librankur

CNG Cylinders - Whats with the shape and its placing

5 posts in this topic

Just saw the CNG Honda City pictures and this got me thinking

If a vehicle is going CNG does it still make sense to have a normal sized Petrol tank for it , should not the size of the petrol tank be reduced to accommodate the CNG Cylinder in that space, to free up boot space.

I would suggest to have the CNG tank in place of the petrol tank and just have a 5 ltr jerry can in the boot to hold Petrol or even two of them, one on both sides of the boot to balance it out. :)

Also , why a Cylindrical shape is the preferred choice of manufacturers , why arent other shapes being tried on , like what Wagon R did ,

i personally would love to see a U shaped cylinder,like the backrest of a sofa , an inversed U cylinder , placed horizontally could free up some space in boot of a sedan and a U shaped cylinder placed vertically could do the same on a small hatch

Hoping its nothing to do with cost cutting or OEM only suppy them in that shape and now we have plenty of CNG filling stations so that reason should also be out of the picture.

Better still give buyers a choice of what size tanks of both CNG and petrol they what where, based on their driving environment. may be a bit radical but doable

Share this post


Link to post
Share on other sites

Those are some very interesting points there librankur. The Wagon R tanks a good thing but that had the spare tyre go into the boot but I agree that took less space than the CNG tank. The U shaped idea seems very innovative for sure. With more people opting for CNG these days its time for manufacturers to start thinking out of the box to give a sizable CNG tank and yet not compromising on boot space.

Share this post


Link to post
Share on other sites

Just saw the CNG Honda City pictures and this got me thinking

If a vehicle is going CNG does it still make sense to have a normal sized Petrol tank for it , should not the size of the petrol tank be reduced to accommodate the CNG Cylinder in that space, to free up boot space.

I would suggest to have the CNG tank in place of the petrol tank and just have a 5 ltr jerry can in the boot to hold Petrol or even two of them, one on both sides of the boot to balance it out. :)

Also , why a Cylindrical shape is the preferred choice of manufacturers , why arent other shapes being tried on , like what Wagon R did ,

i personally would love to see a U shaped cylinder,like the backrest of a sofa , an inversed U cylinder , placed horizontally could free up some space in boot of a sedan and a U shaped cylinder placed vertically could do the same on a small hatch

Good suggestions! Auto-manufacturers should think on it!

Share this post


Link to post
Share on other sites

Why the LPG/CNG/Gases are stored in Cylindrical/Sperical tanks ??

Ans to this query: Because it's stored under pressure, all pressurised gas containers are cylindrical or spherical to eliminate corners which would be the weakest point.

---------------------------------------------------------------------------------------------------------

A sphere is a very strong structure. The even distribution of stresses on the sphere's surfaces, both internally and externally, generally means that there are no weak points. That's why a drop of water forms a spherical shape when under free fall, in short, it achieves a shape where all the resultant stresses neutralize when no external force(gravity) is acting on it. Moreover, they have a smaller surface area per unit volume than any other shape of vessel. This means, that the quantity of heat transferred from warmer surroundings to the liquid in the sphere, will be less than that for cylindrical or rectangular storage vessels. Thus less pressurization due to external heat.

Share this post


Link to post
Share on other sites

Only LPG storage tanks are offered in Toroidal shaped circular tanks in Wagon R/Santro/Spark, as shown in the pic below,

post-67-0-66421900-1350329588_thumb.jpg

While all CNG cars(even buses, etc) in India till to date are offered by OEM tank manufacturers are provided with conventional Cylindrical tanks.

post-67-0-70389600-1350329539_thumb.jpg

(Pic source: Company website for top pic & TAI for bottom pic)

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now