It arrived quietly, but we had been looking forward to it for a very long time. In its form factor, the Phanteks T30-140 fan works wonders and often defeats everything that stands in its way. Yes, even the Noctua NF-A14x25 G2 PWM is often the “next in line”, albeit at the cost of a thicker profile (and therefore worse compatibility). Airflow is exceptionally high (and consequently cooling performance) through obstacles. Larger fans now have a new dominant model.
… and of airflow
With airflow measurements, we can well explain why the test tunnel is shaped the way it is. It doesn’t consist of two parts just so that the “exhaust” can be conveniently clogged for pressure measurements. The anemometer (i.e. the wind speed measuring instrument) is held together by two parts, two formations, through the flanges.
The front part, at the beginning of which the fan is mounted, becomes steadily narrower and from about two thirds of the way through the cross-section is smaller than that of a 120 mm fan. The reason for this is that the cross-section of the anemometer is always smaller than that of the fans tested. The taper towards the anemometer fan is as smooth as could be chosen and the tunnel walls are smooth. This has minimized the occurrence of unnatural turbulence.
The difference between the cross section at the intake (fan under test) and at the constriction point (anemometer) also means a difference in dynamic pressure, the principles of the Venturi effect apply here. In order to avoid distortion at this level and to ensure that the fan airflow is not different from what it actually is, the Bernoulli equation must be applied to the measured values (for maximum accuracy, the calculation also takes into account the internal cross-sectional area of the anemometer, i.e. its inactive part ). After all this, it is again possible to confront our results with the paper parameters.
We use an Extech AN300 anemometer with a large 100 mm fan for the measurements. Its big advantage over other anemometers is that it is made for bidirectional sensing. This allows tests at different fan orientations. However, the “pull” position is more suitable or accurate for measurements, even though it may not seem so at first glance, but we’ll explain.
Here, we get to the second part of the tunnel, the part behind the anemometer. It is part of the whole device, mainly to allow a laminar flow of air to arrive at the impeller of the anemometer. Otherwise, uncontrolled side whirls would be reflected in the results, which are inconsistent with accurate measurements. Therefore, we will test the flow in the pull position. If anyone would like us to elaborate more on this topic, we can elaborate further at any time in the discussion below the article. Ask away. 🙂
In regard to the anemometer, we shall return for a bit to noise measurements and to setting modes according to fixed noise levels. It may have occurred to you as you were reading that the anemometer fan is also a source of sound that needs to be filtered out when measuring fans. For this reason, we insert a securing pad between the frame and the anemometer fan before each measurement and mode setting according to the fixed noise level. This, by the way, also holds the anemometer fan during static pressure measurements.
One photograph labeled “v2” is intended for the main teaser:
Can you help me understand the importance of “Static pressure through a through a thicker radiator” when we also have “Airflow through a thicker radiator”? It seems to me that the airflow is the end result and static pressure is just one variable that leads to that resulting airflow. You get a fan like the Endorfy Fluctus 140 that rates high on static pressure at 31dB but then underperforms on airflow at the same dB against other fans that had lower rated static pressure.
Static pressure through a radiator represents a scenario where the measured value reflects the combined effect of the fan and the radiator. In contrast, the results labeled Static pressure w/o obstacles are influenced solely by the fan itself.
Typically, a radiator (or any obstacle) reduces static pressure. If the obstacle does not provide sufficient resistance, pressure leakage occurs, and we measure lower values as a result.
From a practical perspective, however, these values are not critically important. It’s important to understand the conditions under which static pressure is measured — regardless of whether an obstacle is present or not. The measurement is performed at zero airflow, with the tunnel sealed.
When measuring Airflow through a radiator, the situation is essentially the opposite. Speaking of “zero static pressure” would be somewhat inaccurate (since even the tunnel itself introduces a small amount of resistance), but this resistance is very low. In that case, airflow restriction is determined primarily by the obstacle itself.
Static pressure measured through a radiator may correlate better than airflow values in extremely restrictive environments—but such conditions do not represent typical real-world scenarios.
Is the answer clear enough and satisfactory or is there something that needs to be further clarified? 🙂
This helps very much. Thank you for taking the time to explain it so clearly for me.
What a waste of a fan
What facts are you basing that on? In certain situations, when things are set up properly, the Phanteks fan can actually be number one. 🙂
Could you explain why 120mm G2 Noctua beats T30-120, but T30-140 beats Noctua 140mm G2? Is Noctua 140mm G2 for some reason worse than 120mm version? For example at 31dBA 140mm Noctua on thick/thin radiators has less airflow than 120mm version
Could you please provide specific situations or measurements? I’m not able to work with the term “beats” on its own—it’s too vague. What exactly do you mean by that? Please elaborate in more detail so it’s clear what needs to be explained. 🙂
Hello – I am not skilled in Electronics. I ordered the 3x pack of this Phanteks T30-140, can I run them – all three of them – off of one 3A “PUMP_SYS2” header on my motherboard?
Hi, connecting the Phanteks T30-140 fans should be fine even at maximum speed—assuming the connector is designed to handle higher current loads. These fans don’t come close to 3 A even at peak draw during startup, etc. 🙂