Human blood is composed of red cells, white blood cells and platelets in a fluid called plasma that content of organic and mineral salts and protein. The rheological characteristics of blood are determined by the properties of these combinations and their interaction with each other. The plasma is essentially a Newtonian fluid but the blood as a whole behaves as a non-Newtonian fluid showing all signs of non-Newtonian rheology which includes deformation rate dependency, viscoelasticity, yield stress and thixotropy. The purpose of this study is mainly a review based on past works on blood rheology, determinants of blood viscosity, yield stress, thixotropy, blood viscosity measurement and heat transfer in blood flow to better understand the non-Newtonian effect in blood circulation system.
