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[VXL V6]

some may not have the mix right, or checked it.??

How does that work then? Antifreeze / Coolant is basically an additive that makes water impure hence lowering the freezing point and raising the boiling point of the water, there are other products added to the coolant such as RUST inhibitors but to the best of my knowledge none of this would effect when a thermostat opens or closes.

[CaptainZok]

some may not have the mix right, or checked it.??

How does that work then? Antifreeze / Coolant is basically an additive that makes water impure hence lowering the freezing point and raising the boiling point of the water, there are other products added to the coolant such as RUST inhibitors but to the best of my knowledge none of this would effect when a thermostat opens or closes.

 

[Debs.]

some may not have the mix right, or checked it.??

How does that work then? Antifreeze / Coolant is basically an additive that makes water impure hence lowering the freezing point and raising the boiling point of the water, there are other products added to the coolant such as RUST inhibitors but to the best of my knowledge none of this would effect when a thermostat opens or closes.

 

Ethylene glycol disrupts hydrogen bonding when dissolved in water.
Pure ethylene glycol freezes at about -12°C (10.4°F), but when mixed with water molecules, neither can readily form a solid crystal structure, and therefore the freezing point of the mixture is depressed significantly.
The minimum freezing point is observed when the ethylene glycol percent in water is about 70%.
This is the reason pure ethylene glycol is not used as an antifreeze--water is a necessary component as well.

As Ethylene Glycol is considerably more dense than plain-water....might fluid dynamics come into play with sticky thermostats in cold temps. :-?

[VXL V6]

Does the 50% ethylene glycol / water solution absorb heat from the block at a different rate to lower %age concentrations?

[Debs.]

Does the 50% ethylene glycol / water solution absorb heat from the block at a different rate to lower %age concentrations?

Pure ethylene glycol has a specific heat capacity about one half that of water. So, while providing freeze protection and an increased boiling point, ethylene glycol lowers the specific heat capacity of water mixtures relative to pure water. A 50/50 mix by mass has a specific heat capacity of about 0.75 BTU/lb F, thus requiring increased flow rates in same system comparisons with water. Additionally, the increase in boiling point over pure water inhibits nucleate boiling on heat transfer surfaces thus reducing heat transfer efficiency in some cases, such as gasoline engine cylinder walls. Therefore, pure ethylene glycol should not be used as an engine coolant in most cases.
So yes, there`s an efficiency curve of specific heat-transfer potentiality versus peak freeze-limitation......50% glycol for the former and 70% glycol for the latter.
As with most things in life, it`s a trade off of various factors: heat transfer, boil prevention and lowering the freeze point.

[hotel21]

The original post was...

Is my Vauxhall dealer extracting the pish. I bought a thermostat and pipe from them before Christmas but haven't used them now they are saying they can't take them back becuase its over 14 days ago

And Freecalls reply was....

some may not have the mix right, or checked it.??

The old school game of Chinese whispers, or am I missing something???  No wonder the thread reads like the cushion of a pinball machine....       

[VXL V6]

Does the 50% ethylene glycol / water solution absorb heat from the block at a different rate to lower %age concentrations?

Pure ethylene glycol has a specific heat capacity about one half that of water. So, while providing freeze protection and an increased boiling point, ethylene glycol lowers the specific heat capacity of water mixtures relative to pure water. A 50/50 mix by mass has a specific heat capacity of about 0.75 BTU/lb F, thus requiring increased flow rates in same system comparisons with water. Additionally, the increase in boiling point over pure water inhibits nucleate boiling on heat transfer surfaces thus reducing heat transfer efficiency in some cases, such as gasoline engine cylinder walls. Therefore, pure ethylene glycol should not be used as an engine coolant in most cases.
So yes, there`s an efficiency curve of specific heat-transfer potentiality versus peak freeze-limitation......50% glycol for the former and 70% glycol for the latter.
As with most things in life, it`s a trade off of various factors: heat transfer, boil prevention and lowering the freeze point.

Right, so (please excuse my ignorance and lack of intelligence here!) what you are saying then is that there is a trade off between the %age mixture of water/coolant (read coolant as anti-freeze solution) and the specific heat it can transfer from the block surfaces?

Therefore i'm guessing that the only way to improve the heat transfer rate is with a greater flow and colder coolant feed (ie thermostat fully open to allow full feed and return to and from Radiator?).

In effect what i'm getting at is that a car with a higher %age concentration of coolant mix will warm up quicker and hence the thermostat will open earlier....

[Debs.]

Does the 50% ethylene glycol / water solution absorb heat from the block at a different rate to lower %age concentrations?

Pure ethylene glycol has a specific heat capacity about one half that of water. So, while providing freeze protection and an increased boiling point, ethylene glycol lowers the specific heat capacity of water mixtures relative to pure water. A 50/50 mix by mass has a specific heat capacity of about 0.75 BTU/lb F, thus requiring increased flow rates in same system comparisons with water. Additionally, the increase in boiling point over pure water inhibits nucleate boiling on heat transfer surfaces thus reducing heat transfer efficiency in some cases, such as gasoline engine cylinder walls. Therefore, pure ethylene glycol should not be used as an engine coolant in most cases.
So yes, there`s an efficiency curve of specific heat-transfer potentiality versus peak freeze-limitation......50% glycol for the former and 70% glycol for the latter.
As with most things in life, it`s a trade off of various factors: heat transfer, boil prevention and lowering the freeze point.

Right, so (please excuse my ignorance and lack of intelligence here!) what you are saying then is that there is a trade off between the %age mixture of water/coolant (read coolant as anti-freeze solution) and the specific heat it can transfer from the block surfaces?

Therefore i'm guessing that the only way to improve the heat transfer rate is with a greater flow and colder coolant feed (ie thermostat fully open to allow full feed and return to and from Radiator?).

In effect what i'm getting at is that a car with a higher %age concentration of coolant mix will warm up quicker and hence the thermostat will open earlier....

My understanding is that lower glycol percentile concentrations would be more efficient at specific heat transfer, but at the inversely proportionate disadvantage of the greater risk of boiling and with reduced freeze protection......but, the graph curve at greater percentile glycol mixes for heat-transfer versus freezing and boil prevention can be favourably shifted by increased circulation-speed/throughput (the other modifier).

The viscosity specifics of water and glycol 'at various temperatures' also makes for interesting reading:
http://physics.info/viscosity/

[tidla]

Does the 50% ethylene glycol / water solution absorb heat from the block at a different rate to lower %age concentrations?

Pure ethylene glycol has a specific heat capacity about one half that of water. So, while providing freeze protection and an increased boiling point, ethylene glycol lowers the specific heat capacity of water mixtures relative to pure water. A 50/50 mix by mass has a specific heat capacity of about 0.75 BTU/lb F, thus requiring increased flow rates in same system comparisons with water. Additionally, the increase in boiling point over pure water inhibits nucleate boiling on heat transfer surfaces thus reducing heat transfer efficiency in some cases, such as gasoline engine cylinder walls. Therefore, pure ethylene glycol should not be used as an engine coolant in most cases.
So yes, there`s an efficiency curve of specific heat-transfer potentiality versus peak freeze-limitation......50% glycol for the former and 70% glycol for the latter.
As with most things in life, it`s a trade off of various factors: heat transfer, boil prevention and lowering the freeze point.

Right, so (please excuse my ignorance and lack of intelligence here!) what you are saying then is that there is a trade off between the %age mixture of water/coolant (read coolant as anti-freeze solution) and the specific heat it can transfer from the block surfaces?

Therefore i'm guessing that the only way to improve the heat transfer rate is with a greater flow and colder coolant feed (ie thermostat fully open to allow full feed and return to and from Radiator?).

In effect what i'm getting at is that a car with a higher %age concentration of coolant mix will warm up quicker and hence the thermostat will open earlier....

My understanding is that lower glycol percentile concentrations would be more efficient at specific heat transfer, but at the inversely proportionate disadvantage of the greater risk of boiling and with reduced freeze protection......but, the graph curve at greater percentile glycol mixes for heat-transfer versus freezing and boil prevention can be favourably shifted by increased circulation-speed/throughput (the other modifier).

The viscosity specifics of water and glycol 'at various temperatures' also makes for interesting reading:
http://physics.info/viscosity/

i agree!?!

[VXL V6]

Does the 50% ethylene glycol / water solution absorb heat from the block at a different rate to lower %age concentrations?

Pure ethylene glycol has a specific heat capacity about one half that of water. So, while providing freeze protection and an increased boiling point, ethylene glycol lowers the specific heat capacity of water mixtures relative to pure water. A 50/50 mix by mass has a specific heat capacity of about 0.75 BTU/lb F, thus requiring increased flow rates in same system comparisons with water. Additionally, the increase in boiling point over pure water inhibits nucleate boiling on heat transfer surfaces thus reducing heat transfer efficiency in some cases, such as gasoline engine cylinder walls. Therefore, pure ethylene glycol should not be used as an engine coolant in most cases.
So yes, there`s an efficiency curve of specific heat-transfer potentiality versus peak freeze-limitation......50% glycol for the former and 70% glycol for the latter.
As with most things in life, it`s a trade off of various factors: heat transfer, boil prevention and lowering the freeze point.

Right, so (please excuse my ignorance and lack of intelligence here!) what you are saying then is that there is a trade off between the %age mixture of water/coolant (read coolant as anti-freeze solution) and the specific heat it can transfer from the block surfaces?

Therefore i'm guessing that the only way to improve the heat transfer rate is with a greater flow and colder coolant feed (ie thermostat fully open to allow full feed and return to and from Radiator?).

In effect what i'm getting at is that a car with a higher %age concentration of coolant mix will warm up quicker and hence the thermostat will open earlier....

My understanding is that lower glycol percentile concentrations would be more efficient at specific heat transfer, but at the inversely proportionate disadvantage of the greater risk of boiling and with reduced freeze protection......but, the graph curve at greater percentile glycol mixes for heat-transfer versus freezing and boil prevention can be favourably shifted by increased circulation-speed/throughput (the other modifier).

The viscosity specifics of water and glycol 'at various temperatures' also makes for interesting reading:
http://physics.info/viscosity/

Sorry yes I see what your saying. I think my angle was that the block would heat up quicker because the coolant couldn't dissasipate the heat quickly enough, where my angle went a full 360 degrees and failed was that I failed to take into account that because the coolant mixture was less able to dissasipate the heat the thermostat would take longer to open as it relates directly to the coolant temperature.... which is lower....

So I guess the answer would be a thermostat that opens at a lower temperature... Ultimately though I would imagine the Coolant mix %age is probably calculated on the working limits the manufacturer specifies for the car.

[Dishevelled Den]

Interesting questions from V6 and great replies from Deb. 8-)