Simulator · v2.0
Ultrasound and Doppler Physics - An Interactive Course
Thirty-four steps from sonar to contrast echo, with every simulation computed live: wave propagation, beam formation, artifacts, spectral and colour Doppler, and the measurement equations behind filling pressures.
Echo physics is usually taught as equations to be memorised before the machine is allowed to be touched, and most of it evaporates by the time it matters. This runs the equations as simulations instead: change the frequency and watch the penetration change, move the sample volume and watch the spectrum alias, narrow the orifice and watch the velocity climb.
Thirty-four steps in order, in eleven parts, from a sonar transducer in 1914 through to microbubble contrast. The wave solver is real, not an animation of a wave, so the artifacts that appear are the ones the physics produces.
Using it in a teaching session
The Doppler section repays the most time. Angle dependence is understood by everyone in the abstract and misapplied constantly in practice, and watching the measured velocity fall away as the angle opens fixes it faster than the cosine rule ever does.
Aliasing is the other one. Trainees learn the Nyquist limit as a number and then meet a colour map they cannot interpret. Moving the sample volume deeper until the spectrum wraps makes the relationship concrete.
For the measurement sections, work an example the room already knows. Continuity for aortic stenosis, PISA for mitral regurgitation, E over e-prime for filling pressures. Seeing the equation respond to a change in one variable is what makes it stick.
There are ten questions at the end for checking retention.
What the model simplifies
Tissue is modelled as a small number of uniform layers, the beam geometry is idealised, and every trace is computed rather than acquired. It teaches the physics that underlies the machine, not the appearance of any particular scanner, and it is no substitute for supervised scanning.