The 8th International Conference on Heat Transfer and Fluid Flow (HTFF’21) aims to become the leading annual conference in fields related to heat transfer and fluid flow. The goal of HTFF’21 is to gather scholars from all over the world to present advances in the relevant fields and to foster an environment conducive to exchanging ideas and information. This conference will also provide an ideal environment to develop new collaborations and meet experts on the fundamentals, applications, and products of the mentioned fields. HTFF is an acronym for Heat Transfer and Fluid Flow. Topics for HTFF’21 include, but are not limited, to the following: CFD Combustion Direct Numerical Simulations (DNS) Drying Experimental Fluid Flow and Heat Transfer Heat Exchangers, Other Heat Transfer Devices Heat Transfer Enhancement Heat Pipes Non-Newtonian Fluid Flow and Heat Transfer Phase Change Phenomena Porous Media Renewable and Non-Renewable Energies Turbomachinary