Hybrid (numerical-physical) circulatory models: Description and possible applications

Circulatory models are used for several applications ranging from research, to education and training. They are based on different structures that are essentially numerical or hydraulic. Both structures present advantages and disadvantages which suggested developing a new class of circulatory models, defined as hybrid: hybrid circulatory models permit to merge numerical and physical models. This solution reduces the costs, enhances the flexibility and opens the way to many applications. This paper presents a prototype consisting of a hydraulic model of systemic arterial tree connected to a lumped parameters numerical model of the circulation developed In Lab VIEW(TM). The behavior of the model was verified reproducing two circulatory conditions, physiological and pathological. The latter was assisted by means of an intra-aortic balloon pump. The results show that hybrid modeling permits to build complex networks merging models based on different structures. The hybrid system Is able to react to events occurring Indifferently In any of the structures forming It.