A REVIEW ON RHEOLOGY OF NON-NEWTONIAN PROPERTIES OF BLOOD

Abstract

Human blood is composed of red cells, white blood cells, and platelets in a fluid called plasma that contains 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 including deformation rate dependency, viscoelasticity, yield stress, and thixotropy. The purpose of this study is mainly a review based on past work 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 the blood circulation system. ABSTRAK: Darah manusia terdiri daripada sel-sel merah, sel darah putih dan platlet dalam cecair yang dipanggil plasma, mengandungi garam organik dan mineral dan protein. Ciri-ciri sifat reologi darah ditentukan oleh sifat-sifat kombinasi ini dan interaksi antara satu sama lain. Plasma adalah pada dasarnya Newtonian cecair tetapi secara keseluruhannya darah bersifat sebagai bukan suatu cecair Newtonian yang menunjukkan tanda-tanda bukan Newtonian reologi, mengandungi pergantungan kadar ubah bentuk, kelikatkenyalan, tegasan alah dan thixotropi. Tujuan kajian ini adalah berkenaan ulasan kajian-kajian lepas berkaitan rheology darah, penentu viskositi darah, tegasan alah dan thixotropi, ukuran kelikatan darah dan pemindahan haba dalam aliran darah bagi memahami kesan bukan Newtonian dalam sistem peredaran darah.