| 1. Report No.DOT/FAA/TC-24/42 | 2. Government Accession No. | 3. Recipient's Catalog No. |
| 4. Title and SubtitleElectric Vertical Takeoff and Landing (eVTOL) DOWNWASH AND OUTWASHSURVEYS | 5. Report DateDecember 2024 |
| 6. Performing Organization Code |
| 7. Author(s)Maria J. Muia, PhD*, Joshua Stanley*, Todd Anderson*, David Hall*, ZacharyShuman*, Jan Goericke**, Jagdeep Batther**, Zoren Habana**, Chengjin He**,and Hossein Saberi** | 8. Performing Organization Report No. |
| 9. Performing Organization Name and Address* Woolpert, Inc. **Advanced Rotorcraft Technology, Inc. (ART)4454 Idea Center Boulevard 6757 Fremont BlvdDayton, OH 45430 Fremont, CA 94538 | 10. Work Unit No. (TRAIS) |
| 11. Contract or Grant No. |
| 12. Sponsoring Agency Name and AddressDepartment of TransportationFederal Aviation AdministrationOffice of Airports Safety and Standards800 Independence Avenue, S.W.Washington, DC 20591 | 13. Type of Report and Period CoveredFinal Report |
| 14. Sponsoring Agency CodeAAS-100 |
| 15. Supplementary NotesThe Federal Aviation Administration Aviation Research Division CORs were Ryan King and Russ Gorman. |
| 16. AbstractAs part of the Federal Aviation Administration's (FAA) efort to establish vertiport design guidance for facilities intended toaccept powere i and special las rotorcra t is of gring iportance todeterine the risk factors rlated tovertical tkoffand landing (VTOL) operations and how to mitigate them.The airlow generated from the aircraft's rotors/propellers duringtakeoff and landing, nown as downwash and outwash (DWW), can pose sigificant risks to people and propert in the vicinityof aircraft operations. Downwash is the vertical, downward fow of air produced by rotors/propellrs while outwash is the lateralradial, outward airflow that occurs as the downwash contacts the landing surface. The negative impacts of DWOW may beexacerbated at vertiport locations in urban areas where high-volume, high-tempo operations are proposed because of the densepopulations and higher throughput in those areas. However, current research on the effects and mitigation of DW is limited.This report describes the collection and analysis of VTOL DWOW data and the need to mitigate associated risks.The most reliable way to obtain eVTOL DWOW data is from ful-scale aircraft surveys. This research measured the DWOW ofthree prototype eVTOL airraft for their maximum velocity at various locations on a vertiport. A ground-level aray and a verticalarray of ultrasonic three-dimensional anemometers were used for colleting the DWOW wind velocities. The DWOW surveyswere performed at various times and locations and conducted under daylight visual meteorlogical conditions. DWW wind datawere collected at each anemometer location on the ground or vertical sensor aray. The aircraft pilts performed several presetmaneuvers within the bounds of their respective aircraft fight envelopes.Analysis of the result included maximum instantaneusvelcities, moving means and moving standard deviations based on a 3-second ime frame, and a 3-second moving 95 percentile.The survey measurements for the three prototype eVTOL aircraf included in the research were compared to viscous vortexparticle method modeling and simulation where possible. |
| 17. Key Words 18. Distribution StatementElectric vertical takeoff and landing, eVTOL, Advanced air This document is available to the U.S. public through themobility, AAM, Urban air mobility, UAM, Downwash and National Technical Information Service (NTIS), Springfield,outwash. Virginia 22161. This document is also available from theFederal Aviation Administration William J. Hughes TechnicalCenter at actlibrary.tc.faa.gov. |
| 19. Security Classif. (of this report)Unclassified | 20. Security Classif. (of this page)Unclassified | 21. No. of Pages56 | 22.Price |
## ACKNOWLEDGEMENTS
The authors would like to thank Ryan King and William R. Gorman of the FAA Airport Technology Research and Development Branch for their insight and support. These activities would not have been possible without the willingness of the individual original equipment manufacturers to participate and make their aircraft available for this important aviation safety research. Special appreciation also goes to the individual flight test pilots, flight test support personnel, and the airport facility owners and operators where testing took place.
## TABLE OF CONTENTS
Page
EXECUTIVE SUMMARY ix
1. INTRODUCTION 1
2. DESCRIPTION OF AIRCRAFT ANALYZED 5
3. INSTRUMENTS USED 5
3.1 Horizontal Anemometer Array 6
3.2 Vertical Array 7
3.3 Ambient Anemometer 8
3.4 Data Acquisition System 8
4. SCOPE OF TEST 8
5. METHODOLOGY 8
6. RESULTS 10
6.1 eVTOL #1 10
6.1.1 eVTOL #1 Horizontal Array Velocity Results 11
6.1.2 eVTOL #1 Comparison to VVPM Modeling and Simulation 13
6.2 eVTOL #2 15
6.2.1 eVtOL #2 Horizontal Array Velocity Results 17
6.2.2 eVTOL #2 Vertical Array Velocity Results 19
6.2.3 eVTOL #2 Comparison to VVPM Modeling and Simulation 20
6.3 eVTOL #3 34
6.3.1 eVTOL #3 Horizontal Array Velocity Results 35
6.3.2 eVTOL #3 Comparison to VVPM Modeling and Simulation 36
6.4 eVTOL #4 38
7. CONCLUSIONS 40
7.1 Modeling and Simulation 40
7.2 DWOW Velocities 41
8. REFERENCES 44
## LIST OF FIGURES
Figure Page
1 Example Wind Velocity and Blade Frequency Modeled 6
2 Ground Sensor Mounting 7
3 Vertical Array Mobile Cart 7
4 eVTOL #1 Maximum Velocity Recorded at Each Sensor Across All Surveys
in Plan View 12
5 eVTOL #1 Line Graph of Maximum Velocity Recorded at Each Sensor for
Each Survey 13
6 eVTOL #1 Modeled Total Velocity at 23 ft 14
7 eVTOL #1 Modeled Total Velocity at 46 ft 14
8 eVTOL #1 Modeled Total Velocity at 69 ft 15
9 eVTOL #2 Maximum Velocity Recorded at Each Sensor Across all Surveys
in Plan View 18
10 eVTOL #2 Line Graph of Maximum Velocity Recorded at Each Sensor
for Each Survey 19
11 Velocity Predictions at Sensor A2-S10 23
12 Velocity Predictions at Sensor A2-S20 23
13 Velocity Predictions at Sensor A2-S30 24
14 Velocity Predictions at Sensor B1-M40 24
15 Velocity Predictions at Sensor B1-M50 25
16 Velocity Predictions at Sensor C2-S10 25
17 Velocity Predictions at Sensor A2-S10 26
18 Velocity Predictions at Sensor A2-S20 27
19 Velocity Predictions at Sensor A2-S30 27
20 Velocity Predictions at Sensor B1-M40 28
21 Velocity Predictions at Sensor B1-M50 28
22 Velocity Predictions at Sensor C2-S10 29
23 Vertical Array Sensor Configuration 31
24 Tethered Test Case Correlation—Boxplots of Velocity Magnitude 32
25 Tethered Test Case Correlation—Time Histories of Velocity of Magnitudes 33
26 eVTOL #3 Maximum Velocity Recorded at Each Sensor Across All Surveys
in Plan View 35
27 eVTOL #3 Line Graph of Maximum Velocity Recorded at Each Sensor for
Each Survey 36
28 eVTOL #3 VVPM Resolution Sensitivity Study 37
29 Hybrid Method 38
30 Flow Field Sampling Points 39
31 Velocity Profile at 90° Radial 39
32 Maximum Velocity Measured by Sensor Distance to TLOF Center for All
eVTOL Aircraft Surveyed 42
## LIST OF TABLES
1 Beaufort Wind Scale 1
2 Air Velocity Sensitivity Thresholds 3
3 Sensor Information from VVPM DWOW Simulation 5
4 Pilot Flight Tolerances 8
5 Data Summary Statistics Legend 9
6 eVTOL #1 Sensor Labels and Distances 10
7 eVTOL #1 Flight Details for Each Survey 10
8 eVTOL #1 Maximum Velocity Recorded at Each Sensor Across All Surveys 12
9 eVTOL #2 Sensor Labels and Distances 15
10 eVTOL #2 Flight Details for Each Survey 16
11 eVTOL #2 Maximum Velocity Recorded at Each Sensor Across All Surveys 19
12 eVTOL #2 Maximum Velocity Recorded for All Surveys 20
13 eVTOL #3 Sensor Labels and Distances 34
14 eVTOL #3 Flight Details for Each Survey 34
15 eVTOL #3 Maximum Velocity Recorded at Each Sensor Across All Surveys 36
16 Highest DWOW Velocity Measured 41
17 Overall Maximum Speeds Measured for All eVTOL Aircraft 43
AC Advisory Circular
AGL Above ground level
CFD Computer fluid dynamics
C.F.R. Code of Federal Regulations
DCA Downwash caution area
DWOW Downwash and outwash
EB Engineering Brief
eVTOL Electric vertical takeoff and landing
FAA Federal Aviation Administration
FATO Final approach and takeoff area
GPS Global Positioning System
GPU Graphic processing unit
MTOW Maximum takeoff weight
NASA National Aeronautics and Space Administration
NOAA National Oceanic and Atmospheric Administration
OEM Original equipment manufacturer
SA Safety area
TLOF Touchdown and liftoff area
VVPM Viscous vortex particle method
WMO World Meteorological Organization
## EXECUTIVE SUMMARY
Electric vertical takeoff and landing (eVTOL) aircraft designs are emerging as a technology poised to increase mobility and simplify air travel. However, because the technology is new, research regarding the risks and dangers is limited. Very little data are available on the effects and potential risks of eVTOL aircraft including downwash and outwash (DWOW), which is the vertical airflow created by a rotor/propeller (downwash) and radial outflow of air once downwash meets the ground (outwash). eVTOL aircraft DWOW can pose significant risks to people and property and must be accounted for in vertiport design. The DWOW of an eVTOL aircraft varies by configuration. The most reliable way to obtain eVTOL DWOW data is from full-scale aircraft surveys. This research included surveys with eVTOL original equipment manufacturers (OEMs) to measure the velocity of their prototype aircraft’s DWOW in vertiport environments that complied with the touchdown and lift-off area (TLOF), final approach and takeoff area (FATO), and the safety area (SA) dimensions outlined in Federal Aviation Administration (FAA) Engineering Brief (EB) 105, Vertiport Design, for a square landing area.
This research employed a custom-made array of ultrasonic, three-dimensional anemometers surrounding the eVTOL vertiport test environment. The TLOF, FATO, and SA were based on the sizes outlined in FAA EB 105 for the controlling dimension of the aircraft being surveyed. GoPro® cameras were mounted outside the safety area to record the survey for reference should it be needed afterward. The DWOW surveys were conducted at various times and locations and performed under daylight, visual meteorological conditions. DWOW wind data were collected at each anemometer location on the ground or vertical sensor array. The eVTOL aircraft pilots performed several preset maneuvers based on input from the pilots and OEMs. Statistics were produced for maximum velocities (instantaneous) and moving means, moving standard deviations, and moving 95 percentiles based on a 3-second time frame. Ambient wind data were collected for reference, but no process was undertaken to subtract the ambient wind velocity from the wind generated by the DWOW.
The survey measurements for the eVTOL aircraft included in the research are compared to viscous vortex particle method (VVPM) modeling and simulation where possible. The current graphic processing unit (GPU) cards available limited the ability to model and simulate these aircraft because of the numerous propeller blades and their proximity to each other. Ultimately, 6 million particles were tracked for 30 revolutions. While particles closer to the aircraft are tracked effectively, their paths did not reach distances where DWOW velocities would be considered safe for people. These current limitations make VVPM alone an unlikely tool for forecasting where people and property will not be affected by high winds. A hybrid approach augmenting VVPM with global mass conservation may prove useful but has not been validated here.
The maximum velocities measured during the surveys taken varied from survey to survey and from aircraft to aircraft. The highest instantaneous maximum measured was almost 100 mph at 41 ft from the TLOF center. The highest moving 3-second 95th percentile was 84 mph at 23 ft from the TLOF center. Speeds of more than 60 mph were measured at 100 ft from the TLOF center.
The eVTOL aircraft surveyed produced high-velocity DWOW flow fields that could easily go beyond the safety area of a vertiport. The high-velocity DWOW of eVTOL aircraft should be considered when designing a vertiport because it can create safety risks to people, aircraft, equipment, and infrastructure, on and off the vertiport. eVTOL OEMs propose high-volume, high-tempo eVTOL operations in urban areas, which have an even greater potential of impacting bystanders with DWOW than traditional helicopters at heliports. In these target areas, the vertiports will likely be surrounded by dense populations in confined spaces and will experience higher throughput. Accordingly, it is recommended to mitigate DWOW by creating a downwash caution area (DCA). The DCA should be operational when and wherever DWOW velocities exceed 34.5 mph.
## 1. INTRODUCTION
Emerging electric vertical takeoff and landing (eVTOL) aircraft designs are abundant, complex, and vary in configuration based on their operational characteristics. These aircraft are positioned to be an industry gamechanger due to their potential for increased mobility. There are very little data on the performance of eVTOL aircraft including the effects of vertical airflow created by a rotor/propeller (downwash) and radial outflow of air once downwash meets the ground (outwash). Because DWOW can cause significant risks including property damage and personal injury, it is important that the Federal Aviation Administration (FAA) take into consideration the downwash and outwash (DWOW) of these aircraft when considering vertiport design guidance. Wind forces from DWOW are a risk to ground crew, passengers, aircraft, and adjacent people and structures (FAA, 2024).
Literature review identified several sources that address the dangers of the winds produced by DWOW. The National Weather Service uses the Beaufort Wind Scale to advise the public on the dangers of winds. Table 1 shows how the Beaufort Wind Scale estimates the strength of wind based on visual cues (National Oceanic and Atmospheric Administration [NOAA], 2023).
WMO = World Meteorological Organization
Table 1. Beaufort Wind Scale
| Force | Wind(mph) | WMOClassification | Appearance of WindEffectsOn Water | Appearance of WindEffectsOn Land |
| 0 | <1 | Calm | Sea surface smooth andmirror-like | Calm, smoke risesvertically |
| 1 | 1-3 | Light Air | Scaly ripples, no foamcrests | Smoke drift indicateswind direction, windvanes are still |
| 2 | 4-7 | Light Breeze | Small wavelets, crestsglassy, no breaking | Wind felt on face,leaves rustle, vanesbegin to move |
| 3 | 8-12 | Gentle Breeze | Large wavelets, crestsbegin to break, scatteredwhitecaps | Leaves and small twigsconstantly moving,light flags extended |
| 4 | 13-18 | ModerateBreeze | Small waves 1–4 ftbecoming longer,numerous whitecaps | Dust, leaves, and loosepaper lifted, small treebranches move |
| 5 | 19-24 | Fresh Breeze | Moderate waves 4–8 fttaking longer form, manywhitecaps, some spray | Small trees begin tosway |
| 6 | 25-31 | Strong Breeze | Larger waves 8–13 ft,whitecaps common, morespray | Larger tree branchesmoving, whistling inwires |
| 7 | 32-38 | Near Gale | Sea heaps up, waves 13–19ft, white foam streaks offbreakers | Whole trees moving,resistance felt walkingagainst wind |
| 8 | 39-46 | Gale | Moderately high (18–25 ft)waves of greater length,edges of crests begin tobreak into spindrift, foamblown in streaks | Twigs breaking offtrees, generallyimpedes progress |
| 9 | 47-54 | Strong Gale | High waves (23–32 ft), seabegins to roll, dense streaksof foam, spray may reducevisibility | Slight structuraldamage occurs, slateblows off roofs |
| 10 | 55-63 | Storm | Very high waves (29–41 ft)with overhanging crests,sea white with denselyblown foam, heavy rolling,lowered visibility | Seldom experienced onland, trees broken oruprooted, "considerablestructural damage" |
| 11 | 64-73 | Violent Storm | Exceptionally high (37–52ft) waves, foam patchescover sea, visibility morereduced | |
| 12 | 74+ | Hurricane | Air filled with foam, wavesover 45 ft, sea completelywhite with driving spray,visibility greatly reduced | |
The FAA’s Rotorwash Analysis Handbook, Volume I – Development and Analysis (Ferguson, 1994), also discusses wind speed thresholds for danger. It indicates “that the majority of downwash and outwash related mishaps could be avoided if separation distances are maintained so that impacting DWOW-generated velocities do not exceed 30 to 40 knots (34.5 to 46.0 mph) across the ground” (Ferguson, 1994). The U.S. Army Research, Development, and Engineering Command Report, Rotorwash Operational Footprint Modeling (Preston et al., 2014), provides similar danger thresholds. Preston et al. (2014) indicate the caution zone for wind velocities for the general population is 33.6 to 44.7 mph while the hazard zone is 44.8 mph and greater, which is in line with the FAA Rotorwash Analysis Handbook. They conclude that rotorwash velocities above 40.3 mph can result in an airport/heliport incident. (Preston et al., 2014)
FAA Advisory Circular (AC) 150/5300-13B, Airport Design (2024), provides guidance for jet blast, which is the jet engine equivalence of DWOW. For airfield planning purposes, the FAA recommends applying the air velocities listed in Table 2, derived from the National Weather Service Beaufort Wind Scale (NOAA, 2023), as sensitivity thresholds at which safety risks increase (FAA, 2024). The items and areas of concern included in Table 2 represent the thresholds in which jet blast air velocities are of concern.
Table 2. Air Velocity Sensitivity Thresholds
| Air Velocity Threshold | Items or Areas of concern |
| 13–18 mph (21–29 km/h) | Unsecured trash, paper, and lightweight debris |
| 24 mph (38 km/h) | Pedestrian areas (e.g., boarding passengers, General Aviationparking areas) |
| 30 mph (48 km/h) | Light objects and empty containers, etc.Ramp personnel (e.g., marshals, baggage handlers) |
| 35 mph (56 km/h) | General area aft of aircraft parking positionService roads and areas adjacent to parking positions and taxiroutes |
| 50 mph (80 km/h) | Area behind aircraft after pushbackGeneral structures, passenger boarding equipment, etc. |
Wind produced from aircraft propulsion units around vertiports can be turbulent and gusty and impact people and property. A sudden gust of wind can trigger a “startle response” where people react suddenly and perhaps put themselves in harm’s way. The FAA describes this as “an uncontrollable, automatic muscle reflex, raised heart rate, blood pressure, etc., elicited by exposure to a sudden, intense event that violates a pilot’s expectations” (FAA, 2017). It is associated with many aviation and other vehicle accidents. During a startle response, the brain skips all the normal sensory processing steps and “takes control of your body to protect you from danger” (Cleveland Clinic, 2023). This can cause a person to overreact to an event. “The ‘startle’ effect of being hit by a transient gust of wind can cause greater upset than being exposed to the same, constant wind velocity, and indeed that buffeting at certain frequencies can excite the human physiological response more easily than others” (Brown, 2023).
Low-to-the-ground, high-velocity winds can also pick up objects and project them through the air. This includes gravel, foreign object debris, and anything not secured to the ground. Such airborne debris can cause damage to aircraft and infrastructure in the vicinity. Dust, dirt, sand, and snow can also become airborne and recirculate through the propeller blades, causing brownout or whiteout environments (Ferguson, 1994). Brownouts and whiteouts can impede visibility and result in a loss of situational awareness.
Because of their potential to create safety risks to people, aircraft, equipment, and infrastructure, on and off the vertiport, the DWOW of eVTOL aircraft should be considered when designing a vertiport. The DWOW from the predecessor to eVTOL, the helicopter, has blown bystanders to the ground, resulting in injury and death (Werfelman, 2023; Australian Transport Safety Bureau, 2023; KABC Television, 2022). Helicopter DWOW has even injured people that the helicopter was sent to rescue (Swarts, 2016). Even when bystanders are aware of the potential for DWOW, they often do not understand the severity and risk associated with it (Werfelman, 2023).
An FAA aeronautical study will be required for most new vertiports as outlined in Title 14 Code of Federal Regulations (C.F.R.) Part 157, Notice of Construction, Alteration, Activation, and Deactivation of Airports. Part 157 states specifically what this study entails:
The FAA will consider matters such as the effects the proposed action would have on existing or contemplated traffic patterns of neighboring airports; the effects the proposed action would have on the existing airspace structure and projected programs of the FAA; and the effects that existing or proposed
manmade objects (on file with the FAA) and natural objects within the affected area would have on the airport proposal. While determinations consider the effects of the proposed action on the safe and efficient use of airspace by aircraft and the safety of persons and property on the ground, the determinations are only advisory. (Notice of Construction, Alteration, Activation, and Deactivation of Airports, 1991)
This study considers the safety of persons and property on the ground, and how DWOW can have a detrimental effect on them. OEMs propose high-volume, high-tempo operations in urban areas. Aircraft operating at vertiports in these areas have even greater potential for impacting bystanders with DWOW than helicopters because they will be surrounded by dense population in confined spaces and experience higher throughput (National Aeronautics and Space Administration [NASA], 2020; FAA, 2023b; Goodrich & Theodore, 2021). Accordingly, DWOW must be mitigated through either vertiport design features or operational procedures.
Vertiport design must consider the possibility of hazardous, high-velocity winds and identify safety measures to mitigate risks to people and property. However, the variances in designs and configuration types, and the complexity of emerging eVTOL aircraft make it difficult to develop a universal model for the prediction of the DWOW flow fields from these aircraft. Research has been conducted to understand rotor DWOW, but this understanding is mostly limited to one- and two-engine and rotary aircraft. The principles of DWOW wake turbulence and how the wake reacts with the surface, surrounding structures, and particularly with multiple other rotors or propellers, as is the case with eVTOL aircraft, is still not fully understood.
Computer modeling has been used extensively to predict the DWOW of single-rotor helicopters. eVTOL aircraft, however, differ significantly from helicopters and vary significantly in design and operational characteristics. Real-world data are limited for eVTOL aircraft compared to helicopters. The number of propellers on eVTOL aircraft and their varying locations make it very difficult to predict their DWOW flow fields, how they interact with each other, and how they interact with the aircraft fuselage. While computer fluid dynamics (CFD) methods, which involve analysis of aircraft performance, can provide impressive results, it can be difficult for use in eVTOL DWOW prediction because of the complexities inherent to eVTOL aircraft configurations with multiple propellers and complicated wake fields. Additionally, CFD methods are expensive and “suffer from gridinduced dissipation errors because of the numerical discretization over the flow field.” Even with advancements in CFD methods, “high computational costs and complicated equation setup still make these methods unfeasible for designers aiming for rapid feedback to optimize their models” (Lee et al., 2022).
Full-scale surveys are the most accurate way to determine the velocities of eVTOL DWOW flow fields on the vertiport environment. Accordingly, surveys were conducted with eVTOL OEMs to measure the velocity of each of their prototype aircraft’s DWOW in vertiport environments that complied with the TLOF, FATO, and the SA dimensions outlined in FAA (2023a) EB 105, Vertiport Design.
## 2. DESCRIPTION OF AIRCRAFT ANALYZED
This research included surveying three eVTOL aircraft, eVTOL #1, eVTOL #2, and eVTOL #3, for DWOW during 2023 and 2024. These aircraft varied in configuration, number of propulsion systems, blades per propulsion unit, and maximum takeoff weight (MTOW), all of which were less than 6,500 lb. They also varied in how they were controlled, by a pilot on board, remotely or computer programmed flight controls. The aircraft were all prototype, preproduction models.
## 3. INSTRUMENTS USED
This research employed three-dimensional, ultrasonic anemometers surrounding the eVTOL vertiport test environment. The TLOF, FATO, and SA were based on the sizes outlined in FAA EB 105 for the controlling dimension of the prototype aircraft being surveyed. GoPro cameras were mounted outside the safety area to record the survey for reference should it be needed afterward.
The selection of the sensors and their locations was predominantly based on preliminary VVPM simulation that was completed for two types of notional eVTOL aircraft. With the first principal formulation, VVPM solves for the vorticity field directly from the vorticityvelocity form of the incompressible Navier-Stokes equations using a Lagrangian approach. This is a natural way of solving vorticity-dominated flows because it only needs to be applied to regions with vorticity and does not require any grid generation effort. It also accurately resolves the vorticity in the flow field for long duration without artificial dissipation, as is often encountered by grid-based CFD solvers, while still capturing the wake distortion and physical diffusion due to air viscosity. It also takes a fraction of the computing time of CFD.
The VVPM and flow field simulations in hover mode and at different heights above the ground predicted wind velocities at various locations around the two notional aircraft. These predictions were to inform the following aspects of survey design:
• Predictions of flow velocities at the notional sensor locations to aid sensor type selection.
Estimate for the unsteadiness of local DWOW velocities at the notional sensor locations and frequency content of the flow for the determination of measurement sampling rate.
• Flow directionality at the sensor location for the definition of a required measurement range of the sensors to be used.
• Recommendation of vertical placement of sensor with the goal of capturing maximum outwash velocities.
Table 3 shows a summary of the sensor requirements determined from VVPM and flow field simulation.
Table 3. Sensor Information from VVPM DWOW Simulation