[8-Ball]

Winewood,

I have to agree with Brian here.

While it is your opinion that peltier cooling a graphics card may appear to be a waste of money, the original poster has already decided that he will try it anyway.

He was asking a question about the mode of operation of this TEC/waterblock, which you chose not to comment on, instead voicing your opinion on a matter not originally questioned.

As for your comments about the "quality of the forum", it is brought down by people like yourself. If you want to throw your opinions about, particularly if it does not provide answers to the question at hand, then perhaps you should have a look at OCforums.

I'm sure there are threads around here somewhere discussing the benefits of peltier cooling a gpu. THIS thread is asking whether a hot plate is needed between the peltier and the coolant.

If you have no useful experience or knowledge to impart, or find a constructive way to contribute to the thread then don't post.

[/rant]

[back on topic]

There are a number of questions that need asking.

1. What is the heat load from the hot side?

2. What is the convective heat transfer coefficient for the flat surface of the block?

3. Would adding a copper hot plate with furniture of some kind, whther this be designed to increase turbulence or surface area, or both, provide a sufficient increase in convective heat transfer coefficient at the interface with the coolant and the hot plate, to more than compensate for the additional temperature gradient required across the copper heat plate to transfer the heat. The thickness of the copper plate will play a large part here.

4. Clamping pressure. Is it the case that clamping pressure is required to reduce the thermal resistance of the interfaces between TEC and copper, or does it also affect the performance of the TEC itself, by compressing the peltier. If this is the case, then having the hot side cooled directly might reduce the efficiency of the TEC directly by reducing the pressure on the TEC.



I suspect that if you use a more powerful TEC, then it may become necessary to use a hot plate with an intricate furniture to provide the highest possible convective heat transfer coefficient, however, for a low power TEC, such as that provided as standard with the MCW50T, will be sufficiently cooled by direct contact with the coolant.

I would also suspect that in this case, the performance would be LARGELY dependent on the flow rate, whereby if the flow rate were too low, the convective heat transfer coefficient would be too low, requiring a large temperature delta between the coolant and the TEC hotside but since the geometry factor of the convection is poor, then turbulence will have to be introduced by means of high flow rates.

As for whether the clamping pressure affects the TEC directly as opposed to just affecting the thermal interfaces, I don't know the answer to this, but I suspect there will be someone here who does.

8-ball