混合工質(zhì)變濃度熱泵系統(tǒng)的研究

1、2007 ASHRAE Annual MeetingConserving Natural Resource Use in Buildings William Tschudi Tengfang Xu Lawrence Berkeley National LaboratoryASHRAE Annual MeetingLong Beach, California Fan-Filter Testing - The Results Are InOverviewnBackground leading to t

2、esting fan-filter unitsnDescription of test configurationnIllustrative resultsnUse of the procedurenPossible next stepsBackgroundnPrevious cleanroom benchmarking illustrated a large variation in air recirculation efficiencynSystems with fan-filter units typically were found to be less efficientBench

3、marked Recirculation System EfficienciesBackground, contIn 2000, a Taiwanese Research Institute evaluated fan-filter units a wide range of performance was notedBackground, contWe then began developing a standard test procedure for fan-filter units to help get “apples-to-apples” comparisonsThe proced

4、ure is now available on our website. It was used in the evaluation of 17 2x4 fan-filter units to “test” the procedure and obtain performance informationTest ConfigurationLayout in test lab MD4FHumidityBoosterFanDamperTemperaturePower meterRPM meterPressureSensorFan-filter UnitAirflowStraightenerAirf

5、lowNozzleConfiguration was dictated by space availableFlow meter An Accurate, Calibrated Flow Nozzle Determined Air Flow Flow measurement: Pressure Tap (Pitot Tube) Pressures were determined at various places throughout the systemElectric Power Monitoring Equip.Available From Utility Tool Lending Li

6、braryTesting Considerations nAir flow rate measurementsnPressure measurementsnPowernDevice calibration and uncertaintiesnIntegrity of the testing system, e.g. leakage nSize of testing rignAdditional parameters, e.g., space/material costnAmbient conditions Sample Operating conditionsUnit with AC moto

7、r tested within its operating range Operating conditions, cont.Unit with ECM motor tested within its operating range Total electric power demand of the fan filter unit under selected operable conditions: 20 Pa Dp 150 Pa, Q 9.9 m3/min (or 0.08 iwc Dp 0.6 iwc, Q 350 scfm) Total Electric Power Demand (

8、W)Pressure (Pa)20406080100120140Airflow Rate (scfm)400500600700800160 170 180 Airflow cfmTotal Pressure EfficiencynFor FFUs with a multi-speed-drive, the total electric power demand may be calculated as:nDp is the pressure differential across the fan filter unit nQ is the airflow rate across the uni

9、t under standard atmospheric condition.nCi,j (i, j = 0, 1, 2) is a coefficient developed from experimental data through polynomial regressions.FFU power efficiencyFFU power efficiency (Et) is defined as the airflow dynamic power divided by the total electric power input to the FFU unit. The FFU powe

10、r efficiency includes electrical and mechanical efficiency of the FFU unit taking into account fan motors, fan design, housing, etc.Et = Pt Q / W Pt = FFU pressure rise (Pa)Q = air flow rate (m3/s)W = electric power input to FFU (W) FFU Total Pressure EfficiencyTotal pressure efficiency of the fan f

11、ilter unit under selected operable conditions: 20 Pa Dp 150 Pa, Q 9.9 m3/min (or 0.08 iwc Dp 0.6 iwc, Q 350 scfm) Total Pressure Efficiency Pressure (Pa)20406080100120Airflow Rate (scfm)3504004505005506000.05 0.10 0.15 0.20 Airflow cfmTotal pressure efficiency of the fan filter unit under selected o

12、perable conditions: 20 Pa Dp 150 Pa, Q 9.9 m3/min (or 0.08 iwc Dp 0.6 iwc, Q 350 scfm) Total Pressure Efficiency Pressure (Pa)20406080100120140Airflow Rate (scfm)4005006007008000.00 0.05 0.10 0.15 0.20 Airflow cfmEfficiency ComparisonsnVariations in electric power and efficiencynMore than a factor o

13、f 10 difference for the same unit across different operating conditionsnDifferent units varied by 3 to 4 times for the same operating conditionnVariation patterns not obvious Efficiency in the Range of Interest Variation of FFU EfficiencyTotal Pressure Efficiency0%5%10%15%20%25%30%0%10%20%30%40%50%6

14、0%70%80%90%100%Percentile Ranking: A higher percentile corresponds to higher total pressure efficiency Xu, T. 2006 (9). Cleanrooms Magazine. Standard Development and Laboratory Testing of Fan Filter UnitsEfficiency ComparisonsnECM motors tended to be more efficient however overall unit design influe

15、nces efficiencynSimple metrics not sufficient depends upon pressure and flow How to Identify Efficient FFUsnImplement Standard Lab Testing nStandard test protocols to fully characterize performancenStandard reporting nDetermine expected range of operating conditionsnReview test results in range of e

16、xpected operationnSelect unit considering energy performance along with other desired featuresIncentive Criteria DevelopmentnRelative performance ranking systemnquantify the observed differencenidentify rebate-criteria. nRelative ranking scores nexamine the robustness of the suggested initial rebate

17、 criteria. nOnce an incentive criteria is set, units that exceed that threshold can be selectedRecommended PracticeIEST RP CC036.1 Testing Fan Filter UnitsnWorking draft of RP036.1 is being developednInterested parties are encouraged to participateRecommendationsOwners/designers - define requirement

18、s for nAir recirculation nAir change ratenAir flow ratenCleanlinessnUniform air flownSystem designnPressure conditionsRecommendations Procurement of fan-filter unitsnDefine range of operating conditionsnRequire testing in accordance with standard test procedurenEvaluate performance in the range of interestnSelect based upon efficiency or perform life cycle cost analysisUse of the standard test procedurenA major semiconductor manufacturer adopted standard, built a test rig, and required bidders to provide units for testing as part of the procurement processnAn Asian company re