1 / 33

Similarity Studies for Air Data Probes New Standard – AS5562

Similarity Studies for Air Data Probes New Standard – AS5562. Guilherme da Silva ATS4i Aero-Thermal Solutions for Industry gasilva@ats4i.com.br. Coupled Heat and Mass Transfer Effects. SAE AC-9C Aircraft Icing Technology Committee Meeting #57 October 8th-10th 2010 - Portland, OR.

locke
Download Presentation

Similarity Studies for Air Data Probes New Standard – AS5562

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Similarity Studies for Air Data Probes New Standard – AS5562 Guilhermeda Silva ATS4i Aero-Thermal Solutions for Industry gasilva@ats4i.com.br Coupled Heat and Mass Transfer Effects SAE AC-9C Aircraft Icing Technology Committee Meeting #57 October 8th-10th 2010 - Portland, OR

  2. Introduction SAE AIR1168/4 Model Coupled Heat and Mass Transfer Effects of Impingement and Ice Crystals Conclusions and Possible New Directions

  3. Introduction

  4. Objectives • To present simplified analytical models • To discuss the model assumptions with broader audience • To present results generated by heat transfer similarity studies • To collaboratewith AS5562 works Presentation focus • Heat and mass transfer aspects of thermal ice protection of probes • ONLY Aspects of similitude tunnel-flight when testing heated probes • Main reason  Knowledge and experience of the author on heat transfer • NO focus on probes design parameters definition at all • NO focus on failure modes and effects • NO focus on absolute results! Only comparative.

  5. LWC vs. Total Air Temperature (TAT) SUPERCOOLED LIQUID ONLY!!

  6. SAE AS5562 (Draft) Ice and Rain Qualification Standards for Air Data Probes • Under development • Studies based on version “AS5562 draft 3-14-12.doc” • Used only two types of information from AS5562 in present study: • Conditions • Supercooled Liquid, • Ice Crystals • Mixed Phase Icing • Rain • Testing • Operational limitations (similarity guidelines)

  7. Heat and Mass Transfer Tunnel-Flight Similarity • Flow • Reynolds number (Re)  Stanton (St) • Mach (M) • Total Water Collection • Water catch  high beta  tunnel water mass flux • Droplets inertia parameter  high beta  not important • Remaining water runback  water management • Heat and Mass Transfer • Reynolds number (Re)  Stanton (St) • Stanton (St)  analogy  Stanton mass (St_m) • Convective Heat Transfer driven force (DT) • Convective Mass Transfer driven force (mass fractions)

  8. TunnelConditionAdjustment(as per AS5562 3-14-12 draft) : • Altitude Limitation • TAStest = TASref • TATtest = TATref • SATtest = SATref • Airspeed Limitation: • TATtest = TATref • LWCtest= LWCref * TASref/ TAStest • IWCtest = IWCref * TASref/ TAStest • StaticAir Temperature Limitation: • TATtest = TATref • LWCtest = LWCref * TASref/ TAStest • IWCtest = IWCref * TASref/ TAStest But icecrystalsstillneed a model or criteria Applicability range limitsneed to bestudied

  9. SAE AIR1168/4 Model

  10. ModelBasedon AIR1168/4 • Assumptions • Zero-Dimensional (lumpedanalysis) • CollectionEfficiency b = 0.85 • Surfacefullywet F=1 • Impingementarea = total area • Temperaturesabove 0°C • ThinWaterFilm • Runningwet OR Fullyevaporative • Effectsconsidered: • Convection • WaterVaporization • WaterImpingement • No ice fusioneffect • No conductionorotherheatlossess

  11. CFD++ results Plane Y=0 AOA=0°C Side-Slip=0ºC Plane Z=0.025 Collection Efficiency can be used as input Of 1D or 2D more advanced models HOWEVER, present study ASSUMEDconservative value of b=0.85 Plane Z=0

  12. ResultsofModelBasedon AIR1168/4 For surface at 0°C Supercooled liquid water only

  13. Study of Similarity Rules proposed by SAE AS5562

  14. Coupled Heat and Mass Transfer

  15. SimpleEvaporativeCoolingModel • Assumptions • Zero-Dimensional (lumpedanalysis) • CollectionEfficiency b = 0.85 • Surfacefullywet F=1 • Temperaturesabove 0°C • ThinWaterFilm • Runningwet OR Fullyevaporative • Effectsconsidered: • Convection • WaterVaporization • No waterImpingementeffect • No conductionorotherheatlossess • No ice fusioneffect

  16. Coupled Heat and Mass Transfer (Spalding, 1962)

  17. GraphicalMethodofSolution Only liquidphaseconsidered. Need extension for ice crystals and mixed phase

  18. Study of Similarity Rules proposed by SAE AS5562

  19. Effects of Impingement and Ice Crystals

  20. ModifiedEvaporativeCoolingModel • Assumptions • Zero-Dimensional (lumpedanalysis) • CollectionEfficiency b = 0.85 • Surfacefullywet F=1 • Temperaturesabove 0°C • ThinWaterFilm • Runningwet OR Fullyevaporative • AdditionalEffectsconsidered (0thers kept): • WaterImpingementeffect • Ice fusioneffect • Ice CrystalsandMixedPhase • LowConvectionin Enclosed Space insideProbe Tube • InternalProbeAmbientTemperature -5 ºC (Arbitrary, needthermalanalysis)

  21. Envelope StudywithModifiedEvaporativeCoolingModel For surface at 0°C

  22. Study of Similarity Rules proposed by SAE AS5562

  23. Conclusions and Possible New Directions

  24. Conclusions • Simple Evaporative Cooling Model does provide qualitative results that allow trade-off and similarity studies • Modified Evaporative Cooling Model (with ice crystals and water catch) allows: • Analysis of similarity flight-tunnel regarding heat transfer effects • Comparison between air data probe standards/documents conditions in terms of heat load and water catch • The similarity proposed by AS5562 must be complemented by a Thermal Heat Load Analysis, what eventually may lead to probe heater decrease in tunnel

  25. Suggested Next Steps • To perform a thermal analysis to assess the temperature inside the air data probe tube, which must include thermal radiation • To study the transient ice melting problem inside probe tube with supercooled water, ice crystals and mixed phase • To predict the 3D impingement over the probe • To estimate the 3D water runback (film, beads, rivulets) movement and the surface wetness factor • To correlate 3D results in order to used in simple analytical 0-D models

  26. ATS4i Code convection ATS4i Code overall ATS4i Code ATS4i Code end of water film Plan  compare with 2D code results and test data  Need an application case and test data!

  27. Generic Probe Results Need test data for validation!

  28. Collection Efficiency Results from CFD++ Plane Y=0 Plane Z=0.025 Collection Efficiency on Surface Plane Z=0 Generic Probe Results

  29. Evaporation Heat Flux Results after Post-Processing Generic Probe Results Full Evaporative Heat Flux Average  2.6 W/in2 Typical Power Density10 W/in2

  30. Cp Sample Results from CFD++ Generic Probe Results. Sample of Results.

  31. Thank you !Contact: Guilherme da Silva gasilva@ats4i.com.br

  32. Presentation References • Certification/Qualification Documents • Regulations – FAR 25 and TSO C16a • Standards – SAE AS390, SAE AS393, SAE AS403A, SAE AS8006, BSI 2G.135, MIL-T-5421B, MIL-T-5421A, MIL_P-83206, MIL-P-25632B • SAE Standard in preparation • SAE AS5562 (Draft) - Ice and Rain Qualification Standards for Airdata Probes • AC-9C, Air Data Probe Standards Panel, SAE, 2006 (presentation) • AC-9C, Design Requirement Cross Reference List Rev6, SAE (excel spreadsheet) • SAE , SAE Aerospace Applied Thermodynamics Manual, “Ice, Rain, Fog, and Frost Protection”, SAE AIR1168/4, Proposed Draft, 2006 • Spalding, D. B., “Convective Mass Transfer, an Introduction”, McGraw–Hill, New York, 1963. • Duvivier, E. (EASA) “Flight Instrument External Probes”, 1st SAE Aircraft & Engine Icing International Conference, Seville, 2007 (conference presentation)

  33. Further Reading • Mason, J., “The Physics of Clouds”, 2nd Ed., Claredon Press, Oxford, 1971 (book) • Johns, D. (TC Canada), “Future Rulemaking – Ice Protection Harmonization Working Group –Update”, 1st SAE Aircraft & Engine Icing International Conference, Seville, 2007 (conference presentation) • Bernstein, B., Ratvasky , T. P., Miller, D.R., “Freezing Rain as an in-Flight Icing Hazard”, NASA TM--2000-210058, NCAR, Colorado, June (NASA Report) • Jeck, R. K., “Representative Values of Icing-Related Variables Aloft in Freezing Rain and Freezing Drizzle”, DOT/FAA/AR-TN95/119, Federal Aviation Administration, U.S. Department of Transportation,1996 (FAA Technical Note) • Jeck, R. K., “Advances in the Characterization of Supercooled Clouds for Aircraft Icing Applications”, DOT/FAA/AR-07/4, Federal Aviation Administration, U.S. Department of Transportation,2008 (FAA Report) • European Aviation Safety Agency (EASA), ETSO C16 update , Terms of Reference, ToR Task number ETSO.009, Issue 1, August 31, 2009 (EASA document) • Ice Protection Harmonization Working Group (IPHWG), Tasks 5 & 6 Working Group Report, October 2006, Rev A March 2007 (IPHWG report) • Ice Protection Harmonization Working Group (IPHWG), “Task 2 Working Group Report on Supercooled Large Droplet Rulemaking”, December 2005 (IPHWG report)

More Related