Yup, phase changing. Water in vacuum has to touch the heat source, evaporate, travel to the cooler side, condense and start over. As soon as your heat source prevents the cooling from happening, the cycle stops and it over heats. Like there’s a point at which the water can’t cool the source because its overwhelming.
What do you think heat pipes contain? Basically the same thing as water cooling systems.
Water cooling is basically a misnomer - it’s basically a heat relocation system that that gets the heat moved to what are usually air coolers that pass the heat off into the air. If the airflow in your PC is ideal and smart enough, no need for water cooling, you can air cool at the source at nearly the same efficiency, no need for a pump. It’s not as easy to manage in terms of space, but it has less maintenance issues.
I mean to say that a heat pipe not only contains less water per unit area for the phase changing cycle, since its under vacuum, but also the cycle only works at a particular heat per unit volume and temperature range. If you go past the temp range you get runaway.
Water in an active cycle has an almost unlimited ability to relocate heat. You still need to give that heat to something else, but you can pass a kilo of water thru a tiny labyrinth of fins at the heat source and a large surface area radiator with fan on the heat sink side. Vs a few ounces of water trapped inside a pipe running as a heat engine basically. Active pumping is brute force. At some point you won’t be able to contain the water pressure if your source is too hot, but there are many different working fluids.
Its irritating when we try designing a new cooling system at work and some guy will always want a heat pipe when clearly there is only a narrow band where those things are effective. Specially annoying if you don’t have control over the heat source. If you did have control over the source, then maybe you can tune it for a heat pipe. Car engines don’t have heat pipes. Solar collectors don’t use heat pipes either for the most part. Heat pipes need a constant source of heat that always stays below their max bandwidth.
It doesn’t work for a lot of things, but your PC is basically a couple of flat panels where a lot of heat produced is localized to the GPU and CPU and it is potentially very easy to maintain a directed airflow close to them. A heatsink is basically good enough for that, and almost every GPU incorporates one, even the 5090’s, even though the airflow design usually sucks for all of them because of how generic it is. Speaking of car engines, you can go a step better and precisely control the airflow to get great cooling results just with air cooling: https://www.youtube.com/watch?v=cehXZftIYok
I see your point, but if it works nearly as well, why go for a costlier solution that requires more maintenance and lasts less when it doesn’t require it?
I feel the need to point out that water cooling has an upper limit as well. If you get things hot enough, the water is going to flash into steam, at which point it’s going to decimate whatever system it’s in.
You can add additives to prevent that, but at some point it’s no longer “water”.
Reading this back, I suppose this is pedantism. But still.
Yeah, you control the flashpoint via pressure. the higher the pressure, the higher the temperature. However at some point it makes more sense to use a molten salt, an oil or a liquid metal to transport heat away.
If the temperature is near 20C to 100C there’s nothing like flowing water.
Water moving is much better at removing heat than heat pipes could ever imagine. It depends on how fast the mass of water is moving.
I’m pretty sure the way heat pipes move heat is with water funny enough
Phase changing water
Yup, phase changing. Water in vacuum has to touch the heat source, evaporate, travel to the cooler side, condense and start over. As soon as your heat source prevents the cooling from happening, the cycle stops and it over heats. Like there’s a point at which the water can’t cool the source because its overwhelming.
What do you think heat pipes contain? Basically the same thing as water cooling systems.
Water cooling is basically a misnomer - it’s basically a heat relocation system that that gets the heat moved to what are usually air coolers that pass the heat off into the air. If the airflow in your PC is ideal and smart enough, no need for water cooling, you can air cool at the source at nearly the same efficiency, no need for a pump. It’s not as easy to manage in terms of space, but it has less maintenance issues.
I mean to say that a heat pipe not only contains less water per unit area for the phase changing cycle, since its under vacuum, but also the cycle only works at a particular heat per unit volume and temperature range. If you go past the temp range you get runaway.
Water in an active cycle has an almost unlimited ability to relocate heat. You still need to give that heat to something else, but you can pass a kilo of water thru a tiny labyrinth of fins at the heat source and a large surface area radiator with fan on the heat sink side. Vs a few ounces of water trapped inside a pipe running as a heat engine basically. Active pumping is brute force. At some point you won’t be able to contain the water pressure if your source is too hot, but there are many different working fluids.
Its irritating when we try designing a new cooling system at work and some guy will always want a heat pipe when clearly there is only a narrow band where those things are effective. Specially annoying if you don’t have control over the heat source. If you did have control over the source, then maybe you can tune it for a heat pipe. Car engines don’t have heat pipes. Solar collectors don’t use heat pipes either for the most part. Heat pipes need a constant source of heat that always stays below their max bandwidth.
It doesn’t work for a lot of things, but your PC is basically a couple of flat panels where a lot of heat produced is localized to the GPU and CPU and it is potentially very easy to maintain a directed airflow close to them. A heatsink is basically good enough for that, and almost every GPU incorporates one, even the 5090’s, even though the airflow design usually sucks for all of them because of how generic it is. Speaking of car engines, you can go a step better and precisely control the airflow to get great cooling results just with air cooling: https://www.youtube.com/watch?v=cehXZftIYok
I see your point, but if it works nearly as well, why go for a costlier solution that requires more maintenance and lasts less when it doesn’t require it?
I feel the need to point out that water cooling has an upper limit as well. If you get things hot enough, the water is going to flash into steam, at which point it’s going to decimate whatever system it’s in.
You can add additives to prevent that, but at some point it’s no longer “water”.
Reading this back, I suppose this is pedantism. But still.
Yeah, you control the flashpoint via pressure. the higher the pressure, the higher the temperature. However at some point it makes more sense to use a molten salt, an oil or a liquid metal to transport heat away.
If the temperature is near 20C to 100C there’s nothing like flowing water.