RESEARCH OF THERMAL CHARACTERISTICS OF AN IMPLANTABLE SYSTEM OF ARTIFICIAL HEART

Aim: Important problem in creation of implantable electromechanical systems of artificial heart is ensuring continuous work for a long time, under conditions of limited heat transfer. Temperature of the body of electromechanical systems should not exceed 40[degrees]C, and overheating to 42[degrees]C is admissible only in short-time modes. Methods: For the solution of this problem, numerical analysis of the thermal condition of an implantable electromechanical system of artificial heart, based on results of the solution of a stationary task of heat conductivity, was carried out by the finite elements method. Geometrical modeling of the body of electromechanical system of artificial heart was carried out in CAD-system Pro/Engineer WF 5. The solution of stationary heat transfer was approached by the finite elements method using the CAE-system by Ansys. Owing to symmetry of the design, only 1/4 of the system (including all constructive elements) was considered that influences its thermal state. The model consisted of 642263 nodes and 363231 elements. The average size of edges of finite elements is 1 mm. Modeling was carried out for various power of thermal losses 5, 8, 10 W for density of a thermal stream of 1500, 2400 and 3000 W/m super(2) respectively. Results: Images of temperature fields on the surface of the body of electromechanical system of artificial heart were obtained. Conclusions: The analysis of the thermal state at various power of thermal losses showed lack of overheating of the surface of the body of electromechanical system above critical temperature during the continuous work for a long time, and the possibility of application of the developed design as an implantable system.