Quantcast

Search results

HomeBuiltAirplanes.com

Help Support HomeBuiltAirplanes.com:

  1. berridos

    Hi Stan, my email is sgarrido75@hotmail.com. Wish i had time to dig into the composite software...

    Hi Stan, my email is sgarrido75@hotmail.com. Wish i had time to dig into the composite software you are studying but first i am struggling with openfoam. It looks extremly interesting and maybe for cristmas i share a license with someone. Regards Sebastian
  2. berridos

    Composite wing ribs

    The foam core absorbs lots of epoxy in infusion processes. Would be very interesting to evaluate the physical properties of wrinkled/zigzag ribs. I mean, like a cardboard but without the inner and outer layer. Such a rib could be infused nicely in one step and without core.
  3. berridos

    XLFR5 Reverse Engeneering Verhees Delta

    Thanks Brandon, i started at the center section. Will correct the exercise and add also the ventral fin . However got the feeling that the later jump to open foam will be unavoidable in order to tailor a better spanwise lift distributions. Verhees told me he used a modified 63020. Did you do...
  4. berridos

    XLFR5 Reverse Engeneering Verhees Delta

    So the hypothesis that the rudder is producing pitch up is wrong? How otherwise would the plane be capable of level flight with a simetrical airfoil?
  5. berridos

    XLFR5 Reverse Engeneering Verhees Delta

    I already bought the real sized plans, The airfoil down on the left shows a 1,5º reflex. According to xflr5 thats too much in cruise.
  6. berridos

    Wainfan Facetmobile inspired drone delivery

    Looking at it for the tenth time i really got the feeling that the delivery/drop off forward speed looks slow.
  7. berridos

    XLFR5 Reverse Engeneering Verhees Delta

    Hi everybody I am having a hard time understanding the verhees delta in xflr5. Basic parameters of the original: CoG between 1270 and 1390 cm Cruise speed 220kmh = 62 ms Nowhere is stated the reflex used in cruise, but on the main plans, i measured on an uncommented picture, an up reflex of...
  8. berridos

    Raptor Composite Aircraft

    I am really having a hard time believing (uneducated guess) that the turboencabulator doesnt produce tons of interference drag between the canard and the main wing and other turbulent drag creatures i ignore the name of, compared to a reflexed airfoil. Would be lovely to see some wind tunnel...
  9. berridos

    Raptor Composite Aircraft

    How many fixes are tolerable for a supposedly top product? They all detract from performance. At the end it will resemble a Formula 1 car.
  10. berridos

    Raptor Composite Aircraft

    Some suspect that the plane showed dutch roll problems. If thats the case, the end of this saga would be an anticlimax, because for such an aero problem there is no solution at this stage. Two more hops confirming this and to the junkyard. Hope carbon at weight can be recyled somehow.
  11. berridos

    Suitable airfoil large thickness, high RE

    I guess those very high CL numbers are related to the huge RE in this psecial case. Always understood that the longer the chord the more stable the laminar flow and this case seems to guarantee extreme laminar flow. Should cruise CL be set at 0,3 for a delta or should i take additional...
  12. berridos

    Suitable airfoil large thickness, high RE

    I suffer strong sleep deprivation in my endless search for the appropriate root profile for my double delta vortex project. Requirements are RE13.000.000 and pitch neutrality. After several days getting fond of XLFR5 i have to conclued that this software smells a lot like a black blox, at least...
  13. berridos

    Raptor Composite Aircraft

    The only innovative thing about this plane is that it is a flying livingroom with nice curtains and sofas. Besides that, he has piled up a dozen unproven gadgets and poorly adapted solutions that just give a sense of innovation.
  14. berridos

    Raptor Composite Aircraft

    Wasnt it jeff kerlo the one doing the composite work? He is supposed to be a well reputed composite expert. How is it that his eyesballs didnt became white when laying up the sheets for the keel. Maybe he thought he was laminating an U-Boot?
  15. berridos

    Suitable airfoil large thickness, high RE

    Wouldnt such a stall be prevented with an all moving tip elevon like the one shown in the rc model?
  16. berridos

    Suitable airfoil large thickness, high RE

    In the first approach you suggest (with matching LE and TE points) i would define an intersection point (somewhere behind the thickest section station) and move the points before up and the points behind down, but according to which function? Thank you very much for the hints.
  17. berridos

    Suitable airfoil large thickness, high RE

    In order to reflex an airfoil I wonder if it is ortodox to preserve the points from the camberline up to the station from which i want to bend upwards the camberline and from that station on, propose for example 2 points (guess more points are required) moved upward and fit a polynomial with...
  18. berridos

    Suitable airfoil large thickness, high RE

    Thank you very much. Reflexing foils is a research field in itself. Yesterday i imported foils into solidworks and i am wondering really if the exercise wouldnt be much more straightforward if i modify the camberline in excel applying functions. I need to learn the effects of starting the reflex...
  19. berridos

    Suitable airfoil large thickness, high RE

    Is there any paper that explains how to reflex an airfoil in a reasonable manner, to eliminate pitching moment? The 654221 has a tiny downward kink at the te.
Top