Recent content by Ax_xiom

Hello, it's been a while, and I've decided to revisit this topic. I have a quick question: when dealing with partial derivatives, is it fine to treat them as ordinary derivatives if the values depend only on one variable? I'm trying to derive the expressions in the paper from the ones in the...

Ok, is ##t_0## or ##t_d## the column I should be looking at for this?

So plot overpressure against mach number?

Isn't that what I did when I got the result I'm currently testing? I took the result for ##\frac{dz}{dt}## and changed it to an expression of the mach number, then used that expression to calculate the pressure (and overpressure)

Do you mean compare overpressure to the mach number of the shockwave?

Interesting. For smaller distances my model aligns with the data fairly well (although the trend seems to be slightly less than cubic) but for larger distances the pressure values seem to follow a completely different relationship entirely.

Alright, thanks!

Do mach reflections affect the overpressure that much? Even when the explosion is on the ground? I reasoned that the effects would only be some sort of scaling factor as the solution that Diaz came up with was able to model surface bursts by dividing the calculated yield by 1.8 to account for...

What Nukemap does is that it takes Glasstone and Dolan's data on nuclear weapons and interpolates between them to allow Nukemap to simulate airbursts. More detail about nukemap can be found here. Also isn't the STvN solution for the position of a shockwave? How would you use it for the...

Yeah, I've done the same for distance and the equation also disagrees: The overpressure seems to be decreasing similarly to the inverse square law but my model predicts a cubic decrease. It does, that's why it can also model airbursts aswell

This one by Alex Wellerstein. The dimensional analysis makes sense but plotting yield and overpressure on a graph shows that it isn't linear: Taking the logarithm of both sides and checking the gradient of the line makes the non-linear trend of the line even more clear: It looks more like a...

I did it with overpressure and I'm getting some odd results: dR/dt transforms with the chain rule like this: $$\frac{dR}{dt} = \frac{dR}{dz}\frac{dz}{d\tau}\frac{d\tau}{dt}$$ And our variables are these: $$ \begin{align*} R_{0}z &= R \\ \tau &= \frac{a_{0}t}{R_{0}} \end{align*} $$ So their final...

I wonder if it's possible to use these equations to calculate the air velocity and pressure of a blast wave at a given distance with a given energy. ##M_{s} = a_{0}^{-1}(\frac{dR}{dt})## and we already have an expression for ##\frac{dz}{d\tau}## which is the scaled distance over the scaled time.

Ok thanks, I'll see what I can do here

I don't think he explains in the video but I think it's the speed of sound in the medium based on what he says about the final equation. He did mention that he would use these equations: And the Rankine-Hugonoit boundary conditions to solve the equations so maybe that is what he did there.