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Discussion Starter #1
Hey fellow car lovers! New here, currently in school studying EE.
Over the past month or so, an idea for a high performance hybrid car has been slowly creeping up on me.

Think the 918 or BMW i8 and then proceed to completely forget about those two cars.

This is not a conversion but a design from scratch.
Body will be designed using mostly carbon fiber and aluminium.

I'm planning to design only using super/ultra caps instead of high performance Li-Ion batteries(more on how I plan to achieve this in a later post where I'll draft the entire concept, maybe add in some numbers).

Also, no IC engine, but reaction engine(s).
Maybe one of PBS Velká Bíteš's Turbojet aircraft engines.
There will be multiple(2 at the least).
In addition to generating power, the turbojets will be used to generate down force(in corners and straight lines) and thrust(in straight lines, coming out of corners) through efficient use of aerodynamics.

I have some crazy ideas for the suspension, breaks, wheels and even the lights but I'd like to save that for another post(the draft).

At the end however, these are all just intentions. The concept draft which I hope to complete within the month will also act as a feasibility study(once posted here for judgement) and will determine whether I can pull this off(the design) or if the idea was dead from the beginning.

I've set the time limit at 3 years to complete the powertrain, aero and chassis/body design and hope to run CFD studies on aero within a year and a half.

So, what do you guys think? Can you guys suggest some high performance AC motors I'd like to look at?
 

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Hi
If you are studying engineering you will know how to run some number!
Please do so

Ultracaps - check on energy to weight ratios (also cost to energy ratios)

Reaction engines
Think about the equations
Thrust = mass flow rate x exhaust velocity
power required (at 100% efficiency) = 1/2mass flow rate x exhaust velocity squared
You will find them to be incredibly inefficient!

Carbon fiber - unless you know exactly what you are doing you will end up with a heavier part for the same strength than using S glass
Aluminium - bonding aluminium to fiberglass is NOT a trivial task - it can be done but most DIY bonds fail in a couple of years

Design
A modern car design for mass production involves literally thousands of engineer man years

And finally - "Hybrid" - a hybrid is probably a factor of ten more difficult to do than either a battery car or an IC car

not trying to piss on your picnic but you need to do a bit more homework
 

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Discussion Starter #4 (Edited)
Sorry for the late reply guys, had to take a bunch of tests..

are you aware of Wrightspeed?

http://www.wrightspeed.com
This is great!
I like their turbines and inverters.
However, I hope to design my own powertrain.
I can use their model as a guide.
Good to know this is commercial.Thank you!

Hi
If you are studying engineering you will know how to run some number!
Please do so

Ultracaps - check on energy to weight ratios (also cost to energy ratios)

Reaction engines
Think about the equations
Thrust = mass flow rate x exhaust velocity
power required (at 100% efficiency) = 1/2mass flow rate x exhaust velocity squared
You will find them to be incredibly inefficient!

Carbon fiber - unless you know exactly what you are doing you will end up with a heavier part for the same strength than using S glass
Aluminium - bonding aluminium to fiberglass is NOT a trivial task - it can be done but most DIY bonds fail in a couple of years

Design
A modern car design for mass production involves literally thousands of engineer man years

And finally - "Hybrid" - a hybrid is probably a factor of ten more difficult to do than either a battery car or an IC car

not trying to piss on your picnic but you need to do a bit more homework
I haven't had time to look at caps in detail yet, been hitting the books hard on turbines. Theory is pretty dense but it looks quite interesting.

Books: [1]: Gas turbine engineering handbook, Boyce
[2]: Gas turbine theory, Herb
(found both at the library, like [1] better)

Actually, before the I run the thrust, I need to solve the basic powertrain and aero first.
The true purpose of the turbine is to run a generator and create some downforce while at it(underbody aero). The thrust only activates at max motor output(wheels).

Refer: The FAN car(Brabham BT46)
/\/\This car used a fan to create massive amounts of downforce. It raced with the fan only once in 1978. It won with a massive lead of 34 seconds :eek:
Imagine what can be achieved with a turbine(I find it hard to).

I made a mistake, I meant composites when I said carbon fiber. Material selection will be done after the structural design is complete. I expect the majority of the body to be designed with carbon fiber.

This is not intended for mass production.
Besides I just found out a concept similar to this has already exists(in concept).
The jaguar C-X75
The prototype however, ended up getting an IC engine :/
But they though about it, so it just might be possible.

And finally, this project is really just a fantasy of mine. I only hope to learn something at the end of this venture..
I'd like to specialize in power generation and turbines for my engineering degree and this project would nicely complement that, I believe.
 
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