Numerical method toward fast and accurate calculation of dilute quantum gas using Uehling-Uhlenbeck model equation

TL;DR

This paper develops a fast and accurate numerical method using DSMC to solve the Uehling-Uhlenbeck model for dilute quantum gases, enabling efficient computation of gas dynamics and properties.

Contribution

It introduces a DSMC-based approach to solve the U-U model equation, improving computational speed and accuracy for dilute quantum gas simulations.

Findings

Accurate thermalization achieved with fewer sample particles.

Viscosity coefficient of Bose gas calculated reliably.

Shock layer analysis around a cylinder demonstrated.

Abstract

The numerical method toward the fast and accurate calculation of the dilute quantum gas is studied by proposing the Uehing-Uhlenbeck (U-U) model equation. In particular, the direct simulation Monte Carlo (DSMC) method is used to solve the U-U model equation. The DSMC analysis of the U-U model equation surely enables us to obtain the accurate thermalization using a small number of sample particles and calculate the dilute quantum gas dynamics in practical time. Finally, the availability of the DSMC analysis of the U-U model equation toward the fast and accurate calculation of the dilute quantum gas is confirmed by calculating the viscosity coefficient of the Bose gas on the basis of Green-Kubo expression or shock layer of the dilute Bose gas around a circular cylinder