Is there an analytical solution to this equation?

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SUMMARY

The discussion centers on the analytical solution of a differential equation derived from the rocket equation with air resistance, specifically using the drag model for a Reynolds number (Re) around 15000. The second drag model, F_drag=1/2*A*rho*CD*v^2, is identified as the most appropriate for this scenario. Participants conclude that there is no closed-form solution unless specific parameters such as mass loss rate and exhaust velocity are finely tuned. Additionally, testing simplified equations with tools like Wolfram Alpha is suggested for further exploration.

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MigMRF
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So I've derived the rocket equation in empty space and with constant gravity. Now I am interested in adding air resistance. I'm aware that there are 2 different models as if 0<Re<1 then F_drag=k*v and if 1000<Re<30000 then F_drag=1/2*A*rho*CD*v^2. And for my purpose the second model is most fitting (my Re is around 15000. So I've come up with a differentialequation and was wondering if there actually is a solution. Here is my equation:
1576411179923.png

So first of all, is the equation correct. I'm kind of new to differential equations.
And if it's correct then is there an analytical solution.

I'd like some help on this one :D
 
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There's no closed form solution for that equation unless you find a way to set the mass loss rate, exhaust velocity and air resistance parameters just right to "accidentally" make this have a simple solution.

You can test this by putting some simplified equations of the same type, e.g.

##\displaystyle (1-at)\frac{d^2 x}{dt^2} =b-\left(\frac{dx}{dt}\right)^2##

to Wolfram Alpha for it to try to solve them.
 

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