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Momentum Thickness Formula:
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Momentum thickness is a measure used in fluid dynamics to quantify the momentum deficit in a boundary layer due to viscous effects. It represents the distance by which the boundary would have to be displaced to compensate for the reduction in momentum flux caused by the boundary layer.
The calculator uses the momentum thickness formula:
Where:
Explanation: This formula provides a simplified relationship where the momentum thickness is approximately one-seventh of the hydrodynamic boundary layer thickness.
Details: Momentum thickness is crucial in boundary layer analysis as it helps determine the drag force on surfaces, predict flow separation, and analyze the momentum loss in fluid flow due to viscous effects.
Tips: Enter the hydrodynamic boundary layer thickness in meters. The value must be positive and greater than zero.
Q1: What is the difference between displacement thickness and momentum thickness?
A: Displacement thickness represents mass deficit, while momentum thickness represents momentum deficit in the boundary layer.
Q2: When is this simplified formula applicable?
A: This 1/7th power law approximation is typically used for turbulent boundary layers with zero pressure gradient.
Q3: How does momentum thickness relate to drag coefficient?
A: The momentum thickness is directly related to the skin friction coefficient and can be used to calculate drag on surfaces.
Q4: What are typical values of momentum thickness?
A: Momentum thickness values depend on flow conditions but are typically much smaller than the boundary layer thickness itself.
Q5: Can this formula be used for laminar flows?
A: No, this specific 1/7th relationship is derived for turbulent boundary layers. Laminar flows have different relationships between momentum thickness and boundary layer thickness.