that diesel engines usually involve very heavy (massive) components due to the high firing pressures involved, and the dynamic loading on such massive components at higher speeds is a severe problem. Recall that, at steady rotational speed, the dynamic loads vary with the square of the speed. Thus a massive diesel connecting rod, operating at 2000 rpm sees four times the dynamic loads that the same rod would experience at 1000 rpm.
  35. 4 points

    Automobile engineering Quiz 1

    Name: Automobile engineering Quiz 1 Category: Mechanical Engineering Quiz Description: Automobile engineering Quiz 1 Click here to take this quiz!
  36. 4 points
    If a floating body is given a small angular displacement and after the removal of that Force or moment, body comes back to its original position. It is called as Stable Equilibrium. For stable equilibrium of a floating body, the metacentre M must be above the centre of gravity G. In order to sustain stability, the Metacentric ht of any floating body must be positive.Greater the positivity of the metacentric height of a body, the greater stability it is able to attain. Also the center of gravity should be as minimum as possible. The conditions for stable equilibrium differs in case of submerged and floating bodies.It becomes more complicated when floating bodies are considered. Now as the body rotates responding to any disturbance the center of buoyancy can shift. This could render the body stable even though the center of gravity is above the center of buoyancy.
  37. 4 points


    All about centrifugal pump Pump performance curve system performance curve Friction loss Energy loss Pump selection pump design Fanning Diagram
  38. 4 points


    Classification of bearings Function of bearing 2 powerpoint presentation
  39. 4 points
    CRDI means Common Rail Direct Injection.. In crdi contains a small tube is called Common rail where the injectors are connected and contains fuel at a constant high pressure of 1,350 bars. The CRDI engine small amount of fuel into the engine before the actual charge and another one afterwords. the high pressure in common rail ensures that when it injected the fuel atomizes to a very high degree and mixes evenly with the air, thereby it making very clean exhaust gas. The engine pr. , timing of fuel injected is controlled ECU. The injectors have very precise dose of diesel into each cylinder .and ECU makes sure the fuel injected at optimum moment. "This ensures lower emissions, and allows better fuel economy.
  40. 4 points
    *GEARTURBINE PROJECT: Atypical InFlow Thermodynamic Technology Proposal Submission Innovative [TURBO-ROTARY] Novel (Fueled) Motor Engine Type -The Gearturbine comes from the contemporary ecological essential global needs of an efficient power plant fueled motor engine. -Power thrust by bar (tube); air, sea, land and power generation, work use application. *Have the similar simple basic system of the "Aelopilie" Heron´s Steam Turbine device from Alexandria, [10-70 AD] one thousand nine hundred years ago. Because; the circular dynamic motion, with 2/Two Opposites power [polar position] lever, and is feeds from his axis center. YouTube Video/10.30 min; * Atypical New · GEARTURBINE / Retrodynamic = DextroRPM=> VS <=LevoInFlow + Ying Yang Thrust Way Type - Non Waste Looses http://www.youtube.com/watch?v=0cPo9Lf44TE -Desirable Contemporary Innovation, With the Possible [Efficient] Invention. -Mechanical [Thermodynamic] Universal Human History Evolution. [unlike] Epic Technology Revelation. -Next Step Power-plant New Design Form Function Device Change. *8-X/Y Thermodynamic CYCLE - Way Steps: 1)1-Compression / bigger 2)2-Turbo 1 cold 3)2-Turbo 2 cold 4)2-Combustion - circular motion flames / opposites 5)2-Thrust - single turbo & planetary gears / ying yang 6)2-Turbo 2 hot 7)2-Turbo 1 hot 8)1-Turbine / bigger *Innovation Technology Break Barrier / Paradigm [broken-Seal] Solution. State of the art. Innovative Turbo-Rotary concept Top system. -With Retrodynamic Dextrogiro vs. Levogiro Phenomenon Effect. / Rotor-RPM VS InFlow / front=> to <=front; "Collision-Interaction Type" - inflow vs. blades-gear-move. Technical unique dynamic innovative motion mode. [Retrodynamic Reaction = When the inflow have more velocity the rotor have more RPM Acceleration, with high (XY Position) Momentum] Which the internal flow (and rotor) duplicate its speed, when activated being in a rotor (and inflow) with [inverse] opposite Turns. A very strong Novel concept of torque power thrust. At field explanatory example with a metaphor is like if a sailboat take the wind from his prow front to move; wind/inflow + knots/rpm + wind/inflow + knots/rpm + wind/inflow + knots/rpm + etc... = Acceleration x Acceleration = Exponential Acceleration. Whereas it has more movements forwards, it receives a frontal impulse still but to move more forwards. A present example of the implementation of the Retrodynamic effect is in the application in the accelerator (and collider) of particles that this in the border of Switzerland and France. -Shape-Mass + Rotary-Motion = Inertia-Dynamic / Form-Function Wide [Flat] Cylindrical shape + positive dynamic rotary mass = continue Inertia kinetic positive tendency motion / all the complete Rotary motor mass weight is going with the power thrust move circular direction. -Non-waste parasitic looses system for cooling, lubrication & combustion; -Lubrication & Combustion, inside a conduit radial position, out way direction, activated by Centrifugal Force-Fueled Injected. -Cooling; a) IN-Thermomix flow, & OUT-Air Thermo transference. -Combustion 2Two [inside-Rotary-Dynamic] continue circular [Rockets] flames. Like two dragons trying to bite the tail of the [ying yang] opposite other.-Increase the first compression by going of flow reduction of one big circumference blades going pass to 2TWO reduced, very long distance (total captive compression) INFLOW [inside propulsion] CONDUITS [long flow interaction] [like a digestive system] Start were ends, in perfect shape balance in perfect equilibrium well balanced, like a snake bite his own tale. -4 TURBOS Rotary [inside-rotary-active] [in-Flow, Out-Flow] Total Thrust-Power Regeneration [Complete] Power System. -Mechanical direct 2two [small] "Planetary Gears" at polar position. Like the Ying Yang Symbol/Concept. Wide out the Rotor circumference were have much more lever [HIGH Torque] POWER THRUST. -Military benefits, No blade erosion by sand & very low heat target profile.-3 stages of inflow turbo compression before combustion; 1)1-Turbine, 2)2-Turbos 3)2-Turbos. -And 3 points of power thrust; 1-flow way, 2-gear, 3-turbine. *The most innovative power plant motor engine project today. Higher efficient % percent. Next trend wave toward global technological coming change. Patent; Dic. 1991 IMPI Mexico #197187 - Carlos Barrera. - Individual Designer - Inventor and project owner. / All Rights Reserved. - Monterrey NL Mexico. Top Tech Tip Final Subject GEARTURBINE Project Documento.rtf
  41. 4 points
    if the Re<2000 then laminar flow ,,,,,,, Re>4000 then turbulent flow ,,,,,,,,,Re b/w the 2000-4000 then changing laminar to turbulent. (transition state)
  42. 4 points
    Wow... this is the topic where I would love to share my views........ Its one time or twice we get chance to be part of summer internship, we need to make sure...we make most of it.... if you do marks will be there always... As said by Rao Shahb, I agree with him... It looks that we would remember everything in our brains....and as such no diary is needed, but everything goes out of our brain when we are about to make our reports. Actually its not our fault, but our brain works like that.. With permission, I would like to add few points.... First I would like to say........ whenever you abt to start your internship....make sure you do literature survey, or ask your seniors........ about the company..... the manufacturing process they are into..........Quality concerns.......... new technologies available... And most important , read all mechanical engineering topics which can be handy to understand the process........ Secondly : When u start your internship make flow diagrams........ how the material moves............process to process, department to deptt.. Thirdly......... Make sure to ask questions......on the other hand... don't ask so much.......that the operators , engineers working there feel the heat. A balance is the need of the hour... Actually there is a special course "Research Methodology" which can be handy and for that even a new section started on the board http://mechanical-engineering.in/forum/index.php?showtopic=1311 Once again i appreciate the topic... hoping some others will come with their views. Regards Saurabh Jain
  43. 3 points
    To my knowledge Moment : it is the force applied to bend or rotate a body. Bending moment : amount of internal resistance offered towards bending. Torsion moment : amount of resistance towards twisting. Torque : it is the twisting or turning effect. Or it is the amount of force to twist or rotate a body.
  44. 3 points
    Mechanics Corner A Journal of Applied Mechanics and Mathematics by DrD, #20 © Machinery Dynamics Research, 2015 A Question of Stability Introduction The word stability in its several forms is widely used in nontechnical communication. A person whose life it highly consistent from day to day is said to have a stable life. When the political situation in a particular area appears to be unlikely to change, it is said to be stable. A person who is well balanced and unlikely to be easily provoked to anger is said to be a stable person. When the medical condition of a sick or injured person ceases to get worse, the person is said to be stabilized. A company on the verge of bankruptcy is said to be an unstable company. But what does the word stability mean in a technical context? Each of the foregoing examples hints at the technical meaning without really being explicit about it. A factor g = accel of gravity was missing in the potential energy expression. That is now corrected. Stability.pdf
  45. 3 points
  46. 3 points
    why it is easy to pick cotton of 20kg and hard to pick steel of 20kg?
  47. 3 points

    Where Will I Find A Job??

    Dear Anurag, It is vitally important for engineers to keep on learning throughout their lives. If you are looking for a job, you need to spend some time simply searching, but there is usually a lot of down time. It is wise to spend that down time learning something new. It is particularly helpful to try to learn about a new industry/new technology that you think may help you to market yourself. Good Luck! DrD
  48. 3 points

    Valve simulator

    Hi all, I'm searching for a valve simulator, where I can set the valve attributes and see the flow of water (water drops) according to a special code .... Any suggestions? Thanks in advance.
  49. 3 points
  50. 3 points

  • Create New...