AeroPerformanceMap

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I would like to suggest a change to the flight conditions section in the 
aeroPerformanceMap node.

The change would be adding the choice between reynolds and altitude. 
(see attachment)

In fact, I was trying to find a solution for the output of Tornado. 
Indeed, Tornado does not support the input of a reynolds number and uses an 
altitude input. This is a little annoying because there's no valid way of 
writing the output into CPACS. However, through the standard atmosphere, the 
input of (mach, altitude) pairs is equivalent to (mach,
reynolds) pairs. So remplacing reynolds by altitude seems legitimate to me, but 
of course the resulting conditions would not be the same.

I don't like it when specifications change, but this way, Tornado could 
actually produce a valid output CPACS. And the proposal is backwards 
compatible...

<xsd:choice>
    <xsd:element
        name="reynoldsNumber"
        type="stringVectorBaseType">
        <xsd:annotation>
            <xsd:documentation>Reynolds Number</xsd:documentation>
        </xsd:annotation>
    </xsd:element>
    <xsd:element
        name="altitude"
        type="stringVectorBaseType">
        <xsd:annotation>
            <xsd:documentation>Altitude</xsd:documentation>
        </xsd:annotation>
    </xsd:element>
</xsd:choice>

Original issue reported on code.google.com by daniel.b...@googlemail.com on 31 Aug 2012 at 7:27

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Original comment by daniel.b...@googlemail.com on 9 Oct 2012 at 7:01

• Added labels: milestone-CPACS2.01

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[deleted comment]

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New version of altitude-to-Reynolds converted map (previous one involved some 
extrapolation). In annotation the data point's altitude in km; chord length is 
4.19 m.

Original comment by brsverv...@gmail.com on 15 Oct 2012 at 2:16

Attachments:

• re_from_alt.png

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We now do have several arguments for the discussion of altitude vs. 
reynoldsnumber as the second parameter for the performance map in combination 
with the mach number:

With the altitude the range of the values is certainly smaller. The 
reynoldsnumbers need to be scaled from approx 2mio to 80mio to cover a complete 
jet aircraft flight regime. 

With the reynoldsnumber it might be a lot easier to work in different 
atmospheres (ISA+15, ISA+30). This might become important as soon as we start 
working on detailed starting and landing simulations. If these temerature 
variations need to be included from the altitude, there might be a lot of 
conversions. 

Still no decision, but at least we might feel smarter

Original comment by daniel.b...@googlemail.com on 24 Oct 2012 at 7:43

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For CPACS 2.01 the aeroPerformancMap will stick to the Reynoldsnumber. For 
takeoff filed length calculations at different ambient settings this seems to 
be reasonable. 

Original comment by daniel.b...@googlemail.com on 30 Oct 2012 at 2:18

• Added labels: milestone-CPACS2.0
• Removed labels: milestone-CPACS2.01

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Original comment by daniel.b...@googlemail.com on 27 May 2013 at 8:02

• Changed state: Done