Database hydrodynamic and aerodynamic profiles

 Interactive data base HELICIEL use XFOIL Download performance data profiles for use in Heliciel Use the interactive data base of Heliciel

## Understand and master the hydrodynamics and aerodynamics profiles Databases:

When we began designing a propeller or a wing , we find ourselves very quickly confronted with the choice of the profile, or rather, profiles, that give shape to our propeller or wing.
• To select a profile aerodynamic or hydrodynamic, we must be able to evaluate its performance in the operating situation we are interested.
The Wright Brothers (1901) were pioneers, not only in flight, but especially in their search for the optimum shape of their wings. For this they built a wind tunnel and performed a series of tests on profile shapes exposed to an air stream of variable speed and noted methodically the forces of Drag and Lift observed. You will find on a partner site mecaflux.com an application demonstrating the wright brothers work and additional information on wind tunnels.

Testing profiles in the wind tunnel are regularly used and even if mathematical and computational tools help us, the wind tunnel test phase is the final test before launch construction for many projects. The performances are recorded as lift coefficient (Cz), drag coefficient (Cd) and coefficients moment (Cm) for each incidence(attack angle) tested.

Curves Cl profiles tell us about the limits of stall :

Data Cd and Cl in function of the angle of incidence are named polar Eiffel . They give us precious information and are particularly useful for rapid analysis of the profile. The horizontal line tangent gives the maximum lift, the vertical tangent gives minimum drag, the tangent passing through the origin gives the best Cl/Cd ratio and the intersection point with the x-axis gives the zero lift.

Curves Cd Cl (left) and polar depending on incident angles and Reynolds number in the database of Heliciel software.

With Reynolds, which opens the way of comparing phenomena between different fluids and different scales by introducing the Reynolds number , we know how to use performances of a tested profile in the air to apply to water, for example. To allow the fluid and scale changes, the performance of the tested profiles are not data at test speeds, but data according to their Reynolds number. Thus Aerodynamic data bases are also valid for the hydrodynamic models and various sizes.

To have on hand aerodynamic or hydrodynamic performance data seems essential to the success of the project. We can find this data in the literature or measured in wind tunnels on models. The time and resources devoted to this research data is not negligible and limiting us in our choice of profiles. A solution to this problem was partly found by numerical calculation and authors of digital wind tunnels programs.
• Interactive data database aerodynamic and hydrodynamic profiles integrated in HELICIEL:

Performance of a NACA edited for a Reynolds number selected in ... The interactive data base of HELICIEL software

Héliciel uses data stored in a database calculated by numerical wind tunnel (more than 2000 hours of automated calculations are available , below , Free to download as data).
• The interactive data base communicates information héliciel profiles depending on the characteristics of geometry of the wing or propeller blade designed by the user. A selection is made among all the profiles of the database to provide the user with the most efficient profile (best cl / cd) that corresponds best to the blade or wing geometry .
When calculating induced velocities, Héliciel consult the database to update the coefficients of lift and drag and moment. The interactive data base Héliciel is interactive because it communicates constantly with the software. The database interface includes a system for controlling XFOIL(digital wind tunnel of Professor Mark Drela, MIT) and a profile editor that allows the user to draw a profile and to calculate automatically its performance with XFOIL.This profile can be added to the database and enrich the possibilities of profile choice in Héliciel software.

User attempting to fly a Boa having swallowed an elephant ... Who said that this profile looks like a hat?

Héliciel chooses by default in database performance profiles at CL/CD ratio optimum, to the Reynolds number calculated according to the operating conditions imposed by the user. The user can decide to choose another method of profile choice or manually select the desired profile for each element of the blade or wing. the user may also force Héliciel to use only one profile is identical for all the elements of the blade or wing.
• Search and management functions of the database can record and create database derived, to include only profiles NACA or exclude symetrics profiles...
This allows the user to select a database where he selected only the profiles that seem compatible with his project and compel HELICIEL to use only the profiles he wants!

For more information about using database Heliciel: how to use interactive database. Performance profiles being given for wings without considering the effects of leakage lift blade tip, these performances are considered performance 2D (two dimensional). Héliciel, through the calculation of induced speed and tip losses , transform these 2D in 3-dimensional data to calculate the performance of the set of elements of the propeller blade or wing.

• The interactive data base Héliciel allows the user to draw a profile and calculate its performance by automatically controlling Xfoil. Performance data profiles provided by the interactive database are from the XFOIL piloting. Analysis and correction of unconventional results is made by interactive database, then Héliciel complete the polar 360 °, by symmetry (for symmetrical profiles) and insertion of flat plates performance for the values of incidence(attack angle) above the drop lift revealing the stall.

XFOIL (Mark Drela, MIT) XFOIL is an interactive program for the design and analysis of subsonic aerodynamic isolated. It consists of a collection of menu-driven routines which perform functions such as Analysis Profile taking into account the viscosity (Reynolds number)...

• HELICIEL offers free the result of hundreds of hours of automated calculations of performance profiles. The profiles performance data provided are derived from the autopilot XFOIL by The interactive data base Héliciel. Analysis and correction of unconventional results is made by interactive database, then Héliciel complete the polar 360 °, by symmetry (for symmetrical profiles) and insertion of flat plates performance for the values of incidence(attack angle) above the drop lift revealing the stall.. These data are provided for free as it is. Thank you to report any anomalies detected.

NACA Profiles:

Profiles aero / hydro dynamics with camber:

Profils aéro/hydro dynamiques symétriques:

conventional screw series profiles:The most widely used forms of marine blades. These profiles have a maximum thickness near the center of rope, which has the effect of spreading the maximum depression of the upper surface and therefore to push back the cavitation limit. These profiles edges sharp attack also provide good performance in reverse. These databases of profiles screw series are classified according to the number and type of blade which they are intended (B3=3blades,B4=4blades...) In each database profiles are named according to their position on the radius, and area ratio. The ratio of developed area allows you to quickly assess the blade surface-working that will generate thrust.Example: Profile B3-45-02D means that this profile is a one of a 3-blade propeller, covering 45% of the surface swept by the propeller disc, located at 0.2 times the radius blade tip

• database profils_B3-screw series the classical profiles screw series for 3 marine blades. 2.02 MB (low Definition)
• database profils_B4-screw series the classical profiles screw series for 4 marine blades. 2.51 MB (low Definition)
• database profils_B5-screw series the classical profiles screw series for 5 marine blades. 2.21 MB(low Definition)
• database profils_B6-screw series the classical profiles screw series for 6 marine blades. 1.02 MB (low Definition)
• database profils_B7-screw series the classical profiles screw series for 7 marine blades. 1.50 MB (low Definition)