High static pressure fans

[trouble]

Dakle,malo sam kontao koji ladnjak uzet za moj cooler,i googlajući došao sam do svega par tekstova koji objašnjavaju da za ventove za proc,koji se susreću s gustim meshom metala(čitaj: otpora) ne vrijedi pravilo više rpm-a i cfm-a = bolje. Kod njih se gleda jedna mjera koji proizvođači često uskračuju javnosti: statički pritisak/static pressure ili na dojče: Luftdruck(jedinica je mm-H2O).

Ukratko,većina fanova s niskim statičkim pritiskom(a visokim ostalim vrijednostima) se koriste kao case fanovi,zbog toga jer se susreću s malim otporom kod upuha i ispuha....dok za CPU coolere pogoduje manja skupina ventova s visokim statičkim pritiskom.

Evo i jednog zgodnog teksta s T-Hardwera:

Every fan has a performance curve which describes it's flow and pressure characteristics. The higher the pressure across the fan, the lower the flow through the fan and vice-versa. The pressure across the fan, and hence the flow through the fan, is dictated by the system in which the fan is installed. Things that impede airflow, such as small holes, heatsinks, filters, wires, convoluted flow paths, etc. cause an increase in the pressure required to drive a particular flow. The effect of this is that the more resistance you put in the path of the fan, the more the flow through the fan will drop.
As for the the static pressure quoted by manufactuers- I assume this is either the max pressure the fan can deliver (ie. when flow = 0), or the pressure at the fan's design point (ie. flow = x cfm at y mm H20- or whatever other units of flow and pressure you want to use).
Of course, manufacturers don't seem to make performance curves available to the public, and trying to work out the airflow resistance of your case or heatsink is nigh on impossible, not to mention a waste of time. What you need to know is that systems in which there is a high resistance to flow (heatsinks being a common example) will require a higher static pressure rating than systems which have a low resistance to flow (typically cases). So if you have a high resistance system, like a CPU heatsink, installing a powerful fan with a high pressure rating will ensure you get a decent airflow flow over the heatsink.

Gledajući po netu nigdje nisam našao tu vrijednost za Alpenfohn hladnjake.... a od potencijanih zamjena kao najjače bih izdvojio ova dva:

Noiseblocker BlackSilent Fan XLP - 120mm PWM

Akasa Apache 120mm PWM-Fan - camou


Zanimljivo je da su ti,ventovi s najaćim statičkim pritiskom često i PWM hladnjaci,osim naravno nekih verzija Scythea,Papsta i sl koje se koriste za OC bencheve.....

Znam da nisam otkril toplu vodu ali o ovome na PCE forumu dosad nije bilo riječi,bar ne dosada(tako search kaže)


Ako itko ima šta pametno za dodat....slobodno nam proširite horizonte....

[Sn4k3]

Zanimljivo stivo u svakom slucaju te logicno kad se malo zamislim
Btw, svidja mi se taj BlackSilent Fan XLP.. Ako ko bude naruciva nesto takvo obavezno pm

[baban]

evo imate ovdje zanimljivog stiva o ventovima

kronoloski

http://www.xtremesystems.org/forums/...d.php?t=170224
http://www.xtremesystems.org/forums/...d.php?t=193647
http://www.xtremesystems.org/forums/...d.php?t=221899
http://www.xtremesystems.org/forums/...d.php?t=223391

[trouble]

Bogami ima se tu kaj za čitat,no to su stari testovi,mene više zanima odnos statički pritisak vs broj okretaja.

2Snake> onda bi bilji izbor bila Akasa,zbog toga jer vrijednosti

Airflow: max. 97,74 m³/h
Luftdruck: max. 2,64 mm-H2O

ostvaruje sa svega 1300 o/min za razliku od Noiseblockera koji za nes veci airflow radi na 2000 okretaja....donoseći i veću buku

[hammer_of_thor]

Bilo je već jednom ili dvaput govora na forumu o statičkom pritisku, no sve u par rečenica, a tema je dobra

Akasa sigurno na 1300 rpma ne gura skoro pa 100 CFMa, to je već malo prevelika i nerealna brojka za tako nizak RPM, a može se slobodno povući paralela RPM ==> CFM ==> mm H2O, naravno što manji rpm to manji CFM i manji pritisak, tako da naravno da sve ovisi jedno o drugomu.

npr, jedna Nanoxia FX2000 deklarirano na 2k RPMa i pritisak od ~2.90 mm H2O (skoro 3), dok pri 1200 RPMa pada na ~1.60 mm H2O

[trouble]

nije 100 CFM vec 57.53 CFM (97.74 m3/h)

mixamo termine

[hammer_of_thor]

Moj bed, nisam skužio da si napisao u tim jedinicama

[trouble]

Sve 5....

http://tech-reviews.co.uk/reviews/ak...mm-apache-fan/

Evo josh jedan review Akase,nije premocan ko Nanoxia i noisblocker ali je zato najtisi od njih(i to zapanjujuce ako su ocitane vrijednosti istinite )

At both high (1300rpm) and low (600rpm) speeds the Akasa Apache Fan really amazed me. At low I could not hear any whir at all from the fan when installed in my case; and at high, there was a tiny bit of noise to be heard – but you had to listen really hard to notice. Akasa says at low the fan produces a remarkable 6.9 dBA and at high a subtle 16.05 dBA. This is a massively low recording, easily the lowest claim I’ve ever heard of in fact, but realistically, I believe Akasa because this fan really is dead silent.

[hammer_of_thor]

Morale bi biti istinite vrijednosti buke, a moram priznati i da se ne čudim toliko, sa obzirom da se ipak vrte na HDB ležajevima

Pogledaj si također Noctue, oduvijek su bile superiorne svima što se tiće odnosa RPM ==> sve ostalo

Možda malo preskupe (ove nove idu i po ~25€ a piece) no mislim da se isplati kad se već jednostavno uzima jedna za samo cooler.

[Doink the Clown]

Meni za par tjedana stiže ova bebica:
http://www.performance-pcs.com/catal...ducts_id=24570
Nigdje ne mogu naći podatak koliki statički pritisak daje vent.

[trouble]