Download Working Group on Fluid Flow

John Wright
NIST Fluid Metrology Group
May 12, 2011
WGFF Meetings
• Last met in October at FLOMEKO in Taiwan
• International Symposium on Fluid Flow
Measurement, June 18 and 19, 2012 Colorado
Springs, USA
• FLOMEKO, September 18 and 19, 2013 Paris, France
Updating Flow CMCs
 RMO TC Flow members are working on updated flow
CMCs
 CIPM MRA-D-04 paragraph N5: CMCs incorporate
“agreed-upon values for the best existing devices.“ (DUT
uncertainties)
 WGFF will use KC transfer standards as “best existing
device”, reviewing proposed DUT uncertainties on
BIPM Discussion Forum.
Proposed DUT Uncertainties on BIPM Discussion Forum
http://www.bipm.org/jforum/forums/list.page
Calibration Service
DUT Uncertainty (k=2)
Units
Comments
K1 Water flow
0.02
%
Based on CCM.ff-K1 report figures 5 to 8 and
figures 19 to 22.
K2 Hydrocarbon liquid flow
0.02
%
Based on CCM.ff-K2 report figures 2 and 4 to
7 showing repeated cals of TS at NEL.
0.2+0.1/u(m/s)
%
Based on APMP.ff-K3 TS reproducibility, see
"Air Speed" worksheet.
K4 Volume graduated vessel
0.0065+0.035/V(dm3)
%
See the worksheet "Volume" for plots of
these volume uncertainty functions.
K4 Volume volumetric flask
0.0046+0.045/V(cm3)
%
K4 Volume pipette
0.0065+0.073/V(cm3)
%
K5 High-pressure gas flow
0.05
%
K6 Low-pressure gas flow
0.05
%
Cryogenic liquid flow
0.02
%
K3 Air speed
Based on CCM.ff-K5b report table 2.
From Wright Flomeko 2007 paper on the
uncertainty of the CCM K6 TS.
2nd Round of KCs for CCM Approval
K2 Hydrocarbon Liquid Flow:
a) VSL (2 coriolis meters, HL & water)
b) NMIJ
K3 Air Speed: LNE-CETIAT and PTB (LDA &
ultrasonic)
K4 Volume
a) CENAM
c) Micropipettes : IPQ (first KC)
K5 High-Pressure Gas Flow: PTB (merge 5a & 5b)
K6b Low-Pressure Gas Flow: SMU (already approved)
First Round Flow KC Schedules
Water
Start-up / idle
Hydr. Liquid
Procurement / Pre-tests
Air Speed
Protocol development
Volume
KC data collection
Draft A
Natural Gas
Draft B
High P Air
CCM approval and KCDB
posting
Low P Air
0
1
2
3
4
5
6
7
8
Years since June 2000
Average completion time was 7 years!
First Round Flow KC Schedules
6%
Start-up / idle
3%
23%
11%
Procurement / Pretests
Protocol development
KC data collection
16%
Draft A
28%
13%
Draft B
CCM approval and
KCDB posting
Start-up / idle + Procurement / Pre-tests = 51 %
Average KC data collection = 16 months (K5a=1 to K2=26)
Average Draft A + Draft B = 17 months (K5b=7 to K3=23)
Other WGFF Topics…
 Guidelines on linkage, via common TS or common




participants
Improving KC reports, shorter, standard format
Low uncertainties of accredited commercial labs, assist
accrediting bodies with uncertainty checklists
COOMET, AFRIMET participation in other RMOs
Definition of air speed primary standard should not
include 1) pitot tube, 2) rotating arm, 3)LDA without
rotating disk