Hello dear community,

I am still very new to Abaqus. The topic I am currently working on is a chamber weight optimization where 200bar is acting. First, I have to find the critical areas in the chamber.

When I first assumed the pressure load to be uniformly distributed and constant throughout the chamber, I had a max Mises stress of 4.5*10^2 MPa (= 450MPa). However, to make the stress more accurate and realistic, I converted the constant pressure into a pressure curve using the Analytic Field function. The pressure starts at 200bar and ends at 8bar at the end of the nozzle. But the result was then about 7.5*10^3 MPa (=7500MPa). I checked the functions and the units and they look fine. I then tried using a constant, uniformly distributed pressure at 200bar throughout the chamber described by an analytical field function, but the order of the results was the same (*10^3). This means that the load is the same (200 bar throughout), but applied once uniformly distributed without a function and once with an analytical field function (0*X + 20MPa), which is just a line in a coordinate system. Then I noticed that I get different results because I use the analytical field function at all. My question: why do I get a different result? What does the analytic field function do to make the result larger than without it? Can I use a different toolset to describe a pressure curve?

Thanks in advance!