[Example 4] Flow in a real river(single cross section)
Select Solver
In the [Select Solver] window, Figure 81 , select [Nays2d+] and click [OK].
Importing River Survey Data
In the window, Figure 82, select [Import], [Geographic Data], [Elevation(m)]
Chose [single.riv] in the window, Figure 83 and open. The cross sectional survey data “single.riv” can be downloaded from, https://i-ric.org/yasu/fw/rivfiles/single.riv
A message window may appear telling “Problems Fund i Data” as Figure 84 ,but just click [OK]
Select [Middle point of left and right bank] in the [River Survey Data Import Setting] window as Figure 85 , and click [OK]
Figure 86 riv file import complete.
Grid Generation Conditions
From the main menu, select [Grid] and [Select Algorithm to Create Grid] as, Figure 87
Select [Create grid from river survey data] from the window, Figure 88 , and click [OK].
As shown in Figure 89 , a channel with cross sections with both ends’ blue circles are displayed.
Grid Generation
Select any side of one of the cross section line, right click, and chose [Add Division Points].
Set [Division Number], set [4] in this example, and click [OK] (Figure 91 )
Select one of the opposite side of the cross sectional line we selected in Figure 90 , right click, and chose [Add Division Points] (Figure 92 )
Set [Division Number], set [4] as a same number we set in Figure 91 for the symmetry.
Along the channel direction, division points are set all at once. Select [Grid], [Add Division Points Regionally] from the menu bar. ( Figure 94 )
Chose [Specify target distance division points]. set distance [70] in this example, and click [OK].( Figure 95 )
When the setup for division points are completed, a plane map with yellow circle points appears as Figure 96
Select [Grid], [Grid Create] from the menu bar.( Figure 97 )
Confirm the grid generation range painted with blue, and click [OK].
Answer [Yes] when you asked [Do you want to map?] as Figure 99
Completed grid is shown as Figure 100
Bed configuration and channel shape can be confirmed by putting checking marks at, [Grid], [Node attributes] and [Elevation (m)]. ( Figure 101 )
Computational Condition
Select [Calculation Condition] and [Setting] from the min menu as Figure 102 .
Set [Time unit of discharge] as [Hour] and click [Edit], ( Figure 103 )
Set discharge hydrography as Figure 104, constant for 3 hours with 2,000 qms, and click [OK].
Set [Time and bed erosion condition] as Figure 105 .
Set “3D Velocity Profile” as shown in the figure Figure 106 , and click [Save and Close] to exit.
Launch Computation
From the menu bar, select [Simulation] and [Run].
Answer [Yes(Y)] when you asked [Save the project?] as Figure 108
Simulation starts. Figure 109
Click [OK] when the message [The solver finished calculation] as Figure 110
Display Computational Results
After the companion finished, form the main menu, by selecting [Calculation Results] and [Open new 2D Post-Processing Window], a new Window appears as Figure 111 .
Depth
n the object browser, put the check marks in “Scalar (node)” and “Depth[m]”, right-click and select “Properties”. The “Scalar Setting” window Figure 112 appears.
Set the values as shown in Figure 112, and click [OK], then Figure 113 appears.
Display Background Image
Select from the main menu, [File]->[Property] ( Figure 114 )
From the “Project Property” window, click [Edit] at [Coordinate System] .. _04_haikei_02:
Input “Japan” in the [Search] window, and chose the one with “XII” from the items with [EPSG:….] as Figure 116 . See more detail on coordinate system of Japan at http://www.gsi.go.jp/sokuchikijun/jpc.html
Click [Close] of [Project Property] window of Figure 117
Put a check mark in a box in front of [Background Images(Internet)] and one of the items listed below, e.g., [Google Map (Sattelite Image)] as Figure 118
Velocity Vectors and Streamlines
Since the operation method is the same as the previous section, it will be omitted.
Particle Animations
Put check mark at [Particles] and [Velocity] in the object browser, put time bar back to zero, and push black button, ( Figure 119 ). Particle following the depth averaged velocity starts as Figure 120 .
表面流速に乗ったパーティクルを赤色で表示する. 「パーティクル」「SurfaceVelocity」に☑を入れて,「パーティクル」を右クリックして 「プロパティ」を選択すると,「パーティクル設定画面」 Figure 121 が表示されるので,図のように設定して[OK]をクリックする. タイムバーをゼロに戻して,プレイボタンを押すと Figure 122 の 表面流によるパーティクルアニメーションが表示される.
同様な手続きで,「BottomVelocity」を選択すると,底面流によるパーティクルを表示出来る.