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    ANSYS offers engineering simulation solution sets in engineering simulation that a design process requires. Companies in a wide variety of industries use ANSYS software. The tools put a virtual product through a rigorous testing procedure (such as crashing a car into a brick wall, or running for several years on a tarmac road) before it becomes a physical object. This pdf gives good start to understand and learn ANSYS
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    Dear Folks, Enjoy with useful Engineers pocket guide
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    This is one important point missing in the two previous answers. The "cc rating" of an engine is a volume measure, as previously stated, but it is not the actual cylinder volume. Rather, it is the swept volume of the cylinder, also called the "displacement" of the cylinder. The actual cylinder volume is always somewhat greater than this value because the piston at TDC does not leave zero cylinder volume. The small volume remaining at TDC is called the "clearance volume," the volume available for the early stage of combustion. DrD
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    Presentation on Design of- Clutch Brake Belts Chain Gears
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    Tips, advise and suggestions to engineers for a sucessful career path....& success in engineering profession
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    turbofan engine

    From the album Engines

    The turbofan or fanjet is a type of airbreathing jet engine that finds wide use in aircraft propulsion. As all the air taken in by a turbojet passes through the turbine (through the combustion chamber), in a turbofan some of that air bypasses the turbine. A turbofan thus can be thought of as a turbojet being used to drive a ducted fan, with both of those contributing to the thrust
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    What is Anti-lock braking system (ABS)? Anti-lock braking system (ABS) is an automobile safety system that allows the wheels on a motor vehicle to maintain tractive contact with the road surface according to driver inputs while braking, preventing the wheels from locking up and avoiding uncontrolled skidding. It is an automated system that uses the principles of threshold braking and cadence braking which were practiced by skillful drivers with previous generation braking systems. It does this at a much faster rate and with better control than a driver could manage. ABS generally offers improved vehicle control and decreases stopping distances on dry and slippery surfaces for many drivers; however, on loose surfaces like gravel or snow-covered pavement, ABS can significantly increase braking distance, although still improving vehicle control. How does ABS work? The anti-lock brake controller is also known as the CAB (Controller Anti-lock Brake). Typically ABS includes a central electronic control unit (ECU), four wheel speed sensors, and at least two hydraulic valves within the brake hydraulics. 1. The ECU constantly monitors the rotational speed of each wheel; if it detects a wheel rotating significantly slower than the others, a condition indicative of impending wheel lock, it actuates the valves to reduce hydraulic pressure to the brake at the affected wheel, thus reducing the braking force on that wheel; the wheel then turns faster. Conversely, if the ECU detects a wheel turning significantly faster than the others, brake hydraulic pressure to the wheel is increased so the braking force is reapplied, slowing down the wheel. This process is repeated continuously and can be detected by the driver via brake pedal pulsation. Some anti-lock systems can apply or release braking pressure 15 times per second. Because of this, the wheels of cars equipped with ABS are practically impossible to lock even during panic braking in extreme conditions. 2. The ECU is programmed to disregard differences in wheel rotative speed below a critical threshold, because when the car is turning, the two wheels towards the center of the curve turn slower than the outer two. For this same reason, a differential is used in virtually all roadgoing vehicles. 3. If a fault develops in any part of the ABS, a warning light will usually be illuminated on the vehicle instrument panel. What is Electronic brake-force distribution (EBFD)? You’re driving at a safe speed on a moderately busy highway. It has not been snowing for long, but already the pavement is dusted with snow and becoming slippery. Suddenly, another motorist signals to enter your lane and makes a sharp veering motion. You are forced to slam on the brakes to avoid hitting the encroaching vehicle. The weight of your car is thrust forward from the heavy braking, putting added pressure on the front wheels to stop the car. Meanwhile, the sudden shift in weight has significantly reduced the amount of traction available for the back wheels. After a few seconds, the back wheels lock completely. You feel the back end of your car start to fishtail into the lanes on either side of you. Finally, the back-and-forth motion of the rear of the car overcomes the braking power of the front wheels and you spin around, face-to-face with oncoming traffic. Situations like this are potentially very dangerous. Electronic brake-force distribution is a vehicle safety feature that can prevent this kind of event. How does EBFD work? 1. Electronic brake-force distribution is often installed with antilock braking systems (ABS). ABS installations that are supplemented with EBFD react more quickly and deliver more situation-specific braking commands than older ABS setups. 2. EBFD systems are usually made up of three subcomponents that are monitored and guided by an electronic control unit (ECU). These components include speed sensors for each wheel (sensors that monitor how fast the wheel is rotating), brake-force modulators (a mechanism that increases or decreases brake-force applied to a wheel), an acceleration / deceleration sensor that detects the vehicle’s forward and sideways acceleration/deceleration, and usually a yaw sensor (a sensor that monitors a vehicle’s movement along its vertical axis). 3. The electronic control unit interprets the information from the speed and yaw sensors, and then sends commands to the brake-force modulators. Similar to how ABS setups operate; the ECU in EBFD systems is attached to the hydraulic brake-force modulator. So, while the ECU and brake modulator serve different purposes, they are physically combined into one electro-hydraulic unit. 4. EBFD works by monitoring each wheel’s responsiveness to the brake, and then tailoring the amount of brake-force applied to each wheel. In vehicles without EBFD, when you apply the brakes the brake-force is evenly distributed across all four wheels. The danger here is that if, for example, one of your wheels is on ice and locks up, you lose 25% of your braking power. On a vehicle with EBFD, the system would sense that one of the wheels is not braking properly, and would redistribute the brake-force to the unaffected wheels to obtain optimal braking power. This way, you retain the maximum amount of braking power possible and reduce the risk of fishtailing or spinning around. 5. The yaw sensor installed with most EBFD systems also helps prevent oversteering and understeering. Oversteering occurs when a vehicle continues to turn beyond the steering input of the driver, while understeering refers to cases where the vehicle does not turn enough in response to driver commands. Both oversteering and understeering are the result of insufficient traction on the road. If you begin to oversteer or understeer, the yaw sensor will record unusual movement along the vehicle’s vertical axis, and your EBFD system will react by applying either the brakes on the inner wheel (to correct understeering) or the brakes on the outer wheel (to correct oversteering).
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    Saurabh, your comment about the quality of the English concerns me also. When you go to their web site, the English there is similar. These folks really need help in that respect. I am also concerned about the stated breadth of topics for this journal. It includes everything from history, to geology, to economics, and on to mathematics. I have reservations about how one journal can adequately cover such a broad scope. DrD
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    Ravi, I think you may be in over your head! What do you mean by the term "resting time"? Just a hint: Perpetual motion defies the second law of thermodynamics, and consequently cannot work. You are spinning your wheels (literally)! DrD
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    Quite a few interesting comments on reasons for design failure. Thank you JAG in particular. I would like to tell a story about a failure that I saw once long ago that was somewhat different. It involved a design that had been developed in a government laboratory, manufactured in very small quantities with tight controls for testing, and then put out to industry for mass production. In order to bring the unit price down, the government arbitrarily specified rather loose tolerances, far more loose than anything that had been allowed in the development phase. But then, the government added a performance specification, that the product must function according to design. The result was that the mass production companies were bidding, based on nothing more than the drawings and specifications. It was implicit in the drawing package that a product made according to the drawings was expected to meet the performance specifications, and this was the way the bids were developed. My company was unfortunate enough to win the bid. We found through bitter experience that it was entirely possible to build the product according to the drawings but still fail the performance test at the end. This resulted in massive amounts of rejected products. My job was to show mathematically that this was entirely possible, that the loosened tolerances allowed for performance failure. This was a failure driven by a desire to reduce costs to the purchaser. The result was the destruction of my employer; a company with over 100 years experience in the field was driven to bankruptcy. DrD
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    • Graded Mode
    • 5 minutes
    • 10 Questions
    • 24 Players
    Questions on the concepts of automobile engineering.
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    View this quiz Automobile Engineering Quiz 1 Questions on the concepts of automobile engineering. Submitter saurabhjain Time 5 minutes Type Graded Mode Submitted 04/20/2017 Category Automobile Engineering  
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    It is helpful to have specifications for the job that the design will accomplish to start with, it is then good to run FEA to validate the design. FEA can be a valuable tool if the proper and accurate data is entered into the program. I add a Factor of safety of at least 20% for my comfort but I frequently overbuild when I design production machines used in house where there is no issue with weight. A wise engineer once told me "You will be criticized for a design that fails long before being criticized for one that was too strong." When designing a product that has to be lightweight, I still overbuild at first and then find ways to lighten it as I refine the design. Personally I like to see multiple prototypes physically tested to extreme failure and the data collected, analysed and compared to customer requirements, I do not feel comfortable passing off a design that has not undergone a battery of testing. One of the reasons that I have seen designs fail is lack of experience.....education should include practical experience and application. Just because one has a degree from a university doesn't mean one is a competent engineer, I have worked with many green engineers who couldn't design their way out of a wet paper bag and were too proud to admit that they might not know something. In my opinion, engineers who ask more questions before designing a product, build better products in the end. Don't let your ego get the best of you! Also I believe it is extremely helpful to know as much as you can about the process or system that you are designing for, play production worker for a week if you can, you will gain valuable insight and gain allies on the production floor, both can be invaluable! Participating in design reviews can be a valuable resource. Remove yourself from your ego and listen to what your colleagues have to say and don't be so invested in your own ideas that you do not hear the other ideas in the room. Many heads have many ideas and combining ideas is a great way to make great designs. Lastly, dare greatly! Failure is part of life! Learning what doesn't work is how you work toward discovering what does! Do not let fear of failure inhibit your education, make your best design and try it, when it fails refine it, if it fails again, refine it again and try not to repeat the same mistakes. If you study the history of any great invention you will usually find a string of failed experiments that lead to a great discovery and a person who learned from their failures. Your failure will only define you if you let it.
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    As an engineer - How you will use Iron carbon diagram for analysis and decisions ? 1. You can answer this question. 2. You can like the best answer. 3. You can share the question Attach image Iron-carbon phase diagram under atmospheric pressure This diagram is limited by pure iron on the left and by iron carbide on the right. The mains phases are: α iron: ferrite, ferritic steel γ iron: austenite, austenitic steel iron carbide: cementite, Fe3C. We can see a eutectic and a eutectoid; these phases crystallize as a stacking of fine strips of pure phases (iron and cementite) in case of the eutectoid, or a pure iron containing small balls of cementite for the eutectic. Although it is heterogeneous, these phases behave like homogeneous pure bodies. Steel is between 0 and 2.06 mass percent of carbon. Cast iron is between 2.06 and 6.67%.
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    To my mind, this quiz focused on mostly the wrong things. These are, for the most part, things that can easily be looked up in a design manual or a handbook. A much more interesting quiz would focus on the understanding and application of idea, the ability to correctly model systems, and the ability to understand and correctly interpret data. DrD
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    It is certainly possible that links 2 and 4 have the same length. However, it is not necessary for this to be true. If L2 = L4, that is a special case. Whatever sort of project can you make from this super simple mechanism? DrD
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    Dr. D’s story reminded me of two related stories, then another and then another...but I will stop with two. The follow appeared in the Wall Street Journal 15-20 years ago. The happy ending was that the supplier finally won the court case against the US government. The unhappy part of the story, was that it cost the company much time and money. The article went on to say that a lot of companies go bankrupt from similar situations, but I digress. The government contracted with a commercial supplier to produce a device. The full-up device had a performance specification. The government was to provide the power supply that would be part of the final product. The government was never able to provide a power supply that met the government's own specifications, yet the government expected the supplier to provide an end item that was to specification, using an out of specification power supply. Only a government could keep a straight face and insist this made any sense. The other example can be found at the link below, titled What do you mean you made it as we told you to? https://www.linkedin.com/pulse/what-do-you-mean-made-we-told-joseph-a-gulino-pe?published=t At the above LinkedIn site you will find other articles by me.
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    For a journal bearing surface, it is obvious that a circular surface is essential; a square section in a square hole would not turn. A square section in a large round hole would have contact at 4 points at most, very little load bearing area. If we are going to use a circular section at a bearing, then there is no point at all to using a square section between the bearings. A square section would be heavier, and only a slight bit more stiff. The square section would require more material for no real benefit. Square or other polygon shapes are used for special situations, but only where the is an evident advantage in doing so. DrD
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    In the interest of being more accurate, I would ask more questions in regard to the question: Is there a specific application where designs are failing that you are referring to? As I have been thinking on this subject it occurred to me that some products are designed to fail as a means to create repeat business I.E. the auto industry is replete with examples of this where parts and material are selected to meet a predetermined somewhat predictable life cycle with cost constraints in place, #1 because wear is inevitable #2 materials that wear longer are generally more expensive and may price a product out of the market. Needless to say If your product never fails or wears out, you may eventually saturate your market, or your product may be too expensive to reach a broader customer base. In this respect product design is a balancing act between longevity, vs. price constraints vs. customer expectations vs. marketability etc. All of these things come into play as well as the fact that there is no way to control all of the outside factors that a product will be influenced by such as lack of maintenance, misuse and or abuse, adverse conditions etc. This brings to mind the questions: Is the product performing to the design intent? Is the product performing it's task for a reasonable life cycle? If the product fails due to lack of maintenance are you considering that a design failure? In my opinion if you can answer yes to the first two questions then you have met your design objective. Once a product is put on the market and into use you will inevitably discover that there are situations that arise that were not anticipated by the original design and a refinement must be implemented to meet the criteria of a new set of parameters, this is just a reality of engineering. The key is to develop short feedback cycles into your processes so that you can discover and solve problems quickly. I find it very effective to ask for customer feedback quickly and to respond to it quickly in order to develop an enduring relationship, and all customers are important whether it be your co-workers or end users, a satisfied customer is the ultimate test of any design!
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    i have to say in any branch of knowledge practice is very important that only sharpens - see as lawyers we use incisive questions besides again revisit with further interagations why, then only you can do real research on the problems - in law we ask too many questions even our own clients, to get at the heart of the issue, that is what we call sensible designing to progress further to ensure whether our client can really convince his stand with the judges....that is also called dynamic designing,
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    In most of the products made as per design need some modifications after the product has been practically tried and this can not be termed as failed design Also,a perfectly designed machine may fail during use due to number of other related factor such as operational parameters like pressure,temperature,environment,load,speed.Also,it must be ensured that the personnel operating the machine have got necessary technical skills. In short,before declaring a failed design,thorough analysis must be carried out to pin point the cause of failure.
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    These two concepts are not related the way you evidently think that they are. An aircraft is in accelerated flight when it flies a horizontal circle. That does not cause any increase in lift at all. If you think in terms of straight line flight, then yes, flying faster will produce more lift. If you want to go faster but no higher, you adjust the trim tabs, modifying the airfoil to reduce the increased lift. DrD
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    Dear All, Please explain about ASR and BSR. Also explain what is required to do before fill welding or after root weld???
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    This is a very poor English for a publication representative
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    What are the appropriate topics for a paper? Are there publication fees? Is it open access? Where is this journal published and who sponsors it? Here is is nearly the end of July and you are asking for papers for an August edition? How does that work? Is there peer review? There are a lot of unanswered questions that you need to address. DrD
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    Dear Daniel, You ask "What is the name of this mechanism?" but your videos/pictures show many mechanisms in action. Just which part are you asking about? Most of this looks like cam driven motions, with a follower moving in a vertical guide while the cam drives the follower up and down. Please describe your interests in more detail so that we may try to give a better answer. DrD
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    Hello, Im interested in that Can you share? Thank you so much!
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