Tuning the model

To tune the model you need to set values for each of the vessels. (I would be pleased to hear any suggestions for these values.)

With the heart stopped all pressures should equalise to the "Circulatory filling pressure". ( 7 mm Hg.)  Guyton

The settings for resistances have no effect on the final balance, they alter the time taken to arrive at this balance.

Resistance

Resistance equals Pressure difference divided by Flow . Its is measured in Peripheral Resistance Units.  These are the units that result when pressure is measured in millimetres of mercury and flow is measured in millilitres per second . (PRU=mmHg*sec/ml)

Total systemic resistance is about 1 PRU because blood flow is about 100 ml per second and the pressure gradient down the systemic vascular tree is about 100 mmHg.

The pulmonary vascular resistance is about 0.1 PRU's

Compliance

Working on a Systemic pressure of 120/80 for a stroke volume of 70 ml produces a compliance for the Systemic artery of 70 ml per 40 mmHg roughly 2.

Guyton suggests the volume of the major arteries is 750 ml at 100 mmHg and 500 ml at 0 mmHg.  Again a compliance of about 2.
He suggests venous volume of 3250 ml at 20 mmHg and 2600 ml at 0 mmHg giving a compliance of 30.  (15 times greater than the arterial side)

Pulmonary artery has a pressure of 22/8 with a stroke volume of 70 ml suggesting a compliance of 5 (70/14)

Volumes

I have derived the following volumes from various sources.  It would be nice to have a solid reference. (and values for children)

These are the values that the model should equilibrate to.