08-03-2011, 04:46 PM
Presented By:
Aatika Shahwar )
Ayushi Agarwal
Kirti Mishra
[attachment=9812]
POWER DRESSING
EVER THOUGHT??
INTRODUCTION
‘Smart Clothes’ woven with PVDF (polyvinylidene fluoride) nano fibers can power hand-held electronics.
The nano-sized generators with piezoelectric properties have the ability to transform energy from mechanical stresses, stretches and twists into power.
Environmental sensors incorporating the fibers gather energy from their surroundings and don’t need to rely on finicky solar power.
NANOFIBER GENERATORS
The researchers have created nanofibers, generating electrical outputs ranging from 5 to 30 millivolts and 0.5 to 3 nanoamps.
The tiny nano generators have diameters as small as 500 nanometers which makes it small enough to be woven right into clothes with no perceptible change in the user’s comfort.
There is no noticeable degradation after stretching and releasing the nanofibers for 100 minutes at a frequency of 0.5 hertz (cycles per second).
The energy efficiency ratings of the nanofibers are much greater than 0.5 to 4 percent achieved in typical power generators made from experimental piezoelectric PVDF thin films.
Multiple dips in the washing machine won't hurt as the fibers are flexible and resistant to heat and chemicals.
ENERGY AVAILABLE
The average adult consumes approximately 2000 kcal per day, equivalent to 100 W.
This power is expended during everyday activities, most significantly in fuelling the motions of walking, arm swinging, finger motion, and breathing.
This power acts as the main input for charging portable electronic devices.
The heel strike from walking is a particularly rich source of energy with 67W of power available from a brisk walker.
PIEZOELECTRICS
Piezoelectrics become electrically polarized when subjected to mechanical stress.
In response to this they experience a strain to an applied electric field in proportion to the strength of the field.
They contain no movable parts or complex assemblies & are a compact alternative to biomechanical power generation.
Piezoelectrics such as lead zirconate titanate (PZT) and the polymer polyvinylidene fluoride (PVDF) have been located inside the soles of shoes.
Piezoelectric materials generally fall into two classes: 1. Piezoelectric polymers
2. Piezoelectric crystals
The piezoelectric property of PVDF arises from the strong molecular dipoles within the polymer chain, combined with short- or long-range ordering.
The most important parameter for characterizing the efficiency of piezoelectric materials is the piezoelectric charge constant “d”.
The piezoelectric with the largest piezoelectric charge constant will yield the most optimal results in terms of energy conversion efficiency.
This value represents the polarization generated per unit of mechanical stress applied to a piezoelectric material.
EQUATIONS
The following linear equations describe the mechanical and electrical conversion in piezoelectric materials:
After the piezoelectric element is stressed, charge is generated at the surface perpendicular to the stress direction.
HYBRID NANOGENERATORS
The nano fiber generators comprising solely of PVDF are not very efficient as their piezoelectric charge constant d is as less as -25 pC / N.
Its efficiency can be enhanced using the following configurations:
o Piezoelectric polymer-based generators
o Piezoelectric nanowire-based generators
o Piezoelectric fiber composites
ELECTROSPINNING
This technique is used to create and position the polymeric nanogenerators in a grid pattern.
It helps to align the NG properly
This ensures placement of positive and negative poles on opposite ends, thus increasing energy efficiency.
(a) PFC fiber with IDE
SCOPE
Incorporating the advantages of high conversion efficiency, scalable manufacturing, and facile integration strategies, PVDF nanofiber power generators provide the basis for :
1. Structural Health Monitoring systems
2. Vibration Damping Systems
3. Self-powered textiles
4. Large area fabrics for Portable Electronics
5. Embedded power sources for nanodevices
Aatika Shahwar )
Ayushi Agarwal
Kirti Mishra
[attachment=9812]
POWER DRESSING
EVER THOUGHT??
INTRODUCTION
‘Smart Clothes’ woven with PVDF (polyvinylidene fluoride) nano fibers can power hand-held electronics.
The nano-sized generators with piezoelectric properties have the ability to transform energy from mechanical stresses, stretches and twists into power.
Environmental sensors incorporating the fibers gather energy from their surroundings and don’t need to rely on finicky solar power.
NANOFIBER GENERATORS
The researchers have created nanofibers, generating electrical outputs ranging from 5 to 30 millivolts and 0.5 to 3 nanoamps.
The tiny nano generators have diameters as small as 500 nanometers which makes it small enough to be woven right into clothes with no perceptible change in the user’s comfort.
There is no noticeable degradation after stretching and releasing the nanofibers for 100 minutes at a frequency of 0.5 hertz (cycles per second).
The energy efficiency ratings of the nanofibers are much greater than 0.5 to 4 percent achieved in typical power generators made from experimental piezoelectric PVDF thin films.
Multiple dips in the washing machine won't hurt as the fibers are flexible and resistant to heat and chemicals.
ENERGY AVAILABLE
The average adult consumes approximately 2000 kcal per day, equivalent to 100 W.
This power is expended during everyday activities, most significantly in fuelling the motions of walking, arm swinging, finger motion, and breathing.
This power acts as the main input for charging portable electronic devices.
The heel strike from walking is a particularly rich source of energy with 67W of power available from a brisk walker.
PIEZOELECTRICS
Piezoelectrics become electrically polarized when subjected to mechanical stress.
In response to this they experience a strain to an applied electric field in proportion to the strength of the field.
They contain no movable parts or complex assemblies & are a compact alternative to biomechanical power generation.
Piezoelectrics such as lead zirconate titanate (PZT) and the polymer polyvinylidene fluoride (PVDF) have been located inside the soles of shoes.
Piezoelectric materials generally fall into two classes: 1. Piezoelectric polymers
2. Piezoelectric crystals
The piezoelectric property of PVDF arises from the strong molecular dipoles within the polymer chain, combined with short- or long-range ordering.
The most important parameter for characterizing the efficiency of piezoelectric materials is the piezoelectric charge constant “d”.
The piezoelectric with the largest piezoelectric charge constant will yield the most optimal results in terms of energy conversion efficiency.
This value represents the polarization generated per unit of mechanical stress applied to a piezoelectric material.
EQUATIONS
The following linear equations describe the mechanical and electrical conversion in piezoelectric materials:
After the piezoelectric element is stressed, charge is generated at the surface perpendicular to the stress direction.
HYBRID NANOGENERATORS
The nano fiber generators comprising solely of PVDF are not very efficient as their piezoelectric charge constant d is as less as -25 pC / N.
Its efficiency can be enhanced using the following configurations:
o Piezoelectric polymer-based generators
o Piezoelectric nanowire-based generators
o Piezoelectric fiber composites
ELECTROSPINNING
This technique is used to create and position the polymeric nanogenerators in a grid pattern.
It helps to align the NG properly
This ensures placement of positive and negative poles on opposite ends, thus increasing energy efficiency.
(a) PFC fiber with IDE
SCOPE
Incorporating the advantages of high conversion efficiency, scalable manufacturing, and facile integration strategies, PVDF nanofiber power generators provide the basis for :
1. Structural Health Monitoring systems
2. Vibration Damping Systems
3. Self-powered textiles
4. Large area fabrics for Portable Electronics
5. Embedded power sources for nanodevices
