Mechanical World

Today we will discuss about continuous variable transmission. We also discuss about advantages and disadvantages of CVT transmission.  Till now we know that we use gear box to change the torque according to the driving requirement. For this we have four to five gear ratio which we shift and change the gear. But CVT is an automatic transmission that can select any desired drive ratio within its operating range. Unlike a conventional four or five-speed transmission, CVT is an infinite speed ratio transmission. In the manual gearbox one problem facing that the one speed ratio is not fully efficient in the desire range. So the manufactures have to work on a new system which can obtain infinite speed ratio and there is one unique speed ratio for one speed. This is the basic idea of CVT.  Principle of CVT Transmission: As an ordinary gear box CVT also works on the same gearing principle that when we attached a big driving gear to one small driven gear we obtain high...

The next generation of aircraft could be thinner and lighter thanks to the development of a new imaging technique that could detect damage previously invisible to acoustic imaging systems. The nonlinear acoustic technique developed by researchers from the University of Bristol's Ultrasonics and Non-destructive Testing (NDT) research group is published in the current issue of  Physical Review Letters  together with an accompanying article in  Physics . It has long been understood that acoustic nonlinearity is sensitive to many physical properties including material microstructure and mechanical damage. The lack of effective imaging has, however, held back the use of this important method. Currently engineers are able to produce images of the interior of components using ultrasound, but can only detect large problems such as cracks. This is like detecting only broken bones in a medical environment. Imaging of acoustic nonlinearity is achieved by exploiting diffe...

For decades, battery storage technology has been a heavy weight on the back of scientific innovation. From cell phones to electric vehicles, our technological capabilities always seem to be several steps ahead of our ability to power them. Several promising new technologies are currently under development to help power the 21st century, but one small start-up looks especially well positioned to transform the way we think about energy storage. Texas-based EEStor, Inc. is not exactly proposing a new battery, since no chemicals are used in its design. The technology is based on the idea of a solid state ultra capacitor, but cannot be accurately described in these terms either. Ultra capacitors have an advantage over electrochemical batteries (i.e. lithium-ion technology) in that they can absorb and release a charge virtually instantaneously while undergoing virtually no deterioration. Batteries trump ultra capacitors in their ability to store much larger amounts of energy at a giv...

ABS Technology: Requirement of ABS Technology: We know that when we applied brake, it pushes the brake pad on running drum or disk. For heavy loaded vehicle we need to high braking force to stop of slow down the vehicle. This braking force generate by some means like hydraulic pressure, Air pressure etc. When the vehicle is running and we want to stop the vehicle we push the brake pedal. Due to excessive braking causes skidding. This skidding jam the wheel but due to inertia the vehicle tends to skid on the road and it became out of control from driver. This is called locking of the wheel. This is understood by that when we run on the floor and eventually tends to stop we slip down on it. This is exactly true for the vehicle. This type of locking is harmful for driving and may cause accident. So we have to remove it use of a new safety system. This system is called ABS. Working of ABS Technology: We have been already explained how locking of road wheels due to excessive b...

Low temperature combustion is a combustion concept that bears simultaneous reductions in pollutant emissions as well as fuel consumption. Homogeneous Charge Compression Ignition is perhaps one of the oldest forms of low temperature combustion. In this method, a homogeneous blend of fuel and air is compressed until it auto-ignites. Homogeneous Charge Compression Ignition pairs the high efficiencies of conventional diesel compression ignition combustion with the homogeneous low soot attributes of typical spark ignition combustion. Through higher levels of dilution with air or residuals, engine-out NOx emissions are kept low. Reference to these factors, Homogeneous Charge Compression Ignition has exhibited near zero NOx and soot emissions paired with efficiencies similar to conventional diesel combustion. Unfortunately, this approach is only achievable over a narrow, part-load operating range owing to lack of direct control over the start heat release rate. To provide control over...