Heat storage system (Prius-like insulated coolant reservoir)

[Josh8loop]

Originally Posted by Demolite

After a long time I'd like to share some things i noticed with my system. I recommend you don't use straight coolant to coolant transfer, the expansion system is very hard to do and the pressure of the cooling system doesn't stay in normal limits. Core plugs started to leak and the Uno's head gasget blew, propably as a result of coolant leakage. I suggest using insulated tubing to transfer heat and a pump in the system makes controlling and transferring heat quicker.

Did you mainly have issues since you effectively increased coolant system volume without providing adequate expansion volume? I have recently been reading about this on CAT engines. They mention the coolant volume vs. air expansion space needed to provide shutoff after boil protection. I am actively working on my thermal storage setup that is Dewar based and want to make sure I learn from your mistakes.

[Demolite]

Yes and no.

Your radiator cap should keep pressure in the system at a safe level. No matter how much coolant you have. However on the Uno the built in "radiator+expansion tank" -systems "overflow cap" venting holes are very small so maybe they couldn't put out the coolant fast enough. This is all speculation on what really happened, maybe it was just old age.

The reservoir was in the trunk and the system capacity was about 25 liters at one point. When it all got hot, expansion was about 1.5 liters, in a system designed for less than 0.5. A fully functioning system will spill this out into the expansion tank, the Uno however spilled it from the weakest spots. Lowering overall pressure and causing boiling.


So in other words, if your car's cooling system is good and can hold a little higher pressure and your radiator cap works, you're should be fine. You will need a bigger expansion tank though.

[Obormot]

hello!

such system already was in serial production in Russia many years ago, name "U.O.P.D." (= УОПД in russian).
designed for improving of starting cold engine in extremally low temperatures, like -30...-40C and lower.

but production was stopped in 2010, i don't know why, becouse idea was good, and was demand for it.









now you can fing another system, "Golfstream".





heat accumulator can be easily removed.
for example, for storing at home in warm.
or for quick refilling by hot antifreese at home.

http://golfstream-nsk.ru/products

[Piwoslaw]

I wonder if Toyota knows that they were not first?

[Demolite]

The operation looks to be almost automatic, based on the pictures. The reservoir is probably non-pressurised, and only fills with hot overflowing water from the radiator. Then its pumped back, when needed. Only one pump, no worry of extra pressure. Nice idea.

[Pandaf]

Subscribed. My car has pretty much the same engine. I have a block heater but no possibility of using that on the way home from work, so I need to look into the possibilities mentioned in this highly interesting thread.

[Obormot]

translated system description

[euromodder]

Something I've been pondering about ...

Make some quick-disconnect fittings on the hot and cold coolant lines.
Connect, and run the other end though a heat exchanger that plugs into the central heating / warm water supply system. A very low power pump could circulate the coolant.

Kind of similar to how solar boilers fit into the heating/warm water system, but with the option to disconnect it easily.

[NoD~]

Necrobump!

I'm looking into something like this for my Neon. Most of my drives are under 4 miles and between 8-16 hours between drives. Obviously, my engine is back to ambient temps by then, so I'm thinking something like this may be a good way to go.

I have room in my engine bay (since I use a smaller radiator and smaller battery) and found a stainless steel canister that should do the trick.

I'm thinking of getting a Saab coolant bypass (a Y type) that would tap into the heater line. Shortly after, tap in with a T for the return. This would make it pull from the engine and push into the heatercore. Use a cheap and simple 12v vacuum pump to open the bypass valve from a switch and a basic 12v water pump off the same circuit to pump the coolant through. Use perhaps Styrofoam for tank insulation? This would have to all be done manually with a push of a button, but I'd trust that more anyways (and would be far easier and cheaper than trying to put something automatic together).

Any thoughts on something like this?

[Daox]

The 2nd gen Prius engineers thought it was a worth while mod. I agree for short trips, anything you can do to speed up warm up is good. I have a 7 mile commute and warm up mods are just about #1 for me after maintenance.