Propeller graphs 0 Thrust issue

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Hemant Sriram

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Oct 18, 2021, 6:25:02 AM10/18/21
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Hi Emilio,

I am so sorry to bother you with another issue I am facing. I have set up a new configuration in SUAVE for analyses and I am running into an error where the lift coefficient generated is very small in the order of 0.03 and the Propeller coefficient graph provides a 0 thrust plot and negative tip Mach, and Cp. I am not sure where I can go to solve the error. I have already tried to change the motor, prop and battery size to get better results but haven't got any better results.

Here is the plot as I am getting it currently
Propeller.pngeMotor_Prop_Propulsor.png  

Where can I find the iterative loop that calculates the thrust for every iteration and what does that loop call and pass trough? Is the thrust being calculated for each time step?

I am not sure what I need to look at to solve this, as the code is very sensitive as far as I have seen and thus a few changes affects a lot of things in the code.

Hope to hear from you soon.
Hemant Sriram

ebot...@gmail.com

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Oct 23, 2021, 2:23:44 AM10/23/21
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Hi,
The propeller's thrust is calculated here. The propeller has its iteration which is then wrapped in the mission solver. So there's multiple layers of iteration.

If I recall correctly, you're working with a solar UAV. Those are very sensitive (same as real life). I usually see plots like that when descending rapidly. But that looks like a cruise segment. I don't have enough information to say what is wrong here.

-Emilio

Hemant Sriram

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Oct 23, 2021, 2:41:36 AM10/23/21
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Hi,

Thanks for the response, I was able to figure out the issue and by changing a few values around, the graphs make a lot more sense. Yes, the outputs are very sensitive to the provided inputs. It's a very delicate process in designing using the solar propulsor file.

Regards
Hemant
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