Time of Flight Diffraction 2D - CAD


Maximum acoustic pressure field

Model Description

TOFD is a flexible technique, which relies on a range of mode converted signals to be effective. OnScale combines the capability of accurately simulating mode conversion in arbitrary geometries, with the speed to run large batches of TOFD models, making it an ideal tool for improving inspection setup.

Time of Flight Diffraction finds use in various industries who utilize NDT, from Oil and Gas to power generation. Originally developed for crack sizing, TOFD can also be used for everything from routine screening to corrosion mapping.

Here is a 2D CAD model to simulate a Time of Flight Diffraction (TOFD) inspection of a steel block containing a defect.


Basic Model Schematic

Parametric Variables

The base CAD model was created in Onshape and allows the following design variables to be adjusted. By default defect depth and defect height are added as configuration variables for quick access through the Configuration Panel in Onshape.

Parametric Variable Description Default Value
defect_dpth Depth of defect 7 mm
defect_hgt Height of defect 4 mm
defect_wdth Width of thickness 0.2 mm
plate_thk Plate thickness 15 mm


Here are a list of the types of outputs to expect from this model.

  • Acoustic pressure at nodes along receiver
  • Maximum acoustic pressure for beam analysis


Post Processor Outputs

Runtime Statistics

Model size 561816 elements
Solve Time  11 s (4 CPU)
Core Hours 0.012
Memory Usage 38 MB
Recommended CPU Configuration 4 CPU

CAD Project File

The following input files are required to run this model, click here to download the input files:

Download: Time of Flight Diffraction 2D Project

The base CAD model is publicly available to view and copy through Onshape:

Model: Time of Flight Diffraction 2D Onshape