superhydrophobic windshield

BY

Praveen Kumar B

Why Choose this project?

Principle

What is super hydrophobic coating?

Theory

Application

Make up

Estimate

1. To Bring in a new type of Windshield Glass into the Automobile World.

There has been no windshield without a wiper so far in

the automobile world. Bringing in this change will lead

to a new class of windshields without the presence of

wipers.

2. To reduce the usage of wipers which are prone to mechanical faults.

Wipers are the conventional method used for clearing away

rainwater of the windshield. But there are lot of loss and

accidents caused by faulty wipers.

As many as 1,40,000 2012 Ford Focus models are being

recalled because they could be at risk of an accident due to a

problem with their windshield wipers, according to the

National Highway Traffic Safety Administration (NHTSA).

3. To enhance the vision of drivers during rains and thus

reducing the chances of accidents due to improper

vision during rains. The visibility for the drivers is

reduced drastically due to the water droplet which are

adhered to the windshield, thus it scatters light making

it hard for the driver to see.

The lotus effect refers to the very high water repellence

(Super hydrophobocity) resulting in self-cleaning properties,

as exhibited by the leaves of the lotus flower. Dirt particles

are picked up by water droplets due to a complex micro- and

nano scopic architecture on the surface, which minimizes the

droplet's adhesion to said surface.

Hydrophobic properties have been seen in nature

since the beginning of time. Water droplets falling

onto plant leaves roll off the leaves as seen in the

photo below.

The process of coating the surface of a material with

hydrophobic property material in order to avoid

sticking of liquids on that surface.

This is absolutely unique way of coating unlike

conventional which shrink continuously during drying

to produce low porosity films

Super hydrophobic technology makes water bounce, it

stops it, rolls it off the surface.

Angle where water drop makes contact with the surface

Hydrophilic: θ < 90°

Hydrophobic: θ > 90°

Super hydrophobic: θ > 150°

CRITICAL ANGLE :-

Requirements of Super-Hydrophobic Surface

Super hydrophobic surfaces with a water contact angle (CA) greater than 150o

Requirements of Super-Hydrophobic Surface

advancing contact angle receding contact angleA R

Hysteresis H =A

_R

The contact anglehysteresis can be regarded asthe force required to move aliquid droplet across a surface.

Super hydrophobic surfaces with a low hysteresis

Small Hysteresis

Liquid droplet can roll off easily

Artificial Super-Hydrophobic Surface

Transformation of a SimplePlastic into a SuperhydrophobicSurface

30℃ 60℃

Super Hydrophobic Surface ofAligned Polyacrylonitrile Nanofibers

It can also be achieved by heating the surface by using some chemicals which exhibits superhydrophobicity.

Hydrophobic coatings are being used in many different areas:

• Aerospace

• Wood construction

• Monument protection

• Graffiti cleanup

Super-hydrophobic coatings can be made from many different materials.

The following are known possible bases for the coating:

•Manganese Oxide Polystyrene (MnO2/PS)

•Zinc Oxide Polystyrene (ZnO/PS) nano-composite

•Precipitated Calcium Carbonate

•Carbon nano-tube structures

•Silica nano-coating

The silica-based coatings are perhaps the simplest to use. They are gel-based and can be easily applied either by dipping the object into the gel or via aerosol spray.

The windshield is kept at 45 degree of inclination.

The super hydrophobic material is taken in the spray bottle and at particular melting point of the material it is heated and sprayed in the windshield.

Experimental glass - ₹ 1000

The various chemicals - ₹ 3000

Experimental setup - ₹ 1000

Testing & Experimentation - ₹ 5000.

Total - 10000

http://www.nsec.ohio-

state.edu/teacher_workshop/Superhydrophobicity.pdf

http://voh.chem.ucla.edu/classes/Superhydrophobic_Surface

s/pdf/Superhydro%20%20Presentation.pdf

http://en.wikipedia.org/wiki/Hydrophobic

http://www.wired.com/science/discoveries/magazine/16-

11/st_infoporn#

http://inventorspot.com/articles/fioravanti_sees_future_no_w

indsh_11050