You can define your own wind pressure profile (Wind Pressure vs Elevation) or wind speed (Wind Velocity vs Elevation) profile, or you can access wind load data from the following wind codes:
|
|
|
|
|
|
|
|
|
|
|
Generate Wind Loads
By defining a wind shape factor in the model input, CAESAR II allows you to define up to four wind vectors in the Static Analysis - Load Case Editor. Multiply the pipe exposed area by the equivalent wind pressure and the pipe shape factor.
CAESAR II includes insulation thickness in the cladding. You must also consider the angle to
the wind with your calculations.
Determine the Equivalent Wind Pressure
There are three ways to determine the equivalent wind pressure:
-
Selecting a regional wind specification (by building code)
-
Use the Wind Pressure vs Elevation user-defined method
-
Use the Wind Velocity vs Elevation user-defined method
Calculate the Total Wind Force on the Element
Calculate the total wind force on the element by using the following equation:
F = PeqSA
Where:
|
F = the total wind force on the element
|
|
|
Peq = the equivalent wind pressure (dynamic pressure) Calculate Peq for each end of the element and then take the average. The average applies uniformly over the whole length of the element. |
|
|
S = the pipe element wind shape factor |
|
|
A = the pipe element exposed area as shown in the figure to the right. |
If you enter velocity versus elevation table data, then the program converts the velocity to a dynamic pressure using the following equation:
P = 1/2 rV2
Where V is the wind velocity and r is the air density.
Enter the Wind Shape Factor on the piping input. For cylindrical elements, a value between 0.5 and 0.7 is used. A value of 0.65 is typical. The wind shape factor as entered is distributive. This means that the shape factor entered in piping input is carried forward and applies for all following elements until zeroed or changed.
There is no need to enter the same shape factor on each piping input segment. Zero
or disable the wind shape factor if the piping system runs inside of a building or
similarly protective structure.
Enter wind load parameters on the tab Wind Loads Tab (Static Analysis - Load Case Editor Dialog Box) of the Static Analysis - Load Case Editor. You can enter up to four different wind loads per analysis. These typically might be setup to model wind loads in the +X, -X, +Z, and -Z directions.