WPC e}Yi ,r&0lQX9|/q 0ci(BWF0 WZxEC-ڸeٿc-XJ90~EF"!"b(u;rIߨ1̢GB?51PM1;8C21Ov-иj!qu甾qr]-Tw}h> P:QzB1Ȳk@SAA9|/N#ג/,qO9l0qٮGMb!g Ov/ -ވ}7 \w^p<ōY??a,~ʾ9ӏvCtλIw֦E$OBֻP(q|*2UP %LR 0C EI U:K  nX B  0( 2 UPU:lw4=> y`$8Lucida Sans TypewriterTT'     0 .  d SUMMARY ; A C p value of 0.84 can be used when stack velocities are as low as 7 ft/sec provided Type S pitot tubes that meet the design specifications described in Method 2 are used. DISCUSSION ; It is well accepted that properly constructed potot tubes do not need to be calibrated (reference 1).  K)  X? '!dE!?X'XXXXX'Preparedby RoyH.Huntley ,EMB   D     EMCGD006 t  TechnicalSupportDivision,OAQPS,EPA D     January20,1995 T ? ',!dE,!?(2K$  !  <6X9`("Courier NewTT#|d=> y`$8Lucida Sans TypewriterTTd>@XhQ@<6X9`("Courier NewTTriterTTXXx6X@DQX@ d($  K)  X? '!dE!?X'XXXXX'Preparedby RoyH.Huntley ,EMB   D     EMTICGD006 t  TechnicalSupportDivision,OAQPS,EPA D     January20,1995 T ? ',!dE,!?=> y`$8Lucida Sans TypewriterTT<6X9`("Courier NewTT{$<  !    , XQ=X@` hp x (#%'XQ? '$!dE$!?X'XXXXX'@..' EMISSIONMEASUREMENTTECHNICALINFORMATIONCENTER  @JJ+GUIDELINEDOCUMENT  d ? ',$!dE,$!?@RR COEFFICIENTSOFTYPESPITOTTUBESATLOWFLOWRATES <  SUMMARY  t  ACpvalueof0.84canbeassignedtoproperlyconstructedType-Spitot ( x  tubesthroughoutthevelocityrangenormallyencounteredinstacktesting,includingvelocitiesthatcorrespondtothelowerlimitofamanometer'sreadability. DISCUSSION  ,|  AccordingtoOwerandPankhurst1,errorsforvelocitymeasurementwitha 0 standardpitottubearelessthan0.5percentforflowratesbetween3and200ft/sec.InastudyinvestigatingtheuseofType-Spitottubesforthemeasurementoflowflowrates,Vollaro2calibratedtwelveTypeSpitottubesagainst T astandardpitotatvelocitiesrangingfrom6.7ft/sec,whichistypicallyveryclosetothelowerlimitofthereadabilityofaMethod5manometer,to17ft/sec.Eachofthepitottubeshadbeenpreviouslycalibratedathighervelocities,rangingfrom25to58ft/sec,providing"reference"Cp's T foreachpitottube.Ingeneral,theCp'svariedlittlefromthe (x "reference"Cp's.Theaveragedifferencewas2.1percentwithanaverage L deviationof1.3percent. REFERENCES  L ! 1.0 @ Ower,E.andR.C.Pankhurst.TheMeasurementofAirFlow.London, "P# PergamonPress,1966.p.35. @%@% 2.0 @ Vollaro,R.F.TheUseofTypeSPitotTubesfortheMeasurementof |$& LowVelocities.EmissionMeasurementLaboratory,U.S.EnvironmentalProtectionAgency,ResearchTrianglePark,NC. @%@%  ,(0 Ї