International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 04 Issue: 08 | Aug -2017 www.irjet.net p-ISSN: 2395-0072 © 2017, IRJET | Impact Factor value: 5.181 | ISO 9001:2008 Certified Journal | Page 1856 Effect of Magnetic Field on Flow Behaviour of Blood through A Modelled Atherosclerotic Artery Mr. Samuel Debberma 1 and Mr. Shashank Srivastava 2 1 M.Tech Scholar, Department of Mechanical Engineering, NIT Silchar, India,Hno.66 By Lane3,Ujan Abhoynagar Agartala ,Tripura West India 2 B.Tech 2012 Batch ,Department of Mechanical Engineering,Beant College of Engineering and Technology Gurdaspur Punjab India, H.no1 Puspa Niketan Kali Bari marg Cantt. Road Lucknow UP 226001 ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - In this theoretical study a mathematical model is developed to study the effect of stenosis on flow behaviour of the streaming blood through an atherosclerotic artery in the presence of magnetic field. The non-Newtonian character of blood is taken into account using Casson fluid model of the blood. The coupled differential equations governing the MHD flow of blood are solved by a combined use of analytical and numerical techniques in the appropriate boundary conditions. The geometry of the asymmetric shape of the stenosis assumed to be manifested in the arterial segment is given due consideration in the analysis. An extensive quantitative analysis is performed through large scale numerical computations of the measurable flow variables having more physiological significance by developing computer codes. Some important observations having medical interest in the flow of the blood in the stenosed arteries are obtained. Key Words: Stenosis; Casson fluid; Magnetic field; Shear stress; Slip velocity 1. INTRODUCTION Stenosis , (borrowed from Ancient Greek στένωσιςȌ is defined as the abnormal narrowing of body passage tube or orifice that cause serious circulatory disorders leading to cardiac failure. While the exact mechanism of the formation of stenosis in a conclusive manner is unclear from the standpoint of anatomy, physiology and pathology, the abnormal deposition of various substances like cholesterol, fat on the endothelium of the arterial wall and proliferation of connected tissues accelerate the growth of the disease. Once the constriction in the artery develops cholesterol, fat and other substances build up in the inner lining of the artery and this natural process is called 1.1 Carotid Circulatory Disorders: It generally disturbs the normal blood flow leading to malfunctioning of the hemodynamic system and the cardiovascular system. Carotid Artery Stenosis is a major risk factor for Ischemic Stroke (most common form of stroke usually caused by blood clot plugging in artery.) The fact that the hemodynamic factors play a commendable role in the genesis and growth of the disease has attracted many researchers to explore modern approach and sophisticated mathematical models for investigation on flow through stenosed arteries. To illuminate the effects of stenosis present in the arterial lumen intensive experimental and theoretical researches have been carried out worldwide for both normal and stenotic arteries. In most of the investigations relevant to the domain under discussion, the Newtonian model of blood (single phase homogeneous viscous fluid) was accepted. This model of blood is acceptable for high shear rate in case of flow through narrow arteries of diameter ζ ͳͲͲͲµm. Experimental observations reveal that blood being predominantly a suspension of erythrocytes in plasma exhibits remarkable non-Newtonian behaviour when it flows through narrow arteries, at low shear rate particularly, in diseased state when clotting effects in small arteries are present. A more comprehensive study on the diagnosis, prevention and treatment of stenosis related diseases suggest that an accurate description of blood flow requires consideration of erythrocytes (red cells) as discrete particles in small arteries. In view of their observations it is preferable to represent the flow of blood in narrow arteries by a non-Newtonian fluid. H-B fluid model and Casson fluid models are generally used in the theoretical investigation of blood through narrow arteries. Due to the presence of the substances like proteins, fibrinogens and globulin in an aqueous base plasma human red blood cells can form a chain like structure, known as aggregates or rouleaux. As the rouleaux behaves like a plastic solid then there exists a yield stress that can be identified with the constant yield stress in Casson’s fluid. So, many investigations have reported that blood may be better described by Casson fluid model at low shear rates as blood possesses a finite non-zero yield stress. Also blood may be considered as a suspension of magnetic particles (red cells) in non-magnetic plasma due to the presence of hemoglobin (an iron compound) in red cells. Many researchers have investigated the effect of magnetic field on blood flow treating blood as an electrically conductive fluid. The conductive flow in the presence of a magnetic field induces voltage and current leading to a decrease in flow. The importance of heat transfer on artery