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International audienceContext. With the progress of observational constraints on stellarrotation and on the angular velocity profile in stars, it is necessary to understand howangular momentum is transported in stellar interiors during their whole evolution. In thiscontext, more highly refined dynamical stellar evolution models have been built that takeinto account transport mechanisms.Aims. Internal gravity waves (IGWs) excited by convective regionsconstitute an efficient transport mechanism over long distances in stellar radiationzones. They are one of the mechanisms that are suspected of being responsible for thequasi-flat rotation profile of the solar radiative region up to0.2 R⊙. Therefore, we include them in our detailed analysisstarted in Paper I of the main physical processes responsible for the transport of angularmomentum and chemical species in stellar radiation zones. Here, we focus on the completeinteraction between differential rotation, meridional circulation, shear-inducedturbulence, and IGWs during the main sequence.Methods. We improved the diagnosis tools designed in Paper I to unravelangular momentum transport and chemical mixing in rotating stars by taking into accountIGWs. The star’s secular hydrodynamics is treated using projection on axisymmetricspherical harmonics and appropriate horizontal averages that allow the problem to bereduced to one dimension while preserving the non-diffusive character of angular momentumtransport by the meridional circulation and IGWs. Wave excitation by convective zones iscomputed at each time-step of the evolution track. We choose here to analyse the evolutionof a 1.1 M⊙, Z⊙ star in which IGWsare known to be efficient.Results. We quantify the relative importance of the physical mechanismsthat sustain meridional currents and that drive the transport of angular momentum, heat,and chemicals when IGWs are taken into account. First, angular momentum extraction,Reynolds stresses caused by IGWs, and viscous stresses sustain a large-scalemulti-cellular meridional circulation. This circulation in turn advects entropy, whichgenerates temperature fluctuations and a new rotation profile because of thermal wind.Conclusions. We have refined our diagnosis of secular transportprocesses in stellar interiors. We confirm that meridional circulation is sustained byapplied torques, internal stresses, and structural readjustments, rather than by thermalimbalance, and we detail the impact of IGWs. These large-scale flows then modify thethermal structure of stars, their internal rotation profile, and their chemicalstratification. The tools we developed in Paper I and generalised for the present analysiswill be used in the near future to study secular hydrodynamics of rotating stars takinginto account IGWs in the whole Hertzsprung-Russell diagram

Diagnoses to unravel secular hydrodynamical processes in rotating main sequence stars