Posted tagged ‘need’

SOLAR POWER IN CARS

September 10, 2011

solar-auto-carsSolar energy is one of the many renewable sources of energy that is used for fueling vehicles, running consumer products and for the efficient running of homes and business establishments. Solar power is harnessed with the help of solar cells and solar panels which are placed in the item that has to be powered.

The solar car is something that is envisioned to materialize in the future, with some countries already having solar cars racing across countries.
With this, it is proven that it is viable to indeed produce and manufacture solar power cars in bulk, in the near future so that everyone will soon own a solar power car.

Of course, once solar power cars are manufactured, it does not implicate that all other fuel sources for cars on highways will be removed. All that is done in solar power cars is the supplementation of traditional fuel with solar energy so that you save not only on your economy, but also save the environment in more ways than one every year.

The solar power cars that are used in races today run only on solar power, and thus look odd in appearance. This is because these cars are designed in such a way that they can collect maximum solar energy with which it is possible for the car to gain the required speed and desired efficiency.

The solar cells used in solar power cars are large, and usually cover the entire vehicle. However in case of commercial uses, solar cells are much smaller and designed so that the vehicle not only looks attractive, but is also efficient in its functioning. Solar cars can be used for short commutes in town as these cars can work only on solar energy.

The batteries found in the vehicle stores excess solar power so that this power can be used when solar power is not available on demand like on cloudy days and at nighttime. The engines found in these solar power cars are very much like the engines found in electric cars found today. In addition to this, the cars are lightweight, so that solar power can be used more efficiently.

At present, there are many types of solar power cars in the development stage today, which are also available for sale. However as these cars are in the developmental stage, the car is not available to the general public. With so many benefits found in solar power cars, its cost will not be much higher than the cost of the traditionally powered vehicles of today.

Another benefit of solar power cars is there is no hassle of stopping at gas stations for gas nor is there the need of getting worried of rising gasoline costs. With a solar power car, you save on the money that you would have otherwise have needed for buying fuel to run your car. In addition to this, with solar power cars you will be doing your bit in stopping global warming problems as there are no fuel emissions from solar power cars.

FAILURE ANALYSIS

August 23, 2011

01-tank-failure-failure analysis-visual examination-scanning electron microscopy-metallography-materials technology


• Why ?

As the standards of our industry rise due to increasing globalization and competition, there is an ever growing need for consistency and reliability. Breakdown of any unit, system or equipment is an avoidable and costly occurrence and must be prevented or minimized. Analysis of such failures becomes a resourceful and affordable tool in addressing such unwanted occurrences.

To establish whether the cause of component failure lay on:

a) Service conditions
b) Design considerations
c) Material and its specification
d) Improper processing and assembly procedures or
e)  Combinations of these.

01-RootCause-root cause analysis cycle-problem solving steps-avoidance of recurring problems

Only the real “Root cause” can ensure the effectiveness of corrective and preventive actions and avoid recurrence of failure.

01-CauseEffect-analysis-bottom up predictive-ishikawa - fishbone diagram-prediction analysis

• Stages Of Failure Analysis

1. Understanding and assimilation of background data and selection of samples.
2. Examination and documentation of the failed part by the following

1. Visual examination of parts, location (if necessary) and relevant photographs as well.

01-visual examination-metallographic examination-appearance of the parts-calibrated metallurgical microscope equipment-image analysis-microstructure

2.  Non destructive testing by means of Radiography, Dye      penetrant, Magnetic particle testing etc.

01-NDT-non destructive testing-cold process-radiography-die penetrant techniques-magnetic particle testing
3. Mechanical Testing for various physical properties.

3. Vital specimens are selected, classified, and subjected to:

  1. Macroscopic examination and analysis. This involves examining the fracture surfaces, secondary cracks, deposits and other such elements
  2. Microscopic examination and analysis of fracture surface (by Scanning Electron Microscopy, if required).

01-scanning-electron-microscopy-vital specimens-fracture surfaces-secondary cracks-microscopic examination

4. Chemical analysis of material for conformation to specifications.

5. Chemical analysis of corrosion products, deposits, contaminants etc.

01-corrodedmetal-corrosion in metals-material technology-material science and metallurgy-iron oxidization-low affinity with oxigen-electrochemical corrosion-oxidation

6. The actual state of the failed part and the failure mode are established.

7.  Fracture mechanics study if found necessary.

01-connection_failure_analysis-comprehensive failure analysis-analysis and testing-investigation of failure-design life check-failure mechanisms-identification of causes of failure
8. A simulation of the identical working environment to determine if any external      factors have contributed to the failure

9. Conclusions are determined after compiling all evidences and analysis and       then the report is generated.
10. Follow-up recommendations are also provided.

ULTIMATE ECO CAR

August 23, 2011

01-ultimate_eco_car-developments of hybrid technology-development of hydrogen fuel-fuel cell-hybrid technology

Continuous improvement in conventional engines, including lean-burn gasoline engines, direct injection gasoline engines and common rail direct-injection diesel engines, as well as engines modified to use alternative fuels, such as compressed natural gas (CNG) or electricity (for Electric Vehicle).

Engineers may disagree about which fuel or car propulsion system is best, but they do agree that hybrid technology is the core for eco-car development.


01-ultimate_eco_car-diesel hybrid-fuel cell vehicle-alternate fuel hybrid vehicles


“Plug-in hybrid” technology brings further potential for substantial CO2 emissions reductions from vehicles. It has a higher battery capacity and is thus more fuel-efficient than the current hybrid, assisted by the power of engine. For a short-distance drive, it could be run with electricity charged during the night. Depending on how electricity is generated, the vehicle could run with much lower CO2 emissions. In order to commercialize the plug-in hybrid, there is again a need for a breakthrough in battery technology. It is necessary to develop a smaller-sized battery with higher capacity. Plug-in hybrids could contribute to reducing substantial amounts of CO2 emissions from vehicles, as well as fossil fuel use, by charging from cleaner electricity sources in the future.

Challenges of increasing power performance

In order to improve the driving performance, its power train was completely redesigned. To increase motor output, a high-voltage power-control was adopted. Although this technology was used in industrial machines and trains, the idea of incorporating it into an automobile did not easily occur at first. First of all, the system itself would take up a substantial amount of space and secondly, there was no prior example of applying this method to a motor that switches between output and power generation at such a dizzy pace.

Once the development of the high-voltage power circuit began, there was a mountain of problems, such as what to do about the heat generated by increasing voltage and the noise generated. To reevaluate the power train, the project team had to produce prototypes and repeat numerous tests. The prototyping stage went to seven prototypes instead of the usual three, and the total distance driven by these prototypes during testing exceeded one million kilometers.

ULTIMATE ECO CAR

August 23, 2011

01-ultimate_eco_car-developments of hybrid technology-development of hydrogen fuel-fuel cell-hybrid technology

Continuous improvement in conventional engines, including lean-burn gasoline engines, direct injection gasoline engines and common rail direct-injection diesel engines, as well as engines modified to use alternative fuels, such as compressed natural gas (CNG) or electricity (for Electric Vehicle).

Engineers may disagree about which fuel or car propulsion system is best, but they do agree that hybrid technology is the core for eco-car development.


01-ultimate_eco_car-diesel hybrid-fuel cell vehicle-alternate fuel hybrid vehicles


“Plug-in hybrid” technology brings further potential for substantial CO2 emissions reductions from vehicles. It has a higher battery capacity and is thus more fuel-efficient than the current hybrid, assisted by the power of engine. For a short-distance drive, it could be run with electricity charged during the night. Depending on how electricity is generated, the vehicle could run with much lower CO2 emissions. In order to commercialize the plug-in hybrid, there is again a need for a breakthrough in battery technology. It is necessary to develop a smaller-sized battery with higher capacity. Plug-in hybrids could contribute to reducing substantial amounts of CO2 emissions from vehicles, as well as fossil fuel use, by charging from cleaner electricity sources in the future.

Challenges of increasing power performance

In order to improve the driving performance, its power train was completely redesigned. To increase motor output, a high-voltage power-control was adopted. Although this technology was used in industrial machines and trains, the idea of incorporating it into an automobile did not easily occur at first. First of all, the system itself would take up a substantial amount of space and secondly, there was no prior example of applying this method to a motor that switches between output and power generation at such a dizzy pace.

Once the development of the high-voltage power circuit began, there was a mountain of problems, such as what to do about the heat generated by increasing voltage and the noise generated. To reevaluate the power train, the project team had to produce prototypes and repeat numerous tests. The prototyping stage went to seven prototypes instead of the usual three, and the total distance driven by these prototypes during testing exceeded one million kilometers.

MAGNETIC BEARING TECHNOLOGY

August 22, 2011

01-Magnetic_Bearing-magnetic bearing technology-active non contact position sensors

Magnetic bearings have been utilized by a variety of industries for over a decade with benefits that include non-contact rotor support, no lubrication and no friction.

Conventional mechanical bearings, the kind that physically interface with the shaft and require some form of lubrication, can be replaced by a technology that suspends a rotor in a magnetic field, which eliminates friction losses.

01-floating rotors-magnetic bearing technologies-SKF compressor drive-advanced drive system

There are two types of magnetic bearing technologies in use today – passive and active.  Passive bearings are similar to mechanical bearings in that no active control is necessary for operation. In active systems, non-contact position sensors continually monitor shaft position and feed this information to a control system.  This in turn, based on the response commanded by the system, flows to the actuator via current amplifiers.  These currents are converted to magnetic forces by the actuator and act on the rotor to adjust position and provide damping.

Additional benefits of magnetic bearings include:

  • No friction
  • No lubrication
  • No oil contamination
  • Low energy consumption
  • Capacity to operate within a wide temperature range
  • No need for pumps, seals, filters, piping, coolers or tanks
  • Environmentally friendly workplace
  • Impressive cost savings

In practice, these attractions are balanced in order to maintain a gap between the shaft (rotor) and static parts (stator). The function of the magnetic bearing is to locate the shaft’s rotation axis in the center, reacting to any load variation (external disturbance forces),


01-typical examples for Floating rotors to run a heavy machineries-magnetic bearing systems to run shaft without friction

Floating rotors could boost compressor efficiencies

Traditional centrifugal compressors are based on low-speed drives, mechanical gears and oil-film bearings, resulting in high running costs because of their high losses, wear, and need for maintenance.

This new compressor drive (above) uses a permanent magnet motor, operating at an efficiency of around 97%, to drive a rotor “floating” on magnetic bearings, which spins the compressor impeller at speeds of around 60,000 rpm. These drives experience almost no friction or wear, and need little maintenance. They also minimize the risk of oil contamination, and result in compressors that are about half the size of traditional designs.


How they work

 

01-general-magnetic-principles-monitoring the air gap of shaft and bearings contact and position-position sensor-closed loop system-controlling of shafts in center position-position controller
Magnetic bearings are basically a system of bearings which provide non-contact operation, virtually eliminating friction from rotating mechanical systems. Magnetic bearing systems have several components. The mechanical components consist of the electromagnets, position sensors and the rotor. The electronics consist of a set of power amplifiers that supply current to electromagnets. A controller works with the position sensors which provide feedback to control the position of the rotor within the gap.

01-magnetic-5 axis shaft control-radial bearings-air gap- advanced bearing technologies

The position sensor registers a change in position of the shaft (rotor). This change in position is communicated back to the processor where the signal is processed and the controller decides what the necessary response should be, then initiates a response to the amplifier. This response should then increase the magnetic force in the corresponding electromagnet in order to bring the shaft back to center. In a typical system, the radial clearance can range from 0.5 to 1 mm.

This process repeats itself over and over again. For most applications, the sample rate is 10,000 times per second, or 10 kHz. The sample rate is high because the loop is inherently unstable. As the rotor gets closer to the magnet, the force increases. The system needs to continuously adjust the magnetic strength coming from the electromagnets in order to hold the rotor in the desired position.