Principles of Fluid Properties Flashcards
In poisseuilles equation, what variables are proportional to flow rate and what variables are not proportional to flow rate?
Proportional = change in pressure and diameter
(P, d)
Not proportional = length and viscosity (L, n)
Equation of Bernoulli’s Effect
Change in pressure = 4(v)^2
To maintain flow continuity, flow speed must do what through a stenosis?
Increase
What happens to velocity of flow when the diameter of a vessel decreases?
Increases
What happens to the magnitude of pressure drop as flow speed increases?
Pressure drop at the point of a stenosis increases
What is rouleaux flow?
Stacking of RBC’s due to their size and discoid shape
What conditions cause rouleaux flow?
Infection
Muliple myeloma
Macroglobulinemia
Inflammation
Cancers
Diabetes mellitus
What is required for flow to occur?
Pressure difference
Volumetric Flow Rate equation
Pressure difference/ Flow resistance (poise)
Flow Resistance formula
L x poise (viscosity)/radius
What happens to flow resistance with increasing radius?
Decreases
What happens to flow resistance when length increases?
Resistance increases
What happens to flow resistance when viscosity decreases?
Flow resistance decreases
Where does plug flow occur?
Entrance of a vessel
Where is flow speed maximum in laminar flow?
Center of the tube
