3D Simple exercise
Exercise: Get started with the 3D view in IDA Tunnel
Purpose
Learn how to create a simple tunnel system in the 3D view of IDA Tunnel, map sections and routes to the 3D tunnel system, add fans and a fire and animate results.
Background
The 3D view of IDA Tunnel is used to translate the 1D simulation model of the schematic view to a 3D model of the actual tunnel system geometry. The advantages of using the 3D view are to get an easy way of error checking input data, such as section lengths, height coordinates, and cross section areas, the placement of fans, sensors, and fire etc. The 3D view also makes it easier to understand simulation results by animating the result variables as colors on the tunnel tubes and traffic movements as animated 3D trains.
In a real project the 3D model is generally modeled to represent the real geometry of the tunnel system as close as possible. To accomplish that it is beneficial to use drawings and 3D models of the tunnel system and stations as a background when creating the tunnel tubes. In “IDA Tunnel Application, 3D Tutorial” this is gone through in detail. In this exercise we will concentrate on creating a rough 3D model for error checking and results visualization.
Instruction
- Open an empty system in IDA Tunnel.
Drag in two entries/exits, two tunnel sections and a platform to the schematic view.
Connect these.
- Open the left section, edit the segments and change the left height coordinate to 30 m. Change the right length coordinate to 700 m and the right height coordinate to 15 m. Change dxMax on the section form to 200 m.
- Make the same settings on the right section, except that the left height coordinate is set to 15 m and the right height coordinate is left at 0 m. Set the platform width to 15 m, height to 5.5 m and hFloor to 15 m.
- Go to the 3D view. Choose Add… > New tube. Select RAIL-TUNNEL-PROFILE in the Defaults for new tubes dialog. Click the ‘>’ button and choose New resource. Give the new resource the name platform profile. Open the profile, select the perimeter and drag its handles so that its width extends from -4 m to 10 m and its height is 6.5 m. Click Ok. Click Ok on the Defaults for new tubes dialog. Right click in the 3D view and choose Done.
- Place the mouse pointer at the left of the tunnel tube. Right-click and choose New tube while holding down the shift-key. Create a new cross section profile resource called tunnel profile with a width from -4 m to 4 m and a height of 5.6 m. Click Ok. Click Ok on the Defaults for new tubes dialog.
Zoom out the 3D view (hold down right mouse button and move the mouse downwards). Select the left handle and drag it to the left. Hold down the ctrl-key and click to the left of the tunnel tube to add a third handle. Move the handles so that a smooth tunnel tube is created. Right click in the 3D view and choose Done.
Add another tunnel tube on the right in the same way.
The ends of tunnel tubes should be placed at a certain distance to be able to create a smooth transition between them.
- Select both the left and middle tunnel tubes holding down the shift-key. Choose Tube connection from the right mouse button menu. The tubes are connected with a smooth transition.
Do the same thing on the right side.
- Select the 3D plan tab and drag it away from the other tabs. Place the windows so that you can see both the 3D view and the schematic view. You can use Window > Tile Horizontal.
Select the platform in the schematic view and drag it to the platform tunnel tube in the 3D view. Release it somewhere in the middle of the platform tunnel tube
- Drag the left tunnel section to the 3D view. Make sure that the red arrow in the schema and the green arrow in the 3D view point in the same direction. Otherwise one of them should be flipped. To flip the 3D arrow click the right mouse button while dragging over the tunnel tube. To flip the schema arrow click the right mouse button while dragging outside of any tunnel tube.
If the arrow in the 3D view is read the section does not fit. In that case edit the tunnel tube and make it longer.
Map the sections without any distance between them.
- Map the right section in the same way.
The tunnel tubes and tunnel tube connections of the 3D model serve as placeholders for the sections and platforms of the schematic view. There is generally not a one-to-one mapping between the sections and platforms and the tunnel tubes of the 3D view. The tunnel tubes in the 3D view should ideally extend up until the point where the cross section of the tunnel changes or where the tunnel is branched.
- We will adjust the lengths of the tunnel tubes to the mapped sections. Right-click on the platform tunnel tube and choose Edit. Move the two handles so that they are slightly inside the purple platform on both sides. Choose Done from the right-mouse button menu.
Edit the left and right tunnel tubes in the same way making them slightly longer than the sections.
Remap all the sections by first right-clicking on a section or platform in the schematic view and choosing Remove from 3D view. Then map the platform and sections by dragging them from the schematic view again. Remapping should always be done after editing a tunnel tube.
- Rotate your view so that you see the tunnel tubes from the side (hold down left mouse button and move the mouse upwards). The purple representation of the platform in the 3D view is placed above the tunnel tube since the platform has hFloor 15 m. Right-click on the platform tunnel tube and choose Edit.
Hold down the shift-key, click somewhere in the middle of the tunnel tube and drag it upwards. Stop when the coordinates in the lower right corner shows 15 for the z-coordinate. Choose Done from the right-mouse button menu.
Edit the other two tunnel tubes and drag the handles upwards while holding down the shift-key. Use the purple sections as a guide. Remap the sections.
- On the schematic tab select the ‘…’ button next to the Ambient button and choose Measured weather. Choose the weather data ‘Stockholm, Bromma-1977’ from the database.
- On the Global tab change tauWall to 4000 h.
- On the Schematic tab, select first the left entry/exit and then the right entry/exit and choose Add path report. Select path reports for air temp, wall temp, relative humidity, air speed, extinction coefficient, and mold growth. Click Create.
- On the Schematic tab, choose Select output and select the following under Animation: traffic, air temp, wall temp, relative humidity, air speed, extinction coefficient, and mold growth.
- On the Schematic tab, select Simulation data and change Maximal timestep to 99 h on the advanced tab. Change To to May 1st. Click Run on the schematic tab.
- Double click on Path report on the Schematic tab. Double click on Air speed and Air temperature in the Path report form.
The changes in air speed and temperature are totally driven by the climate.
The same results can be animated with colors on the tunnel tubes in the 3D view. Go to the 3D view. Choose Results, select result to animate and click Show.
- Let us add some traffic to the system. On the Schematic tab, select first the left entry/exit and then the right entry/exit and choose Add route.
On the 3D view, turn off the visibility of sections by choosing Show > Visual filter and unselect Section, platform, plenum models. Select a rail track in each tunnel tube. Use the shift-key for multi-select. Right-click and choose New route.
Drag the Route in the Routes list on the schematic view to the route in the 3D view. When the route is released its direction is seen both on the schematic view and on the 3D view. If the direction is wrong in the 3D view it can be flipped by right-clicking on the route in the 3D view and selecting Flip route.
On the Schematic tab, select Simulation data and change To to 01:00:00 January 1st. Click Run on the schematic tab.
- Look at the path report for air temperature. The periodic train-driven variations can be clearly seen.
- Go to the 3D view. Choose Results, select air temperature and traffic and click Show. The train movements are shown with animated trains and the air temperature is shown with colors on the tunnel tubes. The trains are stopping at the platform for a while before they continue.
- Let us add a fire. Place the mouse pointer on the left tunnel tube, about 200 m from the platform. Choose Fire from the right mouse button menu. Give it a length of 10 m and a heat from fire of 10 MW. A fire icon is show in the 3D view.
- Open the route on the schematic view and set nextDep to 5000 s so that no trains are run during the simulation. Run a simulation.
- Animate the extinction coefficient. The smoke from the fire can be seen propagating up the tunnel tube driven by the stack effect.
- Place the mouse pointer on the left tunnel tube, about 100 m from the entry. Right-click and choose New section feature > Jet fan(s). A fan icon is shown in the 3D view.
Rerun the simulation.
- Animate the extinction coefficient. The smoke is initially propagating up the tunnel tube driven by the stack effect. After a while the air flow from the fan is able to change the direction of the smoke propagation and it propagates down the tunnel instead.
