Lecture 18.Circulation

Lecture 18.Circulation - LS2 Design of the circulatory...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
LS2 Design of the circulatory system Prof. George V. Lauder Office Hours: Friday 2-3+ (after class) and by appointment. Assigned Reading for this lecture: Custom text, pp. 494 – 498 and 518-546 (green page #s)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Lecture outline Basic design of the circulatory system Pipe flow design: Poiseuille equation Manifold design Structural organization of vessels capillaries, arteries, veins Regulation of blood flow: blood vessels are “smart pipes” that respond to local and extrinsic factors Comparative design of circulatory systems: fish vs mammals Partially divided ventricle in lungfishes and characters shared with tetrapods The amazing lungfish cardiovascular system which changes with water and air respiration
Background image of page 2
Vogel, S. (1992). Vital Circuits. New York: Oxford Univ. Press. Vogel, S. (1994). Nature's pumps. Amer. Sci. 82, 464-471. Some readings for those interested:
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
The heart is the pump that propels the blood through the systemic and pulmonary circuits. Red color indicates blood that is fully oxygenated. Blue color represents blood that is only partially oxygenated. Basic design of the circulatory system Be sure that you can trace the path of blood in adult and fetal circulations.
Background image of page 4
Though pressure is higher in the lower “tube,” the flow rates in the pair of tubes is identical because they both have the same pressure difference (90 mm Hg) between points P 1 and P 2 . Basic design of the circulatory system: pipe flow
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Pipe flow (‘laminar flow’ - fluid moves in parallel fashion) Flow (Q) velocity P 1 > P 2 P 1 P 2 Basic design of the circulatory system: pipe flow In fluid dynamics, the Poiseuille equation is a physical law that gives the pressure drop in a fluid flowing through a long cylindrical pipe. The assumptions of the equation are that the flow is laminar, viscous, and incompressible and the flow is through a constant circular cross-section that is substantially longer than its diameter. Many assumptions don’t really apply to the CV system, but the Poiseuille equation is a good approximation. Sutera, S. and Skalak, R. (1993). The history of Poiseuille's law. Ann. Rev. Fluid Mech . 25, 1-20.
Background image of page 6
Basic design of the circulatory system: pipe flow Laminar flow Turbulent flow Videos from YouTube
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Δ P = pressure difference r = vessel radius η = viscosity l = vessel length Flow (ml/min) Q = πΔ P r 4
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 35

Lecture 18.Circulation - LS2 Design of the circulatory...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online