When measuring blood pressure in humans the focus is on systolic and diastolic, which is the maximum and minimum. Higher pressure should mean higher blood velocity if I think loud. I just want to now 1) if this is true, and 2) if so then would the velocity provide a good estimate of blood-pressure.
generally if you increase pressure, the kinetic energy will increase................ There is a relationship exists.
There is a relation between the velocity (profile) and the gradient of the pressure along the veins and arteries.
If we assume the veins or arteries as tubes (horizontal) and the flow of the blood as laminar, and if we do not consider the gravitational force, then
v(r) = (1/(4k)) (dp/dx)(R^2-r^2)
where k is the viscosity coefficient, (dp/dx) is the gradient of the pressure along the tube (vein or arteries) with length (dx), R is the vein radius and r is the distance from the center (axis) of the vein.
As you can see the velocity depends on the distance from the axis, it is maximum when r=0 and v=0 when r=R (which is also the boundary condition).
If we assume more complex conditions when the veins and arteries are not with constant radius and not horizontal, then the change of the pressure is due to gravitational field, viscosity, change of the velocity because of different radius in different parts, and the change on the pressure due to the acceleration of the fluid. In such general situation we obtain the so called generalized Bernoulli equation. Velocity will depends not just on the radius, but also on the distance.
As reference:
RK Hobbie, BJ Roth, Intermediate physics for medicine and biology, fourth edition.
And maybe any Fluid Dynamics book could be helpful.
I am neither good in maths nor statistics. But what i assume is that blood pressure increases with increased blood flow.
For example,
when blood decreases, one chemical is released which constrict the blood vessels (decrease diameter of blood vessel). We have studied in physics that decrease in diameter, increase the flow of liquid. So, in this perspective blood pressure increases with increase in blood flow.
and vice versa
I hope this answer will work for you
There is a relation given by Bernoulli equation. But in the simple case when motion
is horizonal and steady flow , increasing velocity will decrease pressure .
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