This is a simple phased array simulator running on GPUs. Just open the rtpas.html in your browser to run it. You can adjust parameters of the wave, simulation scales, etc. It requires WebGL ability in browser. Don't worry, now all browsers support it.
An interesting point is, phased array can not only control the beam direction, but also focus the energy into one point. This can be simulated by check the "Need Focus". You may need more emitters to get a better result in this mode.
Phased Array Simulator is distributed under the terms of MIT License. See LICENSE for details.