@misc{10481/70217, year = {2021}, month = {1}, url = {http://hdl.handle.net/10481/70217}, abstract = {In this paper, we present the hydrodynamic limit of a multiscale system describing the dynamics of two populations of agents with alignment interactions and the effect of an internal variable. It consists of a kinetic equation coupled with an Euler-type equation inspired by the thermomechanical Cucker–Smale (TCS) model. We propose a novel drag force for the fluid-particle interaction reminiscent of Stokes’ law. Whilst the macroscopic species is regarded as a self-organized background fluid that affects the kinetic species, the latter is assumed sparse and does not affect the macroscopic dynamics. We propose two hyperbolic scalings, in terms of a strong and weak relaxation regime of the internal variable towards the background population. Under each regime, we prove the rigorous hydrodynamic limit towards a coupled system composed of two Euler-type equations. Inertial effects of momentum and internal variable in the kinetic species disappear for strong relaxation, whereas a nontrivial dynamics for the internal variable appears for weak relaxation. Our analysis covers both the case of Lipschitz and weakly singular influence functions.}, organization = {European Research Council (ERC) 639638}, organization = {MECD (Spain) FPU14/06304}, organization = {MINECO-Feder (Spain) RTI2018-098850-B-I00}, organization = {Junta de Andalucia European Commission PY18-RT-2422 A-FQM-311-UGR18}, organization = {Basic Science Research Program through the National Research Foundation of Korea (NRF) - Ministry of Science and ICT NRF-2020R1A4A3079066}, publisher = {World Scientific}, keywords = {Flocking}, keywords = {Hydrodynamic limit}, keywords = {Kinetic model}, keywords = {Multiscale model}, keywords = {Thermomechanical Cucker-Smale model}, keywords = {Internal variable}, keywords = {Singular weights}, title = {Hydrodynamic limit of a coupled Cucker-Smale system with strong and weak internal variable relaxation}, doi = {10.1142/S0218202521400042}, author = {Kim, Jeongho and Poyato Sánchez, Jesús David and Soler Vizcaino, Juan Segundo}, }