February 4, 2016 Telecon Slides (pre-telecon). Telecon agenda, February 4, 2015 Review since last telecon Administrivia Dates Website Other happenings

February 4, 2016

Telecon Slides (pre-telecon)

2

Telecon agenda, February 4, 2015• Review since last telecon• Administrivia

• Dates• Website• Other happenings

• What do we need to do next?• Workshop summary, in brief• Technical issues that we want to discuss

• Your technical issue that you want to discuss goes here• DDES grid now available• Flutter boundary exploration with FUN3D

• Workshop debrief discussion• What would we have liked to be different?• What did we learn?• What is being re-analyzed? (From whom should we be expecting additional results?)

• Next telecon March 3, 11 a.m.

3

Summary since Dec telecon

• Website address: http://nescacademy.nasa.gov/workshops/AePW2/public/• Last telecon prior to workshop held Dec 3, 2015 11 a.m.• Matrix of results submitted by telecon were reviewed• Discussion panel discussed- panel moderator, participants, title were confirmed• Next telecon March 3, 11 a.m. East Coast time in U.S.

• Data submittal spreadsheets fed back to analysis teams with detailed instructions• Workshop held Jan 2-3, associated with AIAA SciTech conference; organizational

aspects provided by Megan Scheidt• Discussion Panel held at SciTech, Jan 5 (Heeg, Raveh, Chwalowski, Righi,

Schuster); organizational aspects provided by Joe Slater• Report out to Structural Dynamics Technical Committee (Daniella Raveh, Jan 6)• Special session at SciTech Jan 2017: request submitted by Alessandro Scotti to

Zahra Sotoudeh (SDTC lead for SciTech). Note that the SDTC chairmanship will turn over this year from Bruce Willis to Chad Hebert.

4

Special Session at SciTech 2017TITLE: Special Session: 2nd Aeroelastic Prediction Workshop - Results and Lesson Learned

DESCRIPTION:

The session aims at exploiting the results obtained from the computational teams who participated to the second Aeroelastic prediction workshop organized by AIAA during the days before SciTech 2016.

Due to the timing and nature of the workshop itself (which is ending by March 2016), it is foreseen that the computational teams do revise their predictions and methods to provide a full insight on their efforts during this last year by means of a properly deserved publication. Being the amount of data to be analyzed and checked really wide, the proposed special session which will be held during the upcoming Aviation Conference will not be sufficient to computational team to provide the whole picture of the prediction effort, also in view of the difficulties related to the physical problem to be solved.

The Workshop saw a wide participation of attendees from many different countries; many different codes and methodologies were adopted both with an academic or an industrial approach.

The following panel discussion held on Tuesday 5th Jan., saw moreover, great participation, and a warm discussion led to the conclusion that still more work has to be done on both the computational and exploitation side.

The nature of the physical problem which had to be solved is way far from being trivial and it is of vital importance either on academic and industrial worlds, as it assess the practical boundaries of the tools and methodologies currently being used/developed, providing wide indication of the reliability of the predictions themselves.

From this point of view this represents for sure the best meeting point between academia and industry, melting both worlds into a valuable and prolific discussion on the way forward for tools and methodologies development.

For this reason a devoted session during the next Scitech will allow all the teams who participated to the workshop in clear exploitation of the methodologies the results and the issues faced during their computation efforts.

POTENTIAL PAPERS:

Papers are foreseen from different teams who already presented results during the two days workshop.

It is possible to foresee an historical paper describing the test case which has been analyzed within the workshop (NASA Langley), at least 3/4 papers from the teams who took part to the computational prediction (NASA Langley, FOI, NLR, EMBRAER, Technion - ISCFDC, CD-ADAPCO, ANSYS, University Michigan, ZAHW, ATA Engineering, PoliMI) and most likely a concluding paper (NASA & Participant Computational Teams), summarizing the whole database of results highlighting the status of computational aeroelasticity in predicting flutter and aeroelastic phenomena with and without the support of wind tunnel data.

SciTech 20179-13 January 2017, Grapevine, Texas

January 2-3, 2016

Aeroelastic Prediction Workshop Schedule

Key Dates: • Computational Team Telecons: 1st Thursday of every calendar month 11 a.m. EST • Re-analysis (and data set completion) results due Feb 28, 2016• Database needs to be generated by March 31, 2016 so that comparison data can be used in

publications at Aviation conference • 2016 AIAA Aviation Conference:

• Manuscript Deadline: 10 May 2016• Conference: June 13-17, Washington D.C.

• 2017 AIAA SciTech Conference Abstract Deadline ~ June 1, 2016

6







7

From May 2015 Telecon Slides:Envisioned Workshop Process for Analysis Teams

• Perform analyses• Submit results • Prepare informal presentations for workshop• SciTech 2016

• AePW-2• Present results• Results comparisons• Discussion of results• Path forward

• Panel discussion???• Re-analyze• Publish at special sessions of conferences (which conferences?)• Publish combined journal articles

8

Next Steps• Correct results / Finish submitting results that were presented at the workshop• Re-analysis (Scope this gently so that it can be finished and submitted by Feb 28)• Submit results• Aviation special session• Planning for SciTech special session

• Going beyond AePW-2 to learn more about:• Numerical damping effects (including temporal convergence requirement, influence of limiter)• Does coupling method matter?• Influence of separation? Do we have additional analyses, codes that can be applied to the Mach 0.85 5 deg case?• Analysis across the Mach-alpha envelope• Separate the effects of shock strength, shock location, lower surface aft loading• Turbulence Models: Can we follow some of the logic and wisdom that Yuval offered?• Higher fidelity analysis tools

9January 2-3, 2016

Data file submittal status (Not updated for Feb 4 Telecon- will be sent by email when available)

Case1 Case2 Case 3

Coarse Medium Fine Coarse Medium Fine Coarse Medium Fine

Embraer x x x x (2a only) x x*

ANSYS xxxx xxxx xxxx xx (2a only) xx xx

Technion x xxx x x

Umich x x x x

Ustrasbourg

ZHAW x x x x xx

FOI x x

ATA x x x x x

NASA x x x x x x x x

Light blue background: New files received since Nov 19 telecon.

Jen- Need to update this to include types of data received for each case.Update to reflect current data set status

10

Next steps- Submitting Data and Re-analysis Results• Submit your results: 3 options for data files

1. Convert your data into database format. This must be exact so that the plotting and sorting programs can utilize the data. It must also contain the subcase identification information. (Ask for the matlab functions: assign_subcase.m and possible_answers.m)

2. Submit your data exactly as before. If your data sets have already been processed, please don’t vary the format, variable names, etc. Your files already have a tedious set of unique functions to convert them into database format. If you add variables, please note that in the email. (e.g. if you have now computed the sectional coefficients but they weren’t in the original data set, please indicate this in the email.)

3. You can duplicate the format being used by someone whose data has already been processed. It has to be exactly the same though. Any changes (improvements?) will break the codes used to process the data files.

• Notes regarding correcting errors in submitted data sets o Errors in data sets that were submitted and processed include:

1. Sign changes were applied to the pressure coefficient data so that Cp could be plotted without changing the axis orientation (some of the analyses applied this only to the static data submitted. Others left this sign change when processing the FRFs.)

2. The pitching moment was used an incorrect reference point. 3. The data had wasn’t ordered such that it could be compared and/or (i.e. it wasn’t sorted upper/lower properly in some cases, in other cases it

wasn’t sorted in a continuous progression along the chord). 4. Data was misidentified by the variable names used.

o In all cases, when you fix these things, we need to be very careful to identify which files they are replacing and why (the corrections are part of the database generation at this stage and will continue to be applied to all of your data unless we specify that the files have had the corrections made.). It will be very confusing if you only fix SOME of the results and not ALL of them.

• Follow the instructions regarding the spreadsheets. Most of the information on the spreadsheets is turned into the database that serves as

• Data• Data identification• Data sorting parameters

o Some of the cells are for comments so that the additional data files can be understood and manipulated into the database. These cells can be text, paragraphs, etc. If it isn’t obvious that a box is for comments like this, it probably isn’t. Look at the example files that were distributed sorting.

11

Next steps- Submitting Data and Re-analysis Results

• Submit your results: 3 options for data files1. Convert your data into database format. This must be exact so that the plotting and sorting

programs can utilize the data. It must also contain the subcase identification information. (Ask for the matlab functions: assign_subcase.m and possible_answers.m)

2. Submit your data exactly as before. If your data sets have already been processed, please don’t vary the format, variable names, etc. Your files already have a tedious set of unique functions to convert them into database format. If you add variables, please note that in the email. (e.g. if you have now computed the sectional coefficients but they weren’t in the original data set, please indicate this in the email.)

3. You can duplicate the format being used by someone whose data has already been processed. It has to be exactly the same though. Any changes (improvements?) will break the codes used to process the data files.

12

Next steps- Submitting Data and Re-analysis Results• Notes regarding correcting errors in submitted data sets

o Errors in data sets that were submitted and processed include: 1.Sign changes were applied to the pressure coefficient data so that Cp could be

plotted without changing the axis orientation (some of the analyses applied this only to the static data submitted. Others left this sign change when processing the FRFs.)

2.The pitching moment was used an incorrect reference point. 3.The data had wasn’t ordered such that it could be compared and/or (i.e. it wasn’t

sorted upper/lower properly in some cases, in other cases it wasn’t sorted in a continuous progression along the chord).

4.Data was misidentified by the variable names used.oIn all cases, when you fix these things, we need to be very careful to identify which

files they are replacing and why (the corrections are part of the database generation at this stage and will continue to be applied to all of your data unless we specify that the files have had the corrections made.). It will be very confusing if you only fix SOME of the results and not ALL of them.

13

Next steps- Submitting Data and Re-analysis Results

• Follow the instructions regarding the spreadsheets. Most of the information on the spreadsheets is turned into the database that serves as

• Data• Data identification• Data sorting parametersoSome of the cells are for comments so that the additional data files can

be understood and manipulated into the database. These cells can be text, paragraphs, etc. If it isn’t obvious that a box is for comments like this, it probably isn’t. Look at the example files that were distributed sorting.

14



• What do we need to do next?

• Workshop summary, in brief• Technical issues that we want to discuss




15

Big Question Remain• Why do our flutter predictions for Case 3 vary so widely?

• What can we do to understand the underlying causes?• What can we do to improve the predictions?

• Does the coupling methodology matter? (loose vs strong, using AePW-2 language)

• What are the critical features that induce flutter? Do these critical features vary by flow condition? (e.g. Shock formation, separated flow onset, separation-reattachment cycles and phasing, modal interactions)

• Process: • How should we approach flutter solutions using current CFD methodologies?• How should we recommend modification of CFD methodologies to better suit

flutter prediction?

Some big picture comments & questions: Computational

• The process that we used to obtain flutter predictions from FUN3D was improvisational. We need something better.

• Process used required intensive matrix to differentiate Numerical vs Physical damping• Desired:

• Integrated assessment of physical damping prediction• Integrated process to drive system to a physical prediction of damping (rather than the primary result that we seemed to

achieve which is a study of numerical damping)

• What is the “right way” to do temporal convergence? If I had it to do all over again, would I, could I:• Perform Time-accurate analysis of the uncoupled flow field. Drive it until the answers (what parameter?) are constant?• Choose some smarter parameter to examine rather than stability and single degree of freedom appearance of the generalized

displacements and pitch angle?• Find some reduced order method or sensitivity-based analysis to guide the CFD solution process? Convergence studies?• Work harder at the typical section analysis, using those results to perform temporal convergence?

• Spatial convergence / Grid Adaptation for unsteady flows with grid motion: What is the right way?• Unsteady flow modeling: Are there turbulence models appropriate, validated for unsteady flow? • Structure-fluid coupling methodology and timing

• We have one result using EDGE that indicates that this doesn’t matter for the EDGE implementation• Is this code (implementation) dependent? Which codes have similar implementation? Different implementation?

January 2-3, 2016

AePW-2 Analysis Teams & Workshop Statistics

Adam Jirasek and Mats Dalenbring (FOI)Jan Navratil (Brno University of Technology, VUT, Czech Republic)

Yannick Hoarau and C.-K. Huang (ICUBE, Strasbourg University, France)A. Gehri and J. Vos (CFS Engineering, Lausanne, Switzerland)

Eric Blades (ATA Engineering)Tomer Rokita (Aerodynamics department, RD&E Division, RAFAEL)

Balasubramanyam Sasanapuri and Krishna Zore (ANSYS India)Robin Steed (ANSYS Canada)

Eric Bish (ANSYS Inc.)

Marcello Righi (Zurich University of Applied Sciences)

Daniella E. Raveh (Technion IIT)Yuval Levy and Yair Mor Yossef (Israeli CFD Center)

Guilherme Begnini Cleber Spode

Aluísio V. Pantaleão Bruno Guaraldo Neto,

Guilherme O. Marcório,Marcos H.J. Pedras

Carlos Alberto Bones(Embraer)

Pawel Chwalowski and Jennifer Heeg (NASA)

Eirikur JonssonCharles A. Mader

Joaquim R.R.A. Martins(University of Michigan)

Sergio Ricci and Andrea Mannarino(Department of Aerospace Science and Technology of Politecnico di Milano)

Patrick McGahGirish Bhandari

Alan MuellerDurrell Rittenberg

(CD-adapco)Amin Fereidooni and Anant Grewal (NRC)

Marcel Grzeszczyk (NRC, University of Toronto)

Bimo Pranata and Bart Eussen (NLR)

Eduardo Molena (ITA)

47 workshop participants

AePW-2 Analysis Codes Utilized

LinearRANS,

UncoupledEuler,

CoupledRANS,

CoupledHybrid

RANS/LES

• MSC NASTRAN • SU2 • OpenFoam

• CFD++• Aero• EZNSS• Edge• FUN3D • Edge• EZAir • FUN3D• Star_CCM+ • EZAir• Loci/Chem• Fluent• CFX• SUMAD• ENFLOW• NSMB

From: AePW-2 workshop presentation by Yuval Levy “Turbulence Model Effects”

AePW-2 Flutter Onset SummaryCase 1 Case 2 Case 3

Mach 0.7 0.74 0.85Angle of attack

3 0 5

• Less challenging flow • Experimental value known

• Very challenging flow • Blind test case

NASA Management Highlight• Computational predictions of flutter

onset showed good agreement with experimental data for the designated benchmarking test case (low transonic Mach number, 0°angle of attack (pink line in figure). Weak shocks and small separated flow regions were predicted at this condition.

• Linear predictions produced comparable results at this condition (blue line in figure).

• At the more aggressive optional analysis condition, where no experimental flutter onset data is available and the predicted flow conditions include strong shocks with dominant separated flow regions, the predictions varied widely (orange line in figure).

Ranges of High-FidelityComputational Results

Mach 0.74Mach 0.85

Linear AnalysisResultsExperimentTDT operatingenvelope

There is still a lot of data reduction to be done

60% span

V

Case 2c_qFMach 0.74, a =

0°

These comparisons are utilizing the preliminary data, as submitted prior to the AePW. These are workshop results, not publication results. Please use these results showing proper respect for the willingness of the analysts and data reduction team to share preliminary findings.

Experimental data Experiment boundsColored lines with open symbols:• Each analysis team shown by a separate color• Each grid size shown by a different symbol

Upper Surface Lower Surface

Traceability: We have to examine and compare our results based on intermediate physics to understand the variation in predictions and gain further insights.What are better parameters to examine, quantify?

23



• What do we need to do next?• Workshop summary, in brief

• Technical issues that we want to discuss• Your technical issue that you want to discuss goes here• DDES grid now available• Flutter boundary exploration with FUN3D



AePW-2 Case 3C

AePW-2 BSCW Fine Grid: ~27M nodes Towards DDES Analysis ~35M

New grid available for performing Higher fidelity simulationsURANS SA vs. DDES

AePW-2 Case 3C, AoA = 5deg

27





• Workshop debrief discussion• What would we have liked to be different?• What did we learn?• What is being re-analyzed? (From whom should we be expecting additional

results?)• Next telecon March 3, 11 a.m.

Workshop debrief notes go here

29January 2-3, 2016

General material and prior telecon summaries

30

Updated analysis parameter table

Nov 19 telecon summary

• Held on Nov 19, 2015 11 a.m.• Next telecon Dec 3, 11 a.m. East Coast time in U.S.• Aviation conference special session approved. 8 abstracts submitted for session• Panel session for SciTech is on the agenda for Tuesday afternoon, Jan 5

• Discussed format, questions, moderator

• Status of data submittals to date (Nov 19) • Data submittal Q&A• Brief discussion of workshop agenda

31

October telecon summary

• Held on Oct 1, 2015 11 a.m.• Next telecon November, 19 11 a.m. East Coast time in U.S.• Administrative matters

• Workshop registration is open on AIAA website• Possible special session at Aviation discussed, interest solicited. 5 teams

responded positively on the telecon.• Problems with the telecon number in Italy. Andrea Mannarino, Politecnico di

Milano was going to discuss Case 2: Euler Results. Defer until Nov telecon

• Analysis results• Case 1 FRFs submitted by 4 teams; comparison plots are

included in the Oct telecon slides• Added new results to Case 1 Integrated coefficients plots

(included in this file)• Processing discussion:

• Process overview and details32

September telecon summary

• Held on Sept 3, 2015 11 a.m.• Next telecon November, 5 11 a.m. East Coast time in U.S.• Administrative matters

• Telecon slides now uploaded to website• Deadline established for declaring participation as an analysis team: Oct 1• Advertisement blurb submitted to AIAA

• Analysis results• Embraer discussed results for Case 1, both steady and forced

oscillation FRFs• Comparisons of steady coefficients for Case 1 were presented and

discussed. Results separated by turbulence model, grid size and grid source are included in the Sept telecon slides.

• Consistent turbulence model study added to the analysis matrix: Case 2: Flutter at Mach 0.74, 0° angle of attack. For those running RANS analysis, utilize your code’s standard Spalart-Allmaras turbulence model

33

August telecon summary

• Held on August 6, 2015 11 a.m.• Next telecon October 1, 11 a.m. East Coast time in U.S.• Administrative matters


• Analysis results• Jennifer Heeg showed (July telecon) unforced unsteady results for Case 3 (Mach

0.85, 5°); Shock motion of ~9% of the chord for the unforced (no excitation) system is very similar using:

• EZNSS hybrid DDES (based on k-w SST) , shown by Daniella Raveh on June telecon• FUN3D RANS + SA • FUN3D URANS + SA

• Jennifer Heeg discussed (August telecon) frequency response function (FRF)• Consistent turbulence model study added to the analysis matrix: Case 2:

Flutter at Mach 0.74, 0° angle of attack. For those running RANS analysis, utilize your code’s standard Spalart-Allmaras turbulence model

• Discussed the format and content of the panel discussion for SciTech34

July telecon summary

• Held on July 2, 2015 11 a.m.• Next telecon August 6, 11 a.m. East Coast time in U.S.• Administrative matters


• Analysis results• Krishna Zore from ANSYS shared results- phase difference relative to experimental data

noted; may be definition • Jennifer Heeg showed unforced unsteady results for Case 3 (Mach 0.85, 5°); Shock

motion of ~9% of the chord for the unforced (no excitation) system is very similar using:• EZNSS hybrid DDES (based on k-w SST) , shown by Daniella Raveh on June telecon• FUN3D RANS + SA • FUN3D URANS + SA

• Daniella Raveh from Technion showed results on the June telecon for Case 3: EZNSS RANS solutions showed dependence on the turbulence model

• Consistent turbulence model study added to the analysis matrix: Case 2: Flutter at Mach 0.74, 0° angle of attack. For those running RANS analysis, utilize your code’s standard Spalart-Allmaras turbulence model

• Discussed the format and content of the panel discussion for SciTech35

June telecon summary

• Held on June 11, 2015 11 a.m.• Next telecon July 2, 11 a.m. East Coast time in U.S.• Administrative matters

• Analysis team matrix updates continue• Introduced SciTech panel discussion

• Analysis results

Marcello Righi, Zurich University of Applied Sciences (ZHAW, ZUAS) • Case 1: showed results using Edge and SU2

• Unforced system shown as both average results from dynamic case and steady analysis• Frequency response functions at forcing frequency & at higher harmonics; showed disagreement in

the shock/divot region

Daniella Raveh, Technion: • Cases 2: Varied time step size, temporal convergence criteria and turbulence model

• Flutter frequency was slightly lower with a finer mesh; • temporal convergence study showed increased damping with decreased time step size; “good enough” declared at time step size of

0.00024 seconds• turbulence model changed the damping• Solution hasn’t converged to an oscillatory behavior at 1.5 seconds (~ 6 cycles); more iterations (global time steps) are needed

• Case 3: hybrid DDES shows unsteady flow with shock motion36

37

May telecon summary

• Held on May 7, 2015 11 a.m.• Next telecon June 11, 11 a.m. East Coast time in U.S.• Discussed administrative matters

• AIAA coordination: Workshop will be held Saturday Jan 2 (3pm-6pm) & Sunday Jan 3 (8am-6pm)

• Workshop process• Workshop agenda• Discussed having a panel / discussion session at SciTech- during the conference

week• Analysis team matrix updates continue• Suggested face to face at AIAA Aviation conference- not a lot of anticipated

participation

• Corrected & updated workshop information from May• Units on stiffness values

• Kh = 2637 lb/ft = 219.75 lb/in = 219.75 slinch/sec^2• Ktheta = 2964 ft-lb/rad = 35568 in-lb/rad= 35568 slinch-in^2/s^2/rad

• Corrected Reynolds number for Case 1 (Mach 0.7, 3°)• Rec = 4.56x106; Re = 3.456x106

38January 2-3, 2016

AIAA Interactions

Approved and signed off byBruce Willis, Chairman of Structural Dynamics Technical CommitteeMegan Scheidt, Managing Director of Products and Programs

39

Envisioned Workshop Process for Analysis Teams (May, 2015)• Perform analyses• Submit results • Prepare informal presentations for workshop• SciTech 2016

• AePW-2• Present results• Results comparisons• Discussion of results• Path forward

• Panel discussion???• Re-analyze• Publish at special sessions of conferences (which conferences?)• Publish combined journal articles

40

April telecon summary

• Held on April 2, 2015 11 a.m.• Next telecon May 7, 11 a.m. East Coast time in U.S.• Updated analysis parameters matrix; uploaded to website• Experimental data was added to website• List of analysis teams produced• Discussion of workshop dates• Experimental data reduction showing “divot” in the FRFs to likely

be physical• Pawel showed animation of flutter solution at Mach 0.74 using

FUN3D

41

March telecon summary• Website address: http://nescacademy.nasa.gov/workshops/AePW2/public/• Held on March 12, rather than March 5 (with the usual March daylight savings time issues)• Next telecon April 2, 11 a.m. East Coast time in U.S.• SU-2 doesn’t have existing FSI capability.(Melike and Dave Schuster to talk about this?)• Block-structured grids from AePW-1 are available, generated by Thorsten Hansen at ANSYS.

(Thorsten and Pawel will work together to make those available on the new website.)• The molecular weight of R-134a isn’t the same as a standard property table shows (102 g/mol). The

value derived using the listed properties is more like 98 g/mol. This is due to the practical issue of gas purity that is achieved in the wind tunnel. The values on the table are from the test data, where the purity was likely 95%’ish. (Pawel will add a line for molecular weight to the analysis parameters table.)

• Add the following to the table of analyses:• ATA Engineering (Eric Blades will run LoPsiChem)• AFRL (Rick Graves will run FUN3D)• Milano Polytechnico (Sergio Ricci will run numerous codes)

• Please send comments regarding the distributed slides. In particular, are you okay with the abstract submittal form?

• With regard to submitting data to the workshop for comparison:• Can you provide results in matlab?• How do you feel about providing them in a data structure in matlab?

• Doublet lattice aeroelastic solution results:• Bimo and Jen will work to present the results to date at the next telecon• We will put the bulk data file, including the aero model and the flutter cards on the web site. This can serve as a basis for those who might

want to use correction methods, etc.

• Temporal convergence results• Organizations may not have the resources to perform the temporal convergence study for all grids. It is suggested that this be done for a grid

resolution where things look to be spatially converged. Experience at NASA has shown qualitatively different results for the unstructured coarse grid than those observed for the finer grid resolutions.

• The flutter results at low Mach number (Mach 0.74) have shown great variation with regard to time step size. The predicted aeroelasticity stability of the system has been shown to be a function of the time step size and the subiteration convergence level.

42

March telecon summary• Website address: http://nescacademy.nasa.gov/workshops/AePW2/public/• Held on March 12, rather than March 5 (with the usual March daylight savings time issues)• Next telecon April 2, 11 a.m. East Coast time in U.S.• SU-2 doesn’t have existing FSI capability.(Melike and Dave Schuster to talk about this?)• Block-structured grids from AePW-1 are available, generated by Thorsten Hansen at ANSYS.

(Thorsten and Pawel will work together to make those available on the new website.)• The molecular weight of R-134a isn’t the same as a standard property table shows (102 g/mol). The

value derived using the listed properties is more like 98 g/mol. This is due to the practical issue of gas purity that is achieved in the wind tunnel. The values on the table are from the test data, where the purity was likely 95%’ish. (Pawel will add a line for molecular weight to the analysis parameters table.)

• Add the following to the table of analyses:• ATA Engineering (Eric Blades will run LoPsiChem)• AFRL (Rick Graves will run FUN3D)• Milano Polytechnico (Sergio Ricci will run numerous codes)

• Please send comments regarding the distributed slides. In particular, are you okay with the abstract submittal form?

• With regard to submitting data to the workshop for comparison:• Can you provide results in matlab?• How do you feel about providing them in a data structure in matlab?

• Doublet lattice aeroelastic solution results:• Bimo and Jen will work to present the results to date at the next telecon• We will put the bulk data file, including the aero model and the flutter cards on the web site. This can serve as a basis for those who might

want to use correction methods, etc.

• Temporal convergence results• Organizations may not have the resources to perform the temporal convergence study for all grids. It is suggested that this be done for a grid

resolution where things look to be spatially converged. Experience at NASA has shown qualitatively different results for the unstructured coarse grid than those observed for the finer grid resolutions.

• The flutter results at low Mach number (Mach 0.74) have shown great variation with regard to time step size. The predicted aeroelasticity stability of the system has been shown to be a function of the time step size and the subiteration convergence level.

Feb Telecon Notes• Attendees list (to be added)

• Suggested adding to website:• Participating teams and matrix with contact information• Experimental data (Action item taken by Jen.)

• Request made that the frequency response function information be available in both rectangular form (Re and Im components) as well as in polar (Mag and phase) form. (Action item taken by Jen.)

• Experimental results for Case 1. In the FRF magnitude, there is a sawtooth near the leading edge. What is the source of that? Physical? Sensor issue? (Action item taken by Jen.)

• Grids: structured grids were generated by NASA in plot3D format using Pointwise. The gridding guidelines still include the RSW and HIRENASD from AePW-1. Need to revise them so that they are not confusing. Revisit them also with regard to the Reynolds number.

• Nonlinear effects and LCO:• Discussion regarding hysteresis and identification of the neutral stability point• Discussion about experimental data sets, including a DLR study on LCO where there were trends with Mach number

• Process: • Think about what questions we are trying to answer• How do we tell the organizing committee that we are participating by performing analyses? Is there a website sign up or

abstract submittal form that we mail?

• Note: following the end of the telecon, as the webex window was closing… it was noted that there were some questions and/or comments on the webex communication window. Apologies for not noticing them. The window closed before we could stop it. We are not smart enough to figure out the now-erased questions. Can you ask them again?


44January 2-3, 2016

Mini-abstract from AePW-1

MRL and USF Contribution to AePW - 1N. N. Thusiast_

Multielement Research Lab, Mail Stop 000, Happy Forks, VA 00000 email: [email protected], (777) 777-7777Soar N. Air†

University of Southern Flight, Mail Code 98765, Lofty Heights, TX 00000 email: [email protected], (888) 888-8888

We intend to participate in the AePW-1, to be held April 21-22 2012 in Honolulu, HI. We plan to perform the following sets of computations:

Configuration 1 – RSW , Steady Case, i. M=.825, a=2 degCode: RANS-CFD-3DGrid: Str-OnetoOne-C-v1 (supplied by AePW-1 committee)Turbulence model: Menter SST

Configuration 1 – RSW , Unsteady Case, i. M=.825, a=2 deg, 10 Hz Same as above

Configuration 2 – BSCW, Steady case, M=.85, a=5 deg, 10 Hz Same as above

Configuration 2 – BSCW, Unteady case, M=.85, a=5 deg, 20 Hz Same as above

Configuration 3 - HIRENASD Configuration, steady, M=.8, Re=7 million, a =1.5 degCode: RANS-CFD-3DAeGrid: Str-OnetoOne-C-v1 (supplied by AePW-1 committee)Turbulence model: S-A

We plan to submit our results electronically by the March 20, 2012 deadline to the AePW-1 committee. RANS-CFD-3DAe is a Reynolds-averaged Navier-Stokes code developed by Et et al.,1 widely used at the

Multielement Research Lab. It is specifically formulated to work on three-element wing configurations. Ituses point-matched grids, and is an upwind finite-volume structured code.LES-CFD-3D is a large-eddy simulation code developed at the University of Southern Flight.2 It employs 6th order central differencing in space and 3rd order temporal differencing, along with 9th order

explicit filtering.

ReferencesEt, H., Cet, P., and Era L., “Description of RANS-CFD-3D,” Journal of Codes, Vol. 6, No. 5, 1994, pp. 5– 21.Author, A. and Author B., “Description of LES-CFD-3D,” Journal of Lengthy Papers, Vol. 9, No. 2, 2008, pp. 22–1021.

_ Corresponding Author. Senior Research Scientist, High Lift Branch.† Professor and Chair, Dept. of Aeronautical Engineering.1 of

mailto:[email protected]

mailto:[email protected]

Acknowledgements• Megan Scheidt, AIAA, organizing and coordinating• Joe Slater, Bruce Willis, Dale Pitt, Structural Dynamics TC, sponsorship, coordination, general

support• Organizing committee for doing preliminary analysis and preparations.

• Pawel Chwalowski, NASA• Adam Jirasek, FOI• Daniella Raveh, Technion • Mats Dalenbring, FOI• Alessandro Scotti, Pilatus• Dave Schuster, NESC, NASA• Jennifer Heeg, NASA

• Analysis team leaders and members• Code development teams whose work we have utilized in performing these analyses• Projects, programs and companies funding this work• Workshop participants for insightful and lively discussions

January 2-3, 2016

Goals in data reduction: (these are plots from AePW-1 data reduction effort for HIRENASD)

Documents

February 4, 2016 Telecon Slides (pre-telecon). Telecon agenda, February 4, 2015 Review since last telecon Administrivia Dates Website Other happenings