OpenVSP dimensioning
Harold Nikoue
I have just started using openVSP to model an airplane from a three-
view drawing.
Although I don't have any problem editing the dimensions of the
fuselage, I cannot use my own dimensions for the wind and the
stabilizers.
I have noticed that the program automatically adjust the Aspect Ratio,
probably according to a generating table of wing configuration.
Would it there be a way to override this predefined Aspect ratio,
configuration,and freely build the wing?
Harold
Rob McDonald
Welcome to VSP.
The wing-editing window has six tabs across the top -- Gen, XForm,
Plan, Sect, Dihed, Foil. They are each used to control a certain
subset of the Wing's prameters.
For most wing planform editing, you want to work from the 'Sect' tab.
The top half of the Sect tab is used to add/remove wing sections, and
to make sure you're editing the section you want. You can model
many wings with just one or two sections. A wing section is a good
way to represent a break in the wing planform. To start with, I
suggest you delete the outboard sections and just play around with a
single section wing.
The bottom of the Sect tab is where all the real action happens.
There, you will find all the usual parameters for defining a wing.
The most important six are grouped together. Aspect Ratio, Taper
Ratio, Area, Span, Tip Chord, and Root Chord. If you've worked with
these non-dimensional quantities before, you will know that you can
specify a wing with different subsets of these variables.
VSP lets you pick what three 'drivers' you want to work with. So, if
you're working form a 3-view drawing, you may already know for example
the span, root chord, and tip chord.
So, pick the down-arrow by 'Driver:' and pick from the seven choices.
When you do, the variables you have chosen are 'active' and the other
three are greyed out. Those variables will be calculated based on the
'driver' group.
You may want to check out the tutorial videos linked form the
openvsp.org web site. Tutorial #3 works with wings starting at 2:30.
You may want to skip to 4:15 in that tutorial.
Let us know if you're still having trouble,
Rob
Harold Nikoue
I broke the wing into an inboard and outboard region, and was able to
obtain much better results.
Thank you Rob