Free tools usually focus strictly on thermal design, omitting mechanical calculations like flange thickness, shell wall thickness, and welding specs according to ASME Section VIII.

HTX is a dedicated, lightweight freeware tool specifically engineered for the preliminary thermal design of shell and tube heat exchangers. Quick sizing and educational purposes. Key Features: Step-by-step input wizard. Handles single-phase fluids. Calculates log mean temperature difference (LMTD). Estimates required surface area and tube counts. Availability: Free executable download for Windows. 3. OpenFOAM (Advanced CFD Analysis)

Navigate to a trusted repository. (Avoid "download.com" type aggregators filled with adware). Unzip the folder. No installation is usually required—it runs as a standalone .exe .

Click "Design Mode." The software will iterate to find the required tube length. If the pressure drop exceeds 10 psi, increase the baffle spacing.