David Butts Gannett Fleming MP3724-L In the Building Information Modeling (BIM) world, there are still many users who have AutoCAD MEP but aren't ready to make the move to Autodesk Revit for a variety of reasons. This hands-on lab focuses on the HVAC side of AutoCAD MEP, and will include a review of new features for duct layout, sizing duct systems, creating quick parametric parts, and leveraging the spaces and zones for analytical models. This lab will help you get more out of your AutoCAD MEP model and take even more steps toward the BIM environment! Learning Objectives At the end of this class, you will be able to: Leverage spaces and zones for gbxml export, working with external applications such as Trane Trace Describe new layout features, such as reducing elbows and transitions Describe duct sizing methods, engineering units, and best practices Create content as parametric multi-view parts About the Speaker David is an energetic, highly motivated BIM specialist with Gannett Fleming, a large engineering and architectural firm based in Camp Hill, Pennsylvania. His Autodesk product expertise extends to Revit MEP, AutoCAD MEP, Revit Architecture, AutoCAD Architecture, Navisworks, Green Building Studio, Plant 3D and more. David's responsibilities include managing the implementation of BIM for the engineering aspects of the firm, providing training, customization, and programming for the Autodesk MEP product lines. He also works as BIM manager for several projects (including water and wastewater treatment, transit, and pharmaceutical), and has also worked as a project manager for Autodesk-related specialty projects. Prior to joining Gannett Fleming, David worked in the Autodesk reseller channel as a training manager and applications engineer for the Autodesk building design and construction product line. He is based in the firm's Raleigh, North Carolina office and has been speaking at AU for many years. Email: dabfvnc1@nc.rr.com
Introduction AutoCAD MEP is the long-running AutoCAD-based engineering design and drafting solution for mechanical, electrical and plumbing projects. Based on AutoCAD Architecture 2012, this object-oriented software can dramatically improve coordination while helping to improve the construction document process. In this lab, we re going to focus on the HVAC features. We ll cover some tools that have been in the program for a while and we ll also look at new and improved tools to help you create a more accurate model. So let s get started and get the most from your AutoCAD MEP! Leveraging Spaces and Zones When you re using AutoCAD MEP, It pays to define spaces and zones, These objects do more than just help place room name tags on the drawings. Spaces are analytical areas, storing information about the size, volume, space type, conditions and more. They can be defined by a polyline, or bound by walls. When AutoCAD Architecture objects for walls, doors and windows are used, the space automatically recognizes and links to these objects so if they are changed, added or removed, the space will track them. Spaces are attached to Zones, which track the total amount of area and volume of the group, and adds analytical data that can be used to determine the heating and cooling loads in the building. Zones can also be attached to other zones, and can be graphically represented on plans. Let s take a look at how we can add spaces to a model, associate them with a zone, and then edit their data. 1. In the class dataset folder, open the AU 2011 MEP Base.dwg file. 2. Start by adding spaces to the model from the Home tab, select the Space tool: 2
3. Check the properties palette make sure the Create Type option is set to generate. 4. Check additional settings for the space height, type, and more: 3
5. Read the command line use the General all option to automatically place spaces in all enclosed areas of the model: 6. Note spaces will not be created in enclosed areas if a space is already defined. Press Enter to complete the command. 7. Once the spaces are placed, select one of the spaces. Review the properties let s name this particular space Lobby: 4
8. Change to the Extended Data tab on the properties palette. Scroll down to the property sets area. Set the space type to Lobby, and the condition type to Heated and Cooled: 9. Go back to the Design tab select the Space Zone Manager: 10. Since the lobby was selected, it properties show up automatically in the dialog. The right panel shows general information, contents, calculation types and modifier styles: 5
HVAC in AutoCAD MEP: New and Improved 11. At the bottom of the dialog, check the boxes to show all zones and spaces, and to show space surfaces: 12. Expand the lobby. Scroll through and note all of the openings in the walls their properties are currently grayed out because the space is associative.. If the door, window or wall is changed, the space will be updated: 6
HVAC in AutoCAD MEP: New and Improved 13. Select OK to exit the space/zone manager. Use the view cube to change to a 3D point of view: 14. While the lobby is still selected, go back to the space zone manager. Note how it s highlighted in the drawing. 15. Select OK to exit the space zone manager. Use the view cube to return to the Top view. 16. From the Analyze tab, select the Zone tool: 7
17. Place a zone outside of the building as shown: 18. Pick the zone a plus sign grip will appear. Pick it, then pick the spaces as shown below: 19. Next, go to the properties dialog while the zone is still selected. Under Properties, name the zone 1 st North. 8
20. Review the dimensional properties of the zone: 21. You can also add and remove spaces as needed for the zone. The zone is a required object you can t perform an energy analysis without at least one zone in the model. 22. Take a few minutes, and edit the properties of the spaces. Set the space type offices around the perimeter (note you can select more than one space at a time, and edit the properties as needed). Save your model before you start the next section/ Once zones are defined, you export to a gbxml, which can be imported into analysis applications such as Trane Trace, IES Virtual Environment and Ecotect Analysis. If you ve gotten behind, open the AU 2011 MEP Base Export gbxml.dwg file to continue. 23. To export the space and zone data, go to the Analyze tab select the Export gbxml tool: 9
HVAC in AutoCAD MEP: New and Improved 24. This dialog lets you: Define where you want the exported gbxml file to be located; select Zones to export; Set the building type and zip code; Start and monitor the progress of the export; And show where errors may have occurred if an error occurs, a message will appear: The icons on the right side allow you to highlight the selected object, and fix the error, should one occur. 10
After the export is complete, you can now open the file with notepad, review the output, and import into your analysis application. By using spaces and zones, you save a tremendous amount of input time over traditional methods. Duct Layout New and Improved AutoCAD MEP 2012 includes lots of improvements to make duct layout easier and more fun. In this class, we re going to work on these tasks, since they re either a new tool or in a new location, to make it easier to: - Creating a vertical riser - Creating a sloped duct - Define Routing solutions - Add Offset Transitions We ll start with the drawing, AU 2011 MEP Base Duct Layout. 1. Zoom to the north side of the building: 2. Start by drawing a duct from the VAV pick it, and then use the grip to add the duct. Add the main as shown: 3. To connect the duct to the main, pick an air terminal use the plus sign grip to start the duct. On the properties palette, change the elevation to 11 6. Under the advanced section, check the branch fitting make sure it s set to use a Takeoff for the connection this is a new location for this feature: 11
4. Pick the main duct look for the duct connector snap, and make the connection to the main choose Accept when prompted. 5. Notice how the takeoff is added the fitting types are controlled by the duct routing preference. 12
HVAC in AutoCAD MEP: New and Improved Here s another point AutoCAD MEP added a vertical riser on its own, based on a Duct preference setting. To see how this works, go to the Manage tab, and pick the Duct preferences tool: Duct preferences include settings to make adding duct easier. The first one we re looking at is the elevation changes feature, which has been in the program for a while. By having this checked, you simply have to type in the new elevation, and the vertical riser is added. The second is a new feature, the Elbow layout options. You get two options here the first forces the duct routing preferences to use a reducing elbow first, if the size changes. The second adds a non-reducing elbow, and places a reducer directly on the fitting to make the size adjustment: 13
When creating a vertical riser, there are a couple of rules: There has to be enough elevation change for the fittings to fit, so consider using different elbow types, such as mitered instead of long radius; You have to have the automatic create riser turned ON under duct preferences. Let s look at how this works. 1. Start by picking the VAV box in the north corridor. Select the plus sign grip to start adding a duct: 2. Immediately go to properties check the duct preferences first under routing options: 14
3. Make sure the automatic riser option is checked. Select OK to close the dialog. 4. Draw a short section of duct based on the elevation of the VAV box, the duct should be at 12 3. From the properties dialog, set the elevation to 10 the vertical drop will appear once you press enter: 5. Go ahead and pick a second point this duct will be centered at 9-9, since that the amount of room that s available. Regardless of what elevation you picked it s got to have enough room to place the fittings, so it forces the lower elevation. 6. Next, go back to duct preferences and turn off the automatic riser. To add a sloped duct, start a new duct run with the plus sign grip from the last duct segment. 7. On the properties palette, change the elevation to 11. 8. Notice the riser doesn t appear, so pick a second point a sloped duct will be added up to this elevation, so give yourself a little room you may get a warning about custom layouts, so pick Yes to continue: 15
9. The next point you select will place a duct at 11, running flat so you can use this method to rout duct around other items, and avoid conflicts: 10. Here s a section view of the results you can see this by selecting the south face of the view cube: From this view, you can select grips on the low duct, and drag it up to a different elevation if needed. 11. Let s take a look at another way to add the sloped duct delete the sloped duct and fittings you just added, from the section view (select it, and press the Delete key): 16
12. Pick the low duct, and then pick the plus sign grip draw a duct to the end of the higher duct: 13. Use the duct end connector to snap to the end of the higher duct. 14. You ll get a number of routing solutions type in N and press enter to cycle through the options. When you get the 45 s, type in A for accept, and press enter: Again as long as you have room to make the fittings, it will create the run. Let s see how the elbow layout options work. 1. Change back to a plan view, and select the last duct segment pick the plus sign grip to start drawing another duct: 17
HVAC in AutoCAD MEP: New and Improved 2. On the properties palette, go to preferences make sure the layout option for using a reducing elbow is set: 3. Select OK to exit the preferences dialog. Stay on properties, and go change the diameter to 12 : 4. Pull your mouse straight down to place the elbow you ll get the Choose a Part dialog. Select the Round Duct Reducing Elbow: 18
5. Select OK and the reducing elbow is placed. This works with all shapes and sizes of duct in AutoCAD MEP 2012. Another way to connect duct that isn t aligned is to use the new offset transition feature. This places a single fitting that can also transition between different sizes and shapes. 1. For the offset transition, return to the top view. Zoom to the west corridor, and locate the two disconnected ducts: 2. From the Home tab, select the duct fitting flyout pick the duct transition utility: 3. Pick the two ends of the duct the program will add the transition, based on the duct routing preference settings: 19
Note: if you don t get a transition, go to the Manage tab under the style manager, select HVAC Duct Routing Preferences: 4. Select Standard then check the fitting settings on preferences. Make sure you have a fitting selecting for any part that lists offset. You ll need to do this if you started the drawing in an earlier release, or didn t have this set for your template. 20
These are just a few of the ways to create custom layouts so you need to practice! And if you make a mistake, don t forget one of my other favorite commands UNDO! Duct Sizing Methods A new feature for this release of AutoCAD MEP relates a drawing s duct engineering units. The Drawing Setup dialog, which normally controls items such as layering standards, units, scale and object display, includes a tab for HVAC. You can access this tool by using the application menu pick drawing utilities, and then drawing setup. Pick the HVAC tab. 1. There are three items you can now control. The first is air flow units. From here, you have several options Cubic feet per second Cubic feet per minute Gallons us per second Gallons us per minute And Gallons us per hour These are a measurement of air flowing through a duct system. 21 2. Friction units measure in two forms Inches of water per 100 feet Inches of mercury per 100 feet
These options are part of a loss factor calculation, for friction loss in a duct. 3. Velocity units set three options: Feet per second Feet per minute Miles per hour This sets the units of measurement for airflow in the duct. Each of these settings help the user that is leveraging the duct sizing tools to control the calculation method. The settings should be made in your MEP template, that is used to create your constructs or base plans, but can be adjusted as needed once the drawing is created. When a project is being completed in metric, then default metric values would be listed as the options. A few extra tips for sizing duct 1. Make sure that all ducts are connected use the solution tips setting located on the view tab. Make sure this is turned on: When a duct isn t properly connected, you ll see the tip: 22
HVAC in AutoCAD MEP: New and Improved Duct can t be properly sized with open connections, so solve these before sizing duct. 2. Make sure that all end of line components have airflow set for air terminals, select one, and then right click. Pick the MvPart Modify tool on the pop-up menu, and select the flow tab on the dialog: If flow is set to 0, then the duct can t be sized. Change this value to the correct flow rate for the room. 23
3. Another tip is to check the flow direction go back to the view tab, and turn on the Show Flow feature: The flow arrows will appear on the duct to change the flow direction, pick the duct. Right click and pick the reverse segment tool: This will correct the flow direction. 24
HVAC in AutoCAD MEP: New and Improved 4. Finally, you can export the duct systems out to external applications, such as Trane s Variduct design tool. To do this, go to the Analyze tab. Pick the export ductxml tool: 5. From the dialog, set the location of the exported XML file. Next, use select object, and pick the VAV box in the north corridor. Once it s selected, you can set the system type,, and then press start. 6. The dialog monitors the progress, and you can view the event log for errors the same behavior as the gbxml export feature. After using the external application to size the duct, you can re-import the settings, and the duct in the system will be adjusted as sized. 25
HVAC in AutoCAD MEP: New and Improved Creating Parametric Multi-view Parts For our last section, the Parametric Part Wizard has been in a few releases it continues to get improvements and more parts. Making parts in AutoCAD MEP with the Content Builder can be cumbersome and sometimes, you just need to make a quick fitting or part. AutoCAD MEP includes this tool, which leverages the power of parameters and part templates to help you create a part fast. Let s take a look at how this works, and make a new air terminal. 1. Start the utility from the Home tab pick Tools, and then pick the Parametric Part Wizard:. The Wizard creates and stores the parts in your default catalogs, so you can move them around to your own custom catalogs, or leave them in the default locations but I ll make mine in the default first, and then move them so I don t have to worry about updates. 26
2. From the dialog, start by checking the part domain you can create duct, multi-view part and pipe components: 3. Select Duct from here, you can add transitions, crosses, elbows, takeoffs and tees. 4. Select Pipe from here, you can add connectors, couplings, crosses, transitions, elbows, tees and wyes. 27
5. Select Multi-view parts from here you can add air terminals, air handling units, VAV boxes, pumps, valves, fans, boilers, chillers, tanks, water heaters, cooling towers, and heat pumps. 28
HVAC in AutoCAD MEP: New and Improved 6. Select the Air Terminal for the part template, select the Round Neck template.. 7. Type in Round Neck Air Terminal for the name and description. These are required to create the part. 8. For the D1 duct connector values, add 6, 8, 10 and 12. 9. For the H Height values, add 6 and 8. 10. For the L and W values, addd 24 for each. Since these are parameters, you only have to enter the data once the wizard will create all of the sizes and versions for you. 11. Select OK and the add multi-view part dialog will open: 29
HVAC in AutoCAD MEP: New and Improved 12. The part is added to your multi-view part catalog already and 8 different diffusers are already defined! And that s all there is to it so if you want to create simple parts, use the parametric part wizard to make them and add them to that catalog so you can use them in any drawing or project. Conclusion AutoCAD MEP 2012 is even more powerful than before, and can keep up with any other BIM application. Being based on AutoCAD means that you don t have to move to Revit until you re ready, so take advantage of the sweet features and get more out of your models! For a side note, you can learn more about AutoCAD MEP 2012 by visiting 4D Technologies CADLearning site. I was lucky enough to be selected to author this year s edition, and produced over 150 beginner, intermediate and advanced training videos for this application. For more information, i visit www.cadlearning.com today. Have a great AU 2011 David B. 30