Downloading Pumpsim 2.2.0.9 from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this software available. The Pumpsim installer is commonly called Pumpsim.exe or PumpsimStart.exe etc.
We recommend checking the downloaded files with any free antivirus. The following versions: 2.2, 2.0 and 1.0 are the most frequently downloaded ones by the program users. The software lies within Photo & Graphics Tools, more precisely 3D Design. The actual developer of the software is Chasm Consulting.
From the developer:
Pumpsim is a 3D flow simulation software for pipe networks. The program allows you to design, optimize, and simulate your pump and liquid reticulation system. You can build a network of pipes, channels, pumps, tanks, valves, and sprays to simulate flows and pressures of liquids, slurries, and many other fluids. Also, the program includes a Dynamic Simulation feature that allows for the simulation of pump/pipe model behavior over a period of time.
You may want to check out more software, such as Riptide, Win4D Advance or Abalone, which might be similar to Pumpsim.