I stand corrected as slightly different search terms found a few. However, they are all for Sunon fans (Sunon being Japanese). The first two links:
http://octopart.com/gm0504pev2-8.gn-sunon+fans-82640 http://cpc.farnell.com/1/1/9926-dc-axial-flow-fan-40x40x20-kde1204pkv2-ms-gn-sunon.html They include data in L/s and m³/h in addition to CFM. The first link has a link to a pdf catalog at the top of the page. On the detail pages for each fan, there is a graph of flow vs static pressure. The units are (only) cfm, and water column, inches H2O, for pressure. I suspect these may be the native measurement units they use, but there is no way to be sure. --- On Fri, 3/18/11, John M. Steele <[email protected]> wrote: From: John M. Steele <[email protected]> Subject: Re: [USMA:50087] Re: PC Case fans & flow measurements To: "U.S. Metric Association" <[email protected]> Date: Friday, March 18, 2011, 9:03 AM I attempted a Google search, but it didn't turn up any foreign ads or articles. The dimensions are all in millimeters. I'm sure there is a metric rating but I don't know what it is. So the best approach I can identify is to try the usual suspects. A flow in CFM to five significant figures is obviously absurd. Maybe some located in a metric country can find some local specs. --- On Fri, 3/18/11, Remek Kocz <[email protected]> wrote: From: Remek Kocz <[email protected]> Subject: [USMA:50087] Re: PC Case fans & flow measurements To: "U.S. Metric Association" <[email protected]> Date: Friday, March 18, 2011, 8:36 AM Guys, thanks for the conversion factors, but that's not what I was asking for. My question is specifically about metric units of airflow for PC fans. Is there an accepted, standardized metric unit reported for airflow in PC fans, like CFM is in the imperial? Remek On Fri, Mar 18, 2011 at 6:32 AM, John M. Steele <[email protected]> wrote: Try out each conversion, and see which leads to round numbers. To expand on Jim's factor: 1 ft3/min = 0.471 947 4 L/s = 28.316 84 L/min = 1.699 011 m³/h --- On Fri, 3/18/11, Remek Kocz <[email protected]> wrote: From: Remek Kocz <[email protected]> Subject: [USMA:50081] Re: PC Case fans & flow measurements To: "U.S. Metric Association" <[email protected]> Date: Friday, March 18, 2011, 12:13 AM Because I'm not sure what's used in the metric world of airflow measurement. I recall seeing maybe cubic meters per hour, but I know for sure that it wasn't L/min. On Thu, Mar 17, 2011 at 5:25 PM, James R. Frysinger <[email protected]> wrote: Why don't you calculate how may liters per second those figures come out to? Or liters per minute? Use 1 ft3/min = 0.471 947 4 L/s according to SP 811. Jim On 2011-03-17 1550, Remek Kocz wrote: I'm shopping around for a PC case fan, and I noticed a strange trend in terms of airflow measurements. Whereas in the past it used to be that the cubic foot per minute numbers were fairly round and elegant, these days they've become strange, with up to two figures past the decimal point. I can assume that the Asian manufacturers began insisting on the metric terms, and these oddball CFM's are the conversions. Any ideas? -- James R. Frysinger 632 Stony Point Mountain Road Doyle, TN 38559-3030 (C) 931.212.0267 (H) 931.657.3107 (F) 931.657.3108
