Hybrid engine stirling + + generator

[orbs]

Hello
Unless I am mistaken, basically we can write:
the hybrid engine combines a heat engine with a reversible electric motor as a generator. during the regenerative function, thermal power is borrowed in order to recharge the batteries (recharge increased by recovery during engine braking) therefore reduced energy efficiency.

allow the following hypothesis:
knowing the loss of heat by combustion of the hydrocarbon, it can be used to heat a stirling, this one causes the generator / engine at constant load; with the added bonus of heat storage, the stirling will consume the engine off.
What do you think?
please
@+
orbs

[wirbelwind262]

Hello
a quick question, Orbs,
why keep the internal combustion engine (considering the losses ....)?
as for thermal storage, it is unrealistic for a vehicle, moreover the stirling costs horribly expensive for a decent yield ...
in the end, your system may be extremely expensive (manufacture, purchase, etc ...), look for a system with the least possible energy conversion, it minimizes losses and it avoids "gas factories"
Good luck !

[Olivier22]

I think the idea is worth exploring!
Obviously, the Stirling must still be crated ...
Heat engine + stirling engine + generator + batteries + electric engine (s)!
You quickly arrive at a 2-ton city car!

But at the same time, we can reduce the size of the motors.
Let's say we want to get 50 kW at the wheels.
-With a simple thermal engine with an average efficiency of 30%, it is therefore necessary to consume 167 kW (equivalent) of fuel

- Same with a hybrid thermal + electric system (since all the energy comes from the thermal at the start - without taking braking recovery into account)

-With a thermal (30%), a medium stirling (30%) which is exposed to 80% of the heat lost by the engine, actuating a generator (90%), which drives a motor (90%) (in direct supply , shunted batteries):
So we have a return of 0,30+ (0,80x0,30x0,90x0,90) = 0,49
It is not extraordinary but it is correct.
As a result, we only consume 102 kW equivalent of fuel for 50 kW at the wheels.

Coupled with braking recovery, we should easily go to 55 or even 60%

The lack of flexibility of the Stirling modifies these calculations a little, but on an average I think it is a correct estimate

The big problem is that a stirling works well with a big delta T, so you need a very ... hot hot spring
It is not with the 80 ° C of a normal cooling circuit that we will get there ...
Look for a coolant with low thermal capacity, a high flow circuit and large exchange surface, ending with a passage on the exhaust manifold.
(We could perhaps reach 300-400 ° C by a cylinder circuit -> cylinder head -> manifold ... It remains weak for a stirling, hard to reach 30% with that !! I don't even know if it is. is possible)
The only solution is forced gas cooling in a closed circuit. Pumped by a turbo for example (or rather a mechanical compressor since the cooling of the collector already pumps the energy of the gases)


PS: I looked with the spreadsheet that I had made last year for a work on the Stirling: finally we can arrive at a return of 0,30 with 400 ° C / 20 ° C (fluctuating from a few % depending on the geometric parameters of the motor)

[Petrus]

The electric / stirling hibrid car already exists.
Based on a think with a stirling in the trunk:
http://memebox.com/futureblogger/show/1247
http://www.hybridcarblog.com/2008/11/de ... ybrid.html

[fthanron]

Right here : http://www.deformat.org/post/2007/08/09 ... Dean-Kamen you can see the same thing in French and as a bonus an electro-stirling scooter?

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[chatelot16]

the stirling is interesting in cases where other thermal machines are not suitable

to burn fuel the petrol or diesel piston engine is the best

to recover the heat lost from this engine the best is the steam engine: far better than stirling

the engine block can be used as a boiler; an engine running very well cooled to around 100 ° C, the exhaust pipe can also be used as a boiler

remains to add steam turbine and condenser: it will be too heavy for a car, but it would be very good for a boat or a locomotive

Besides, it already exists for very large boat engines, it saves 5% on the total yield, which exceeds 50%

[Olivier22]

to burn fuel the petrol or diesel piston engine is the best

More flexible, but not better: thermal Stirlings easily have a 40% efficiency; no distribution system, less friction; continuous combustion is easier to control than rapid combustion in the cylinders; combustion under atmospheric pressure = no NOx emission.

[vertderage]

A hybrid stirling / elec it seems not bad in theory: fairly clean combustion, interchangeable fuel, the lack of flexibility no bp: constant or almost constant speed, it is to be quantified.