Introduction to Long Wave Equations in Civil Engineering

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the purpose of determining the local combined surface and bottom stress coefficient 𝐾𝑠𝑏 𝜏𝑠 + 𝜏𝑏 = 𝐾𝑠𝑏 𝜌𝑊?

  • To calibrate wind/bottom stress setup calculations (correct)
  • To calculate wind speed at a specific site
  • To estimate the setup due to hydrostatic forces
  • To measure Coriolis forces in nearshore water segments

In which direction is the bottom stress typically drawn in relation to the surface wind stress in the setup calculations?

  • Same direction (correct)
  • Vertical direction
  • Perpendicular direction
  • Opposite direction

What does Δ𝑆𝑤 represent in the context of the setup calculations mentioned?

  • Wind speed near the shore
  • Depth of the water segment
  • Change in setup due to wind and bottom stresses (correct)
  • Distance between two hydrostatic forces

How is the component of wind velocity in the 𝑥 direction 𝑊𝑥 utilized when the wind is blowing at an angle 𝜃?

<p>To evaluate wind/bottom stress setup (D)</p> Signup and view all the answers

What does the setup coefficient 𝐾𝑠𝑏 𝜏𝑠 + 𝜏𝑏 = 𝐾𝑠𝑏 𝜌𝑊 act as according to the provided text?

<p>An 'all inclusive' calibration factor (B)</p> Signup and view all the answers

Why is it beneficial to have adequate wind, pressure, and setup data from a previous storm at a specific site?

<p>To calibrate subsequent wind/bottom stress setup calculations (B)</p> Signup and view all the answers

What is the primary purpose of the 𝑆𝑃𝐻 and 𝑃𝑀𝐻?

<p>To predict storm surges and wave patterns (B)</p> Signup and view all the answers

What is the range of the inflow angle typically observed in a hurricane?

<p>10 to 30 degrees (A)</p> Signup and view all the answers

What is required to convert the surface wind speed to a resulting surface stress for the equations of motion?

<p>A wind stress drag coefficient (C)</p> Signup and view all the answers

Who developed the commonly used relationship for wind stress drag coefficient?

<p>Van Dorn (B)</p> Signup and view all the answers

What is the formula for wind-induced shear stress on a surface?

<p>Drag coefficient times air density times wind speed squared (B)</p> Signup and view all the answers

At what elevation is the surface wind field plotted?

<p>10 m (A)</p> Signup and view all the answers

What type of waves are typically modeled using long wave equations?

<p>Shallow water waves (B)</p> Signup and view all the answers

What are the horizontal coordinates considered in the long wave equations?

<p>𝑥 and 𝑦 (C)</p> Signup and view all the answers

What is the effect of Coriolis acceleration on the long wave equations?

<p>It can be neglected in certain situations (D)</p> Signup and view all the answers

What is the significance of the volumetric flow rate per unit width of vertical section (𝑞𝑥 and 𝑞𝑦) in long wave equations?

<p>It is used to consider horizontal flows in terms of average velocity (D)</p> Signup and view all the answers

Which of the following is generally neglected in the long wave equations?

<p>Vertical flow velocities (B)</p> Signup and view all the answers

What assumption is made about the periods and 𝑑/𝐿 values of waves modeled by long wave equations?

<p>They have long periods and low 𝑑/𝐿 values (A)</p> Signup and view all the answers

What is the primary condition for determining the final surface profile and nodal line position?

<p>The setup and setdown water volumes are equal (C)</p> Signup and view all the answers

What is the unit of measurement for the static pressure setup calculated using Eqs.(4) and (8)?

<p>Meters (C)</p> Signup and view all the answers

What is the purpose of assuming a nodal line position in the setup calculations?

<p>To calculate the setup and setdown water volumes (B)</p> Signup and view all the answers

What is the relationship between the setup and setdown water volumes on the leeward and windward ends of the bay?

<p>The setup volume is equal to the setdown volume (C)</p> Signup and view all the answers

What is the unit of measurement for the pressure differential used in the calculation of static pressure setup?

<p>Inches of mercury (B)</p> Signup and view all the answers

What is the purpose of using Eqs.(4) and (8) in the calculation of static pressure setup?

<p>To calculate the static pressure setup (A)</p> Signup and view all the answers

What is the relationship between wind stress and bottom stress in the context of water surface slope calculation?

<p>Wind stress and bottom stress are directly proportional (A)</p> Signup and view all the answers

How can Eq.(7) be used to calculate setup for a shore normal profile on the open coast?

<p>By calculating setup for each segment and summing them (A)</p> Signup and view all the answers

What is the recommended value for 𝐾𝑠𝑏 when no better information is available?

<p>1.1𝐾𝑠 (C)</p> Signup and view all the answers

What is the significance of the water surface slope Δ𝑆𝑤 /Δ𝑥 in the static balance equation?

<p>It is the driving force for the balance (C)</p> Signup and view all the answers

How can Eq.(7) be applied to enclosed bays?

<p>It can be applied with caution (C)</p> Signup and view all the answers

What is the procedure for calculating setup for a shore normal profile on the open coast?

<p>Start from the offshore point and move towards the shore (A)</p> Signup and view all the answers

Flashcards are hidden until you start studying

Use Quizgecko on...
Browser
Browser