Animals utilize flow for mass transport in the body, and for locomotion in water or through the air. In this paper, flow for oxygen transport is mainly discussed. Principally, the oxygen transport is divided into two parts: one is in a region from the atmosphere to the respiratory organ, and the other is from the respiratory organ to the tissue. The former is termed respiration system and the latter is circulation system. Circulation system, which usually consists of a heart and vessels, is required in any animals greater than 3 mm. Mostly in invertebrates, the blood is pumped out from the peristaltic heart, and flows freely between organs (open circulation system). A vertebrate heart is a chamber pump, and distribution of the blood is regulated to each organ in closed circulation system. Respiratory pigment is common in most animals which saves cost for the oxygen supply and the volume of circulating blood, though blood viscosity increases. Respiratory organs are categorized into three groups: gills, lungs and tracheae. The gill, which is an evaginated organ, is familiar among aquatic animals but not among territorial ones because it requires large surface and thin wall resulting poor rigidity in air. However, the gill has higher efficiency than a lung in general due to the counter current flow. For air breathing animals, a lung which reduces water loss during respiration is necessary especially in dry circumstances. Compact avian lungs work together with the thin-walled air sacs which make unidirectional ventilation flow through the lung. In human lungs, ventilation flow through the bronchus augments gas transport with steady streaming and Taylor dispersion. An insect respires with forced-ventilation or auto-ventilation: abdominal/thoracic pumping or muscle pumping, through the tracheal network, and both ventilation methods sustain aerobic metabolism during flight.

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Mechanical properties of blood vessel walls are characterized by the terms like large deformation, strong nonlinearity, viscoelasticity, incompressibility, and anisotropy. The methods to study the mechanical properties of a material with such complicated characteristics is described first along with its structure. An example of stress/strain analysis of blood vessel wall considering residual stress/strain is introduced. Then, effects of smooth muscle contraction and relaxation on the mechanical properties of blood vessel wall are reviewed briefly with the methods to determine the smooth muscle contractility. Finally, a novel biomechanical role of vascular smooth muscle contraction and relaxation, i.e., control of intramural strain distribution, is proposed.

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Blood flow rate in microvessels whose diameter is less than 100μm is an important factor in determining mass transport of oxygen, nutrients etc. as well as in determining production of biologically active substances such as nitric oxide. Several flow measuring techniques used for experimental microciculatory studies are reviewed. A dual-slit photometric method is a most widespread technique and has moderate temporal and spatial resolutions but it lacks a spatial resolution in the line-of-sight direction. A dual-window method using conventional video signals has a merit of simultaneous velocity measurements in multiple microvessels but its temporal resolution is inadequately low. A laser-Doppler method has sufficiently high temporal resolution to analyze pulsatile flow in small animals and fits for surface microcirculation of solid organs as well as transparent tissues. Image processing method of optical flow and a high-frequency pulsed-wave Doppler ultrasound method are promising in the near future.

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This paper gives a brief survey from routine clinical methods to recent trend in the blood flow measurements. Dilution techniques, time-of-flight methods, electro-magnetic flowmeters, ultrasonic doppler methods, hot-film velocimeters, fiber-optic laser doppler velocimeters and whole-body methods are taken up, and their principles of measurements and their characteristics are explained.

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In the companion Part 1 paper, the jet breakup model incorporated into the VESUVIUS code was described. Herein, initial verification of the VESUVIUS jet breakup modeling by comparison of calculation results against the PREMIX PM10 and FARO L-14 experimental data is discussed. Predictions of the main experimental parameters, which include steam outlet flow rate and “interaction region” development for the PREMIX test and test vessel pressure and level swell for the FARO test, are shown to be in good agreement with the test data. In addition, the change with time of the jet axial profile and two-dimensional spacial distributions of the jet and coolant, which are not available as experimental data, are discussed in an attempt to further clarify molten jet behavior.

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Experimental and image processing techniques on visualization of multiphase flow by neutron radiography were presented. Priciples of the application of neutron radiography tomultiphase flow studies were discribed. Some examples of the applications were presented.

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