# nanoFluidX Overview

nanoFluidX is a software to simulate single- and multi-phase flows based on the Lagrangian Particle Method "Smoothed Particle Hydrodynamics" (SPH).

The purpose of this code is to simulate complex flows that are difficult or infeasible to handle using classical CFD approaches such as Finite Volume Methods. The main advantages of SPH are the conservation of mass and momentum (linear and angular) in the absence of physical dissipation for example, due to viscous shear effects and the exact advection of the particles. As a consequence, SPH is very powerful in dealing with free-surface flows as well as multi-phase flows with complex physical phenomena such as surface-tension or interfacial transport processes. Also, using a pure particle representation allows for modeling solid dynamics and fluid-structure-interaction as well.

An important limitation of the method is a strongly increased computational complexity compared to FV-schemes, simply by the fact that a comparable virtual stencil of a SPH particle consists of up to O(100) particles in three dimensions. On the other hand, SPH is said to be "embarrassingly parallel". Computer scientists use this terminology for an algorithm in which one and the same (relatively) simple task has to be performed multiple times – which is exactly how an SPH algorithm looks like. For each individual particle the interaction forces are calculated from the neighboring particles in certain vicinity only and the position of the particles can be updated explicitly and independently of each other. #reference_cfp_g4r_k2b__fn_pvg_fpr_k2b As a consequence, SPH is well suited for GPGPU's (General Purpose Computation on Graphics Processing Unit) as their compute power can be extracted best with strongly parallelized algorithms.

Please note, nanoFluidX runs only on Linux systems with CUDA-ready GPU’s. For more information on GPU computing performance please refer to http://www.NVIDIA.com/object/tesla-servers.html.

In case of issues regarding the installation or usage of nanoFluidX please consult the Tech Support at Altair Engineering via email to hwsupport@altair.de or by phone. The contact numbers can be found on http://www.altairhyperworks.de/ClientCenterHWSupportProduct.aspx.

^{1}It is important to note that nanoFluidX follows the weakly-compressible SPH approach (WCSPH). For truly incompressible SPH the particles cannot be updated independently.