24V vs 12V voltage control level

[Serious Hare]

Hi, I want to replace a 24V fan in a (not pc) power supply with a 12V fan to drop it's noise level. I Already got a DC-DC converter. But when measuring the voltage going to the stock fan it only gives 14.5V. Now I know this isn't anything bad, just the fan not running at full speed.

My question is, assuming both fans would have the same speed/pressure at there max voltage, if I can just take half of the 14.5V going to the current fan to get similar speed/pressure on the 12V fan.



 

[kkpatel87]

8 minutes ago, Serious Hare said:

Hi, I want to replace a 24V fan in a (not pc) power supply with a 12V fan to drop it's noise level. I Already got a DC-DC converter. But when measuring the voltage going to the stock fan it only gives 14.5V. Now I know this isn't anything bad, just the fan not running at full speed.

My question is, assuming both fans would have the same speed/pressure at there max voltage, if I can just take half of the 14.5V going to the current fan to get similar speed/pressure on the 12V fan.

So its not quite that simple.

 

If you want to quiet down the 24V fan, the simplest solution would be to put a resistor in the input line to create a low noise adapter.

[Serious Hare]

I don't want to quiet down the 24v fan, I want to replace it with a Noctua fan. The currently installed fan is a Panaflow industrial fan. When I put the Noctua al full speed next to the 24v fan at 14.5V load the Noctua is already quieter than the Panaflow, so already a win. And looking at the spec sheets the Panaflow at full speed has only a little more Airflow/CFM that the Noctua.

I was just wondering how far I could drop the voltage on the Noctua, to get closer to what the Panaflow would output at the used 14.5V