Hi! I am modelling particle acceleration in an abrasive-particle-in-water-slurry (nozzle design for water jet cutting). I have chosen pressure inlet and pressure outlet and a surface particle injection. My problem is: When the pressure difference between inlet and outlet ist higher than approx. 2 or 3 MPa, I get a Floating Point Exception (underflow). I need at least 70 MPa. Can anyone help, please? (Sorry if this is trivial, but I am quite a greenhorn in CFD.) Best regards, Alex.

Hi Alex, I found floating point exception exceptionally many times !! In this forum, this issue has been addressed many times. I normally try the followings: a) using 2ddp/3ddp or otherway around (if you used double precision b4, use single precision) b) create the mesh again c) change the time steps.. change to model for few iterations..d) increase the flow/pressure difference gradually..

This may not help, but you never know !! DC

[zullah]

Hi there,

Iam a Master student at Korea Maritime Uni. Iam new to ANSYS CFX, but have managed to learn a lot till know. I have a similar problem with my calculation. Its a Multi-quasi flow cal. "Floating point exception: Overflow" always arises if i use a smaller timestep but with a bigger timestep it works fine. But i have to use small timestep to calculation torque generated by the wave turbine more accurately.

Please need help.Thank you in advanvce.