Direct simulation Monte Carlo

Direct simulation Monte Carlo (DSMC) method uses probabilistic <a href="/facts/Monte_Carlo_method/AkHjY7jc">Monte Carlo</a> <a href="/facts/Simulation/Q4QJV1oI">simulation</a> to solve the <a href="/facts/Boltzmann_equation/6oRPrApT">Boltzmann equation</a> for finite <a href="/facts/Knudsen_number/rW2GxklD">Knudsen number</a> <a href="/facts/Fluid/tMQ46Tmz">fluid</a> flows.
The DSMC method was proposed by Graeme Bird, emeritus professor of aeronautics, University of Sydney. DSMC is a numerical method for modeling rarefied gas flows, in which the <a href="/facts/Mean_free_path/6M7eofRq">mean free path</a> of a molecule is of the same order (or greater) than a representative physical length scale (i.e. the <a href="/facts/Knudsen_number/rW2GxklD">Knudsen number</a> Kn is greater than 1). In supersonic and hypersonic flows rarefaction is characterized by Tsien's parameter, which is equivalent to the product of Knudsen number and Mach number (KnM) or M
 
 
 
 
 
 
 2
 
 
 
 
 {\displaystyle ^{2}}
 
/Re, where Re is the Reynolds number. In these rarefied flows, the <a href="/facts/Navier-Stokes_equations/48pQugEa">Navier-Stokes equations</a> can be inaccurate. The DSMC method has been extended to model continuum flows (Kn < 1) and the results can be compared with Navier Stokes solutions.
The DSMC method models fluid flows using probabilistic simulation <a href="/facts/Molecule/N9ljSfFq">molecules</a> to solve the <a href="/facts/Boltzmann_equation/6oRPrApT">Boltzmann equation</a>. Molecules are moved through a simulation of physical space in a realistic manner that is directly coupled to physical time such that unsteady flow characteristics can be modeled. Intermolecular collisions and molecule-surface collisions are calculated using probabilistic, <a href="/facts/Phenomenological_model/z8vypElI">phenomenological models</a>. Common molecular models include the hard sphere model, the variable hard sphere (VHS) model, and the variable soft sphere (VSS) model. Various collision models are presented in. 
Currently, the DSMC method has been applied to the solution of flows ranging from estimation of the <a href="/facts/Space_Shuttle/7BoyetEv">Space Shuttle</a> re-entry aerodynamics to the modeling of <a href="/facts/Microelectromechanical_systems/TkhEzDpm">microelectromechanical systems</a> (MEMS).

Direct simulation Monte Carlo open-in-new

Direct simulation Monte Carlo