Abstract In this article turbulent flow of water through a horizontal pipe, considering sediment suspension under steady state is analyzed, inhomogeneity of temperature and effects of buoyancy and viscous dissipation have been taken into account. The effect of buoyancy forces has been analyzed using Grashof number (Gr), while that of viscous heating has been analyzed through the Eckert number (Ec). The Navier–Stokes, energy, and continuity equations in dimensionless form were numerically solved using the collocation method through MATLAB and the Boussinesq approximation was utilized to address buoyancy through temperature only. It is found that the Inhomogeneous ambient temperature of hot and cold fluid behaves as a potential source of sound, Nusselt number and suction, Grashof number increases the buoyancy induced flow structures become more upgraded resulting stronger velocity gradients with enhanced mixing, similarly the effects of viscous dissipation are higher in localized temperature increase. Flattening of the velocity profile and less radial variation led to a more uniform axial distribution of velocity compared to that of the laminar flow. The present results show the ability of the collocation technique in modeling complex thermally affected turbulent flows and suggest guidelines for optimizing pipe flow systems affected by buoyancy and viscous heating.