Bentley Hevacomp V8i – Tutorial Building and Analyzing a Small Office Building In this tutorial, you will use the data tools in Hevacomp V8i to design and build an energy model. In addition, you will use the load calculation tool in Hevacomp to run a peak load calculation on your building. Finally, you will use the simulation tools in Hevacomp to run analysis on your building.
Bentley Hevacomp V8i Workshop Tutorial Mechanical Designer and Simulation Bentley Hevacomp Mechanical Designer – Part 1 Data Input 1. Launch Bentley Hevacomp a. Launch Bentley Hevacomp V8i from your desktop shortcut.
b. Accept the default user by selecting OK. 2. Load Design Database/Create New Project a. Click on Design database to launch Hevacomp V8i Mechanical Designer b. To create a new project select Hevacomp Projects as the active folder in the left hand window. Click on the New Folder icon in the right hand window.
c. Enter Workshop Project for Path name and Pick Open. This will launch Design Database. d. Launch Windows Explorer. Browse to c:\Hevacomp Projects\Workshop Project. Right mouse click in this location to create a new folder. Name the new folder CADFiles. Copy the dxf files that were supplied with this workshop to this newly created folder.
3. Locating your Building a. Click on Building data to locate your building.
b. Select the Use world map globe to select a location from the weather map.
c. Use the zoom tools to zoom into the N.E. U.S. Zoom in to double‐click and select the West Chester 1W PA (w‐s). Make sure that your selection is listed under Selected location and pick the green check.
d. West Chester 1W PA (w‐s) should now be your selected location. e. Make sure your Building type is set to office. f. Click the green check to accept. 4. Viewing and Modifying Weather Data a. Click on Weather data to view the weather data for West Chester 1W PA (w‐s).
b. Browse the tabs at the top of this window to view/modify weather data for the selected location. c. Click on the New simulation days tab in this window. When changing weather locations it is necessary to add the energy year for the new location. d. The Add new energy year window should list the West Chester 1W PA (w‐s) location and the weather source. Click on the Add new energy year button next to this window to add the new location to be used for annual simulations. This window can also be used to add new summer and winter design days for simulation as needed.
e. Click on the green check to exit the Weather data dialog.
5. Viewing, Modifying and Adding Opaque Assemblies a. Click on Fabric data.
Hevacomp comes with a pre‐defined list of opaque surface assemblies. You can use this dialog to view and modify the existing assemblies using the editing functions provided. In this exercise we will create a new wall type to use on our project. b. Follow the steps listed below to create a new wall assembly: i. Click the Add wall button.
ii. Click on Add layer. Select 14. Plaster in the left window and 36. ASHRAE – Gyp. Board in the right window of the Add layer… dialog. Enter .5 for Thickness of layer and pick Ok.
You will notice that the wall is built from the inside to the outside. iii. Click on Add layer. Select 10. Insulation in the left window and 53. ASHRAE – Batt insulation in the right window of the Add layer…dialog. Enter 3.5 for Thickness of layer and pick Ok.
iv. Using the same method mentioned above add the following three layers to finish the new wall: 1. 15. Sheeting, 39. ASHRAE – Fiberboard Sheathing and .5 In. thickness. 2. 1. Air gap, Unventilated, 1.5 In. thickness 3. 6. Brick, 52. ASHRAE – Brick, 4 In. thickness v. Enter Workshop Wall for Wall description and set Wall type to Mass. vi. Click on the Update wall button to save your new wall assembly. vii. Click on the green check to exit the Fabric data dialog. 6. Viewing, Modifying and Adding Glazing Types a. Click on Glazing data.
Hevacomp comes with a pre‐defined list of glazing surface assemblies. You can use this dialog to view and modify the existing assemblies using the editing functions provided. The same basic principals are followed to create a new glazing type used to create a new wall assembly. We will use existing glazing types for our project.
b. After getting familiar with the existing glazing data dialog click on the green check to exit. 7. Viewing, Modifying and Adding Fin (External Shading Devices) Types a. Click on Fin data.
Hevacomp comes with a pre‐defined list of Fins (external shading devices). You can use this dialog to view and modify the existing assemblies using the editing functions provided. The same basic principals are followed to create new fin types used to create a new wall assembly. We will use existing fin types for our project.
b. After getting familiar with the existing fin data dialog click on the green check to exit. 8. Setting Standards for your Building This section focuses on setting up standard data for your room types to be used as a template or default information when you apply a specific room type to your energy model. a. Click on Standard.
In the Jet DDB Standard dialog there is the ability to change the Master database (changes will affect this project and all future projects) or the Project database (changes will only affect the current project). The left window contains a list of pre‐defined Building types that come with Hevacomp. Once a Building type is selected in the left window, a standard list of Room types for that Building type is displayed. b. Make sure Project database is selected. c. Select Office as the Building type in the left window. d. Select Open plan office in the right window. e. Click on Change database.
View the standard information for this room type in all of the available tabs. We will not be changing any of the default information for this room. g. After viewing all of the tab information, click on the red X in the upper right corner and pick No when it prompts you to accept the data changes. f.
9. Setting up Profiles a. Click on Profiles.
b. Click on the tabs for Temp., Plant, Gain, and Occupancy to view the pre‐defined lists of profiles for each category. All profiles are editable and you have the option of creating your own profile for a particular category. c. Click on the Annual schedules tab. This tab allows you to create holidays, change plant schedules and room schedules.
We will not be using profiles for this workshop. However, profiles can be applied throughout your project to specific categories which will have a direct impact on your simulation results. d. Since we did not make any changes to the profiles, click on the red X at the lower right to exit the dialog.
Once you have defined your location, weather data and standards, you are well prepared to start building your energy model. Make sure that before you proceed you have copied the dxf files supplied for this workshop to the CADFiles folder you created in step 2.
10. Building your Energy Model a. Click on CAD input.
b. You will be asked to import a dxf file for your first floor. Click on the green check and browse to c:\Hevacomp Projects\Workshop Project\CADFiles\ and select the file named Level 1.dxf.
c. In the new floor dialog box enter the following information: i. Floor: 1 ii. Floor description: First Floor iii. Angle for South: 0 The angle for south is determined by calculating the clockwise angle off of a vertical line through the orthogonal floor plan to true south. See diagram on page 34. iv. Finished floor level: 0 The finished floor level for the lowest floor is always 0. The additional floors/roofs are added on at the appropriate level above 0. So if the second floor is 14’‐0” above Level 1 and the Roof level is 28’‐0” above level 1 then 14 and 28 would be entered for their floor level respectively. The actual elevation is handled by the weather file. v. DXF units: inches vi. Click on the green check to accept the input.
Your DXF file will now be visible as a reference in the CAD input window.
Next, you will set up your CAD input defaults for your energy model. These defaults will be used to generate your 3D energy model. d. From the CAD Input main menu select Defaults, Default data. In the CAD input defaults window enter the following: i. Room Height: 14 ii. Wall Height: 14 iii. Partition Height: 14 iv. Door Height: 7 v. Window height: 7 vi. Sill height: 1
All other defaults in this window are ok. Click on the green check to accept your changes. Next we will begin to trace out our spaces, using the defaults, to create our 3D energy model. Under Defaults on the CAD input main menu, make sure that Ortho On and Snap On are selected. e. From the CAD input icons select the Pencil (Trace room) tool. Beginning in the upper left space you will use this tool to trace out the inside corners of the space. You will notice that the lines will snap to the corner of the spaces and will automatically make the lines straight due to the Ortho and snap settings. Prior to placing your last trace line in the space, you can right mouse click and pick Close room outline to complete your room. (You can use the Zoom (magnifying glass) tool to zoom into a specific space).
f.
Once you close your room, a New CAD room dialog box will appear along with a 3D graphic of
the room. These windows reflect the completed room based on the default entries from step d. above. Click on the green check to accept the default settings.
g. In the JetDDB Cad room creation dialog enter the following: i. Room reference: 1‐101 ii. Room description: Open Office iii. Zone No.: 1 iv. Standard building: Office v. room: Open plan office vi. Space type: Conditioned – non‐residential vii. Click the Set to Standard room button viii. Number of occupants: Next highest round number ix. Click the green check to accept your entries
Next, trace out the remaining rooms using steps e, f and g above. Create the rooms in the following order setting their Room reference as listed below. Finally use the information below to enter the remaining information about each space: Upper right – 1‐102 Middle – 1‐103 Lower left – 1‐104 Lower right – 1‐105 Reference Description Zone Bldg. Type Room Space Type 1‐102 Open Office 1 Office Open plan office Conditioned ‐ NR 1‐103 Entry/Lobby 2 Office Reception Conditioned ‐ NR 1‐104 Open Office 3 Office Open plan office Conditioned ‐ NR 1‐105 Open Office 3 Office Open plan office Conditioned ‐ NR Make sure you click on the Set to Standard room button and round off the Number of occupants to
the next highest round number. h. Once you have completed the creation of your first level spaces, click on the 3D view icon from the CAD input main window to view your completed first level in 3D.
11. Creating a New Floor from an Existing Floor You can create the next floor following the steps in Section 10. We are going to use the copy floor command by copying the first floor to create the second floor. a. In the JetDDB – CAD input for floor 1 window, select Floors, Copy floor from the main menu.
b. In the Copy floor dialog, fill in the following information in the New floor data section: i. Floor number: 2 ii. Floor description: Second Floor iii. Finished floor level: 14 c. In the New room reference area of the same window, change all of the prefix numbers from 1 to 2, and remove the (2) at the end.
d. Click on the green check to accept your settings for the new floor.
e. In the JetDDB – CAD input for floor 1 window, select Floors, Change floors. f. In the JetDDB CAD floors dialog, pick Floor 2 – Second floor and click the green check to switch to the second floor. (Notice the changes to the room reference numbers).
g. To change the referenced background, select Defaults, Default data from the main menu of this window. Under Floor data for the DXF file name click on the three dots to browse out to c:\Hevacomp Projects\Workshop Project\CADFiles\ and select Level 2.dxf and pick Open. Pick on the green check in the CAD input defaults window to accept the change.
h. Select Rooms, Delete CAD rooms. Pick the center of Room 2‐103. Select Yes to delete CAD Room 2‐103.
i.
Use steps e, f and g from step 10 above to trace out the two new spaces on level 2. Make the left (smaller) room reference 2‐103 and the right (larger) room reference 2‐103A with the following settings:
Reference Description 2‐103 Conference 2‐103A Open Area
Zone 5 5
Bldg. Type Office Office
Room Meeting room Open plan office
Space Type Conditioned ‐ NR Conditioned ‐ NR
As demonstrated, the copy floor command is the tool to use for similar levels in a building. Select the 3D view icon from the main menu to view your model. You will now see the second floor added.
12. Adding a Roof to your Building a. From the CAD input window (it doesn’t matter which floor is active) select Roof/floors from the main menu. b. Since we do not have a roof the software will prompt you to select a DXF file. In the Roof drawings dialog box, click on the green check. c. Browse out to c:\Hevacomp Projects\Workshop Project\CADFiles\ and select Roof.dxf and pick open.
d. In the New roof level drawing dialog, enter the following: i. Roof description: Main Roof ii. Level at base of roof: 28
iii. Click on the green check to accept your entries.
The dxf file for the roof will now be visible in a CAD input window similar to level 1 and 2. It is important to add your roof in sections so that you may be able to elevate certain points for a sloped roof. e. Select the Add roof section button.
Trace out the left section of the roof first using the same method as when you traced out a room space. g. Repeat the same process for the right section of roof. h. Select the Elevate edge button and click on the vertical line at the center of the roof. f.
i.
Enter 7 in the Junction height dialog box and pick the green check to accept.
j.
Select the Set up roofs tab in the Main Roof dialog window. Make sure that “Extend walls to
underside of roof and correct room volumes” is selected. k. Click on the Set up exposed roofs button. Click OK when prompted.
Using a similar method follow the steps below to set up ground and intermediate floors. l. Select the Set up ground floor tab in the Main Roof dialog window. Click on the Set up ground floors button. m. Select the Set up intermediate floors/ceilings tab in the Main Roof dialog window. Click on Set up intermediate floors button. n. Click on the green check to accept your entries. Select the 3D view icon from the main menu to view your model. You will now see your roof added to your building.
13. Adding Windows and Doors a. From the CAD input widow, select Floors, Change floors from the main menu. b. Select Floor 1 – First Floor from the JetDDB CAD floors dialog box and click on the green check to accept. c. To place a window, you will use the DXF background as a guide and your defaults that you set earlier. Zoom into your first space. Pick Rooms, Add a window from the main menu.
d. Hover of one edge of a window until you see the red X and pick that point as your first window point. Move to the end of a window (or edge of the room, windows will not place between walls) and select your second point to complete your window.
Select the 3D view icon from the main menu to view your model. Rotate your 3D view and you will now see your window added to your building using the defaults set up in Section 10 above.
e. Repeat the process above to add all of your windows to level 1 in the building. f. Use the same basic procedure to add the one external door on Level 1. Instead of picking Add a window under Rooms on the main menu, you will select Add a door. g. Repeat the Add a window process for all windows on level 2. Ignore the dxf graphics in room 2‐103A, draw the window from one edge of the room to the other.
14. Modifications to Existing Energy Model
a. Use the Floors, Change floors command from the CAD Input main menu to make your first floor active. The following exercise should only be done for singular modifications to your energy model. This is not the procedure that you should use to make global changes to your energy model. See Section 15 for global changes. There are two basic modifications that you can use in the CAD input module. You have the ability to change the structural make up of a space by hovering over a wall and double‐clicking, or you have the ability to change information about a space by double‐clicking on the center of the space. b. To edit the structure of Room 1‐101, hover over any exterior wall and double click to bring up the Change room dialog box. (This is the same dialog box that appears when you first create a room). All surface information about the room is available in this dialog box. You can first select a surface in the left hand window and make modifications to that surface in the right hand window. c. Select the first Exposed wall in the left window. Double click on the 1 next to Wall type in the right‐hand window and select (double click) wall type 12 from the wall type dialog.
d. e. f. g. h.
Click on the green check to accept your change. Double click on the center of Room 1‐101. In the Room: 1‐101 dialog, change the room to a Meeting room and click on Set to Std. room. Change the description to Conference. Change the Number of occupants to 13.
i. j.
Use the same step listed in b. above to select the lower wall of Room 1‐104. Click on the Use fins selection. Change the Fin type to 12.
k. Repeat this process for room 1‐105. l. Use the Change floors command to change the active floor to level 2. m. Using the same process described above, double click on the center of rooms 2‐101 and 2‐102 and change the zone number to 4. n. Change the zone number of rooms 2‐104 and 2‐105 to 6. o. In all cases above, you will click on the green check to accept your changes. 15. Making Global Changes to your Energy Model a. Back on the Design Database main screen, Pick the Global command.
The global command allows you to select a single room, multiple rooms or all rooms and make global changes to any of the following categories: Room Data
Occupancy Thermal Design Gains Lighting design Roof Floors Walls Windows Doors The command works the same for each category. First you select a room or group of rooms and select which category you wish to globally change. You will then select the new data for that category and globally change the information in all selected rooms. You also have the ability to restrict your global changes to a certain existing condition. The following exercise will use global command to change all wall types in all spaces to wall type 36 (This is the wall type we created in step 5 above). b. Select the Select rooms tab from the JetDDB global changes dialog box. c. On the right hand side of window click on the All rooms button.
d. e. f. g.
Select the Walls tab from the JetDDB global changes dialog box. Click on the box next to Wall type. Select Wall type 36 from the drop down list next to New data. Click on the globe to apply the global changes. (You must click on the globe to apply changes before clicking on the green check to exit this dialog.
Bentley Hevacomp Mechanical Designer – Part 2 Load Calculations 1. Determining Peak Month/Day a. Click on Maxi gain.
b. On the right hand window on the Select rooms tab, click the All rooms button and the Summary selection.
c. Click on the Design data tab. Make sure that the first month is January, the last month is December and the day of month is set to 15. Also, make sure that the Room design temperatures are set to Resultant and Include window fins are turned off.
d. Click on the Results tab to view the summary results. The summary results show that
the peak month/day is July 15th. This day will be used as the peak day for the ASHRAE RTS Load Calculation. e. Click on the Full button at the lower left to view the Full results of all selected rooms.
f.
Click on the red X to exit.
2. Using Peak Day/Month for Load Calculation (ASHRAE RTS) a. Click on ASHRAE RTS.
b. On the right hand window on the Select rooms tab, click the All rooms button and the Summary selection.
c. Click on the Design data tab. Under Outside conditions set your Design day to July 15 and click on the Recalculate button.
d. Click on the Results tab to view the summary of the peak load calculations for each room.
e. Click on the Full button on the lower left of this window to switch to full detailed results for each hour of the day for each room. f. Both the Summary page and Full result pages can be exported to Excel for further detailed calculations.
Bentley Hevacomp Simulator – Part 3 Simulations Launch the simulator by clicking on the Simulator icon from the Design Database.
1. External Shadow Simulation a. Click on the External shadows icon from the main Simulator window.
b. Set your desired design day and grading. Click on the play button to view the shadow simulation throughout the selected day. Use your mouse (left button) to spin the model during the simulation.
2. Summer Simulation A summer simulation can be used to simulate air temperatures in a room or rooms without mechanical cooling. You can then further use this simulation to determine what affect, if any, the addition of natural ventilation has on room temperatures, therefore reducing the need for mechanical cooling. a. Click on Design data from the main Simulator window.
b. Click on the Models tab and make sure that Multi‐zone air flow model is selected. This will ensure that the airflow animation will be available in the simulation results.
c. Click on the green check to accept your changes. d. Click on Summer simulation from the main Simulator window.
e. Click on the Select All icon to select all rooms. Set July 4th as your selected design day. Enter Summer Simulation under Description of simulation. Select Continue and Continue again on the next screen to run the simulation.
f.
Select Summer simulation from the Select Simulator results window. Click on the Graph tab to view the results in graph format.
g. You may view different rooms by changing the selection next to Select room at the bottom of the graph. Click on the animation symbol at the bottom of the graph to view the daily temperature animation.
h. You can change the hour of the day to view different room conditions throughout the day. Click on the green check when done. i. Back on the Simulation results screen, you may also choose to view the results in display (tabular) mode. 3. Maxi‐Gain Simulation A Maxi‐Gain simulation can be used to simulate different design scenarios in a building on an annual basis. These results can then be compared to other design scenarios to determine the better overall option for the project. a. Click on Maxi gain simulation from the main Simulator window.
b. Click on the Select all icon to select all rooms. Make sure that your Start month is January and your Finish month is December. Enter Workshop under Description of simulation. Click on Continue and Continue on the next window to run the simulation.
c. On the Simulator results viewer under Select Simulator results select Workshop and click on the Print numeric results tab to view the simulation results.
d. View your gain results. You may use these results to compare with other existing results to compare design scenarios.
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