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How Cruise Control Systems Work

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            Cruise control is an invaluable feature on American cars. Without cruise control, long road trips would be more tiring, for the driver at least, and those of us suffering from lead-foot syndrome would probably get a lot more speeding tickets. What It Does:- The cruise control system actually has a lot of functions other than controlling the speed of your car. For instance, the cruise control pictured below can accelerate or decelerate the car by 1 mph with the tap of a button. Hit the button five times to go 5 mph faster. There are also several important safety features -- the cruise control will disengage as soon as you hit the brake pedal, and it won't engage at speeds less than 25 mph (40 kph). The system pictured below has five buttons: On, Off, Set/Accel, Resume and Coast. It also has a sixth control -- the brake pedal, and if your car has a manual transmission the clutch pedal is also hooked up to the cruise control.               The on and off butt

RESISTANCE OF SHIP

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            Resistance of ship is the opposing force experienced by the body while moving through liquid. Types of Resistance:- 1. Wave making resistance 2. Frictional resistance 3. Viscous pressure drag 4. Eddy making resistance 5. Appendage resistance 6. Wind making resistance Methods to find resistance:- l) From model test      - done in towing tanks     - models attached to the carriage     - platform has a dynamometer from which resistance is measured     - resistance tests are done in smooth water 2) From methodical series        - test starts with a parent form        - a number of significant form parameters are varied        - results show how resistance varies with form parameters        - useful for estimating power for new designs Different methodical series      - Taylor series      - BSRA series      - Gulhammer & Harward series      - DTMB series Using Gulhammer & Harward series Step 1:-    Residual resistance coefficient and frictional resistance coefficient

FLOODABLE LENGTH OF SHIP

  WHAT IS FLOODABLE LENGTH?                     Floodable length at any point along the length of the ship is the length of the compartment with that point as center, which can be flooded without immersing any part of the margin line when the ship has no list . Need of Floodable Length:- 1. To fix compartment length 2. To fix compartment position

What is key role of designers and engineers in product life cycle?

  What is key role of designers and engineers in product life cycle?       This has been a common query which had been asked repeatedly. Since its a need, i am liable to answer the same since i had been working for a pretty long time in similar background. Designers and engineers are inolved in managing the CAD files.           There are wide varieties of plm softwares in the market which includes teamcenter, windchill, ennovia etc. Besides the point whichever plm software CAD designer is using. He will be involved in creation of products and modifying them in different stages using different CAD softwares. Please check out my  link related to different  stages of product:- Different stages of product        CAD designers need to be concerned more about design softwares compared to PLM, since they have to mange CAD files using PLM. Engineers use to manage different stages of product which involves mainly engineering change management and promotion request(for promoting cad files from o

LIFECYCLE OF PRODUCT

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               Every product which comes into the market comes with a particular life. The life which i am mentioning is not the expiry date which is labelled in the product. This topic is related to the stages of production which the product undergoes from birth to end of the product. No matter whichever product it may be as for example car, bike, engine, filter or a small cover come with a life. Every product will be remain in market until there is a demand for it. There are basically five stages in a product life cycle. Scratch or Development from Existing Product:-                            This is the initial stage of a product. The need of the customers is being analysed by various companies of specific field through market research. After analysis, they decide the type of product to be launched in the market. Creation of product is done mainly in two ways either by starting from the scratch by knowing the application or by modification of an existing product. In th

Difference between Power and Torque

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   One of the attached file shows a bike specification, in which you may see a red box marked under torque and power. Why Max power and Max torque has to be mentioned separately even though we know that power is dependent on torque? Here’s the answer:- There has been a common formula that is used for finding power of engine:-               Power = 2 x N x Ʈ / 60000,                                                   Where    Ʈ  =  Torque produced (units in Nm), N= speed of the engine (units in rpm), Power produced (units in watts divide by 746 to get hp or ps)       This relation holds well till the point of intersection of curves for torque and power, since until that point both torque and power kept on increasing together. After this point, the torque decreases but power keeps on increasing until a certain limit since power is also dependent on speed also and then power starts decreasing.                                         Torque of the engine d

OCTAHEDRAL SHEARING STRESS THEORY

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OCTAHEDRAL SHEARING STRESS THEORY                       According to this theory, the critical quantity is the shearing stress on the octahedral plane. The plane which is equally inclined to all the three principle axes is called the octahedral plane. τ oct = (1/3) [(σ 1 – σ 2 ) 2 + (σ 2 – σ 3 ) 2 + (σ 3 – σ 1 ) 2 ] 1/2                                                                                        where, τ oct = octahedral shearing stress Failure is said to occur when τ oct = ((√2)/3) σ e            This theory holds feasible for ductile materials and is similar to Von Mises theory.