183_notes:drag

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183_notes:drag [2021/02/04 23:36] – [Fluid Resistance] stumptyl183_notes:drag [2021/02/04 23:39] (current) – [Models of fluid resistance] stumptyl
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 === Laminar drag === === Laminar drag ===
  
-For a situation where the Reynolds number is low (e.g., a small, slow-moving object in a viscous fluid), the fluid resistance is proportional to the velocity of the object:+For a situation where the __Reynolds number is low__ (e.g., a small, slow-moving object in a viscous fluid), the fluid resistance is proportional to the velocity of the object:
  
 →Fdrag=−b→v →Fdrag=−b→v
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 →Fdrag=−6πηr→v →Fdrag=−6πηr→v
  
-where η is the fluid viscosity.+where** η** is the **fluid viscosity**.
  
 +\\
  
 === Turbulent drag === === Turbulent drag ===
  
-For a situation where the Reynolds number is high (e.g., a large, fast-moving object in a less viscous fluid), the fluid resistance is proportional to the speed of the object squared:+For a situation where the __Reynolds number is high__ (e.g., a large, fast-moving object in a less viscous fluid), the fluid resistance is proportional to the speed of the object squared:
  
 →Fdrag=−cv2ˆv →Fdrag=−cv2ˆv
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 →Fdrag=−12ρCdAv2ˆv →Fdrag=−12ρCdAv2ˆv
  
-where ρ is the density of the fluid, A is the cross-sectional area of the object in the fluid, and Cd is the drag coefficient of the object, which is often measured experimentally.+where ρ is the// density of the fluid//, A //is the cross-sectional area of the object in the fluid//, and Cd //is the drag coefficient of the object, which is often measured experimentally//.
  
 +\\
 === What about "medium" Reynolds numbers flows? === === What about "medium" Reynolds numbers flows? ===
  
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