looked at autodesk simulation cfd 2015 and was optimistic because it had an export plugin from revit, which i use anyway for material takeoffs and etc, but found that it did not take solar radiation into account. This was a downer because I have heard that solar radiation could effect indoor airflow - convection - as much as 50 percent at a time.
Then I searched again and found that Hyperworks, a software by altair technology can be coupled with a radiation software. So I went through the trouble of obtaining an educational license of Hyperworks. However, though some email exchange I have found that the coupling is a one-way. The radiation analysis software was used, I think, for understanding the solar loading for a SOM project called church of light.
The support guy said : "Unfortunately our coupling with Hyperworks is really a one way coupling. We can accept H coefficients from their software in RadTherm, but they will not read in our wall temps. That said, it still can be a useful coupling in the sense that you can run the analysis in Hyperworks, send H coefficients to RadTherm, and run the analysis to better understand radiation and conduction. Most importantly, that analysis can be done for longer transient analysis, but will require much less compute time and resources."
Not only did I not understand what he means by the H coefficients, my wanting to get a CFD understanding coupled with solar radiation was again, unsatisfied. In the mean while I had to finish a presentation so I haven't had the time to try to get some result on the natural ventilation. I would probably need to look into how their solutions work before I can understand if their software would "do the job"
Thank you for letting me know about your work on this. I downloaded the Honeybee_Set EP Natural Ventilation component and made sure that it is allowed, but it does not show up in grasshopper.
You pointed out that "The component (and the corresponding equation) is mostly meant for cases where you have zones with windows that are NOT connected by an air wall (or a larger airflow network)." I wondered if you are suggesting it would be a code violation for zones to be connected by an air wall for fire safety reasons. It would be a violation I guess, like not putting an fiber insulation or some kind of smoke stop between Spandrel panels and the edge of a floor plate would be a code violation for a typical office building.
There is a project by kevin daly architects where you can see a section drawing with what seems like a cfd analysis (could be an illustration)
it was my initial visualization/simulation goals were for a facade design I am working on
1) an average air velocity across a zone at noon, for example, if a passive design strategy like this was used. for this I am guessing cfd is not entirely necessary. probably means that it could be used earlier in a design process, too. This would be more about user comfort.
2) at a later phase, like in detailing facade components, if airflow is indeed as expected for a zone that is connected to an air wall / chimney like feature (and to see if there is a proper mixing of air)
3) and a projection of energy savings, of course.
After seeing a video of simulation cfd I was optimistic, but like I said sim cfd does not take account of solar loading. I think I would probably go ahead start with one zone with sim cfd first, try three zones stacked on top of each other, then try hyperworks and try to factor in solar radiation.
For analyzing multiple zones on different levels, being able to add a chimney would be especially useful, I think. Having said that, I don't have a lot of experience of using honeybee except for the daylight component so it would take some time for me to understand the components.
I hope some of the information here is useful for you. after all, both sim cfd and hyperworks are commercial softwares and somewhat different than the e plus project you are working on, I guess but still trying to address a similar problem.
so.. in cased you missed it I was asking I downloaded the Honeybee_Set EP Natural Ventilation component and made sure that it is allowed and placed in the user object foler, but it does not show up in grasshopper. what could be the reason?
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rmation?" I know that this can already be accomplished using the brilliant Kangaroo plugin, but I wanted a simpler and faster (yet still accurate) single component that could replicate this unique curve using a variety of inputs: the length of the rod/wire, the width/distance between the endpoints, the height of the bend, and the tangent angle at the start. I also wanted make the unknowns (such as height if only length and width are known) easily accessible for plugging into additional components.
The resulting script, being an all-in-one solution, is somewhat unwieldy, but it could easily be broken down into smaller components (custom .gha's which I don't have the ability to code). If someone wants to tackle this, please do! I'm not an expert coder by any means, and as this was only my second time diving into Grasshopper scripting, if the script seems somewhat strange, that's probably why. I did try to comment the code pretty well though. Here's the full description:
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DESCRIPTION: This beast creates the so-called 'elastica curve', the shape a long, thin rod or wire makes when it is bent elastically (i.e. not permanently). In this case, force is assumed to only be applied horizontally (which would be in line with the rod at rest) and both ends are assumed to be pinned or hinged meaning they are free to rotate (as opposed to clamped, when the end tangent angle is fixed, usually horizontally). An interesting finding is that it doesn't matter what the material or cross-sectional area is, as long as they're uniform along the entire length. Everything makes the same shape when bent as long as it doesn't cross the threshold from elastic to plastic (permanent) deformation (I don't bother to find that limit here, but can be found if the yield stress for a material is known).
Key to the formulas used in this script are elliptic integrals, specifically K(m), the complete elliptic integral of the first kind, and E(m), the complete elliptic integral of the second kind. There was a lot of confusion over the 'm' and 'k' parameters for these functions, as some people use them interchangeably, but they are not the same. m = k^2 (thus k = Sqrt(m)). I try to use the 'm' parameter exclusively to avoid this confusion. Note that there is a unique 'm' parameter for every configuration/shape of the elastica curve.
This script tries to find that unique 'm' parameter based on the inputs. The algorithm starts with a test version of m, evaluates an expression, say 2*E(m)/K(m)-1, then compares the result to what it should be (in this case, a known width/length ratio). Iterate until the correct m is found. Once we have m, we can then calculate all of the other unknowns, then find points that lie on that curve, then interpolate those points for the actual curve. You can also use Wolfram|Alpha as I did to find the m parameter based on the equations in this script (example here: http://tiny.cc/t4tpbx for when say width=45.2 and length=67.1).
Other notes:
* This script works with negative values for width, which will creat a self-intersecting curve (as it should). The curvature of the elastica starts to break down around m=0.95 (~154°), but this script will continue to work until M_MAX, m=0.993 (~169°). If you wish to ignore self-intersecting curves, set ignoreSelfIntersecting to True
* When the only known values are length and height, it is actually possible for certain ratios of height to length to have two valid m values (thus 2 possible widths and angles). This script will return them both.
* Only the first two valid parameters (of the required ones) will be used, meaning if all four are connected (length, width or a PtB, height, and angle), this script will only use length and width (or a PtB).
* Depending on the magnitude of your inputs (say if they're really small, like if length < 10), you might have to increase the constant ROUNDTO at the bottom
REFERENCES: {1} "The elastic rod" by M.E. Pacheco Q. & E. Pina, http://www.scielo.org.mx/pdf/rmfe/v53n2/v53n2a8.pdf {2} "An experiment in nonlinear beam theory" by A. Valiente, http://www.deepdyve.com/lp/doc/I3lwnxdfGz {3} "Snap buckling, writhing and Loop formation In twisted rods" by V.G.A. GOSS, http://myweb.lsbu.ac.uk/~gossga/thesisFinal.pdf {4} "Theory of Elastic Stability" by Stephen Timoshenko, http://www.scribd.com/doc/50402462/Timoshenko-Theory-of-Elastic-Stability (start on p. 76)
INPUT: PtA - First anchor point (required) PtB - Second anchor point (optional, though 2 out of the 4--length, width, height, angle--need to be specified) [note that PtB can be the same as PtA (meaning width would be zero)] [also note that if a different width is additionally specified that's not equal to the distance between PtA and PtB, then the end point will not equal PtB anymore] Pln - Plane of the bent rod/wire, which bends up in the +y direction. The line between PtA and PtB (if specified) must be parallel to the x-axis of this plane
** 2 of the following 4 need to be specified ** Len - Length of the rod/wire, which needs to be > 0 Wid - Width between the endpoints of the curve [note: if PtB is specified in addition, and distance between PtA and PtB <> width, the end point will be relocated Ht - Height of the bent rod/wire (when negative, curve will bend downward, relative to the input plane, instead) Ang - Inner departure angle or tangent angle (in radians) at the ends of the bent rod/wire. Set up so as width approaches length (thus height approaches zero), angle approaches zero
* Following variables only needed for optional calculating of bending force, not for shape of curve. E - Young's modulus (modulus of elasticity) in GPa (=N/m^2) (material-specific. for example, 7075 aluminum is roughly 71.7 GPa) I - Second moment of area (or area moment of inertia) in m^4 (cross-section-specific. for example, a hollow rod would have I = pi * (outer_diameter^4 - inner_diameter^4) / 32 Note: E*I is also known as flexural rigidity or bending stiffness
OUTPUT: out - only for debugging messages Pts - the list of points that approximate the shape of the elastica Crv - the 3rd-degree curve interpolated from those points (with accurate start & end tangents) L - the length of the rod/wire W - the distance (width) between the endpoints of the rod/wire H - the height of the bent rod/wire A - the tangent angle at the (start) end of the rod/wire F - the force needed to hold the rod/wire in a specific shape (based on the material properties & cross-section) **be sure your units for 'I' match your units for the rest of your inputs (length, width, etc.). Also note that the critical buckling load (force) that makes the rod/wire start to bend can be found at height=0
THANKS TO: Mårten Nettelbladt (thegeometryofbending.blogspot.com) Daniel Piker (Kangaroo plugin) David Rutten (Grasshopper guru) Euler & Bernoulli (the O.G.'s)
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Edit: More on the math behind this here.
Cheers,
Will
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Added by Will McElwain at 4:08pm on February 26, 2014
doing this with the current tools or a bit of scripting since the Flickr API allows you to make requests in a REST format, but utilizing the Flickr.net API library makes it much simpler.
First and foremost, you need a Flickr API key...do you have one of those?
A great way to get to know the Flickr API is with the API Explorer. Here is a link to the page for the flickr.photos.search method explorer: http://www.flickr.com/services/api/explore/flickr.photos.search
The cool thing about this page is that it generates the REST Http call towards the bottom. So, here is what I did:
1. Grab the coordinates of the bounding box per Flickr API request:
bbox (Optional)
A comma-delimited list of 4 values defining the Bounding Box of the area that will be searched. The 4 values represent the bottom-left corner of the box and the top-right corner, minimum_longitude, minimum_latitude, maximum_longitude, maximum_latitude. Longitude has a range of -180 to 180 , latitude of -90 to 90. Defaults to -180, -90, 180, 90 if not specified. Unlike standard photo queries, geo (or bounding box) queries will only return 250 results per page. Geo queries require some sort of limiting agent in order to prevent the database from crying. This is basically like the check against "parameterless searches" for queries without a geo component. A tag, for instance, is considered a limiting agent as are user defined min_date_taken and min_date_upload parameters — If no limiting factor is passed we return only photos added in the last 12 hours (though we may extend the limit in the future).
So, I went to Google Earth, picked a city (London, UK) and dropped two pins:
This gave me two locations, which I can put into the Explorer Page next to the bbox option. Here is what I put for these two points: -0.155941,51.496768,-0.116783,51.511431
2. Check has_geo
3. In extras, type in geo
4. Make the call!
You will see a list of responses in an XML format, these responses will be from the first page. Geolocated photos are limited to 250 / page, so you will have to grab them page by page.
If you want to add more options (minimum upload date, maximum upload date, etc) you can do this as well)
The best is at the bottom, you get the full http call for this: http://api.flickr.com/services/rest/?method=flickr.photos.search&api_key=ffd44f601393a46e86aa3a5f8a013360&bbox=-0.155941%2C51.496768%2C-0.116783%2C51.511431&has_geo=&extras=geo&format=rest&api_sig=b42330e5d1523bd5fe60c2ad43acde99
Notice this call has some other api key, you should eventually replace this with your own.
You could copy and paste this into a browser and you will get the results with the latitude and longitude:
So this is really what you need to know to do this through GH. Since gHowl has an XML parser component that can access files on the web, you should be able to use the same http call into this component.
Eventually, we get a response, and we need to grab the lat and lon data. With gHowl we can map these to xyz coordinates, and generate the heatmap...this is just a linear mapping:
Attached are both the Rhino file and the Grasshopper file, as well as the image underlay.
I am working on a series of components that makes this more straightforward, but for now, this should get you started.
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and export the geometry out to VVVV to render it LIVE! RawRRRR. In this case, a digital audio workstation Ableton Live, a leading industrial standard in contemporary music production.
the good news is that VVVV and ableton live lite is both free.
https://www.ableton.com/en/products/live-lite/
i am not trying to use ipad as a controller for grasshoppper. I wanted to work with a timeline (similar to MAYA or Ableton or any other DAW(digital audio workstation)) inside grasshopper in an intuitive way. Currently there is no way of SEQUENCING your definition the way you want to see that i know of.
no more combersome export import workflows... i dont need hyperrealistic renderings most of the time. so much time invested in googling the right way to import, export ... mesh settings...this workflow works for some, for some not ...that workflow works if ... and still you cannot render it live nor change sequence of instruction WHILE THE VIDEO is played. and I think no one wants to present rhinoceros viewport. BUT vvvv veiwport is different. it is used for VJing and many custom audio visual installation for events, done professionally. you can see an example of how sound and visuals come together from this post, using only VVVV and ableton. http://vvvv.org/documentation/meso-amstel-pulse
I propose a NEW method. make a definition, wire it to ableton, draw in some midi notes, and see it thru VVVV LIVE while you sequence the animation the WAY YOU WANT TO BE SEEN DURING YOUR PRESENTATION FROM THE BEGINNING, make a whole set of sequences in ableton, go back change some notes in ableton and the whole sequence will change RIGHT INFRONT of you. yes, you can just add some sound anywhere in the process. or take the sound waves (sqaure, saw, whateve) or take the audio and influence geometric parameters using custom patches via vvvv. I cannot even begin to tell you how sophisticated digital audio sound design technology got last ten year.. this is just one example which isn't even that advanced in todays standard in sound design ( and the famous producers would say its not about the tools at all.) http://www.youtube.com/watch?v=Iwz32bEgV8o
I just want to point out that grasshopper shares the same interface with VVVV (1998) and maxforlive, a plug in inside ableton. audio mulch is yet another one that shares this interface of plugging components to each other and allows users to create their own sound instruments. vvvv is built based on vb, i believe.
so current wish list is ...
1) grasshopper recieves a sequence of commands from ableton DONE
thanks to sebastian's OSCglue vvvv patch and this one http://vvvv.org/contribution/vvvv-and-grasshopper-demo-with-ghowl-udp
after this is done, its a matter of trimming and splitting the incoming string.
2) translate numeric oscillation from ableton to change GH values
video below shows what the controll interface of both values (numbers) and the midi notes look like.
https://vimeo.com/19743303
3) midi note in = toggle GH component (this one could be tricky)
for this... i am thinking it would be great if ...it is possible to make "midi learn" function in grasshopper where one can DROP IN A COMPONENT LIKE GALAPAGOS OR TIMER and assign the component to a signal in, in this case a midi note. there are total 128 midi notes (http://www.midimountain.com/midi/midi_note_numbers.html) and this is only for one channel. there are infinite channels in ableton. I usually use 16.
I have already figured out a way to send string into grasshopper from ableton live. but problem is, how for grasshopper to listen, not just take it in, and interpret midi and cc value changes ( usually runs from 0 to 128) and perform certain actions.
Basically what I am trying to achieve is this : some time passes then a parameter is set to change from value 0 to 50, for example. then some time passes again, then another parameter becomes "previewed", then baked. I have seen some examples of hoopsnake but I couldn't tell that you can really control the values in a clear x and y graph where x is time and y is the value. but this woud be considered a basic feature of modulation and automation in music production. NVM, its been DONE by Mr Heumann. https://vimeo.com/39730831
4) send points, lines, surfaces and meshes back out to VVVV
5) render it using VVVV and play with enormous collection of components in VVVV..its been around since 1998 for the sake of awesomeness.
this kind of a digital operation-hardware connection is usually whats done in digital music production solutions. I did look into midi controller - grasshopper work, and I know its been done, but that has obvious limitations of not being precise. and it only takes 0 o 128. I am thinking that midi can be useful for this because then I can program very precise and complex sequence with ease from music production software like ableton live.
This is an ongoing design research for a performative exhibition due in Bochum, Germany, this January. I will post definition if I get somewhere. A good place to start for me is the nesting sliders by Monique . http://www.grasshopper3d.com/forum/topics/nesting-sliders
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as one element.
Thank you
Comment by karamba on October 7, 2014 at 11:27pm
Hello Patricio, divide the beams in such a way that each boundary vertex of the shell becomes an endpoint of a beam segment.
Best, Clemens
Comment by Llordella Patricio on October 8, 2014 at 8:30amDelete Comment
Hi Clemens,
I did what you suggested but now assemble element doesn´t work properly. Could you please tell me how to fix it? Thanks in advance, Patricio
8-10-14losa%20cadena.gh
Comment by karamba on October 8, 2014 at 11:59am
Hi Patricio, if you flatten the 'Elem'-input at the 'Assemble'-component the definition works. The triangular shell elements have linear displacement interpolations whereas the beam deflections are exact. In order to get correct results you should refine the shell mesh.
Best, Clemens
Comment by Llordella Patricio on October 9, 2014 at 8:35amDelete Comment
Hello, succeeds in creating the mesh to the slab, and built the beam segment, but when I see the deformations are not expected because the beam is deformed as the slab.
Thanks for the help
PS: maybe I'm using the program for a type of structure that is not the most appropriate, as I saw in the examples of other structures. But this type of structure is that students taught
best regards
Patricio
9-10-14%20Example%201.gh
Comment by karamba on October 9, 2014 at 10:46am
You could use the 'Mesh Edges'-component to retrieve the naked edges and turn them into beams - see attached file:91014Example1_cp.gh
Best regards,
Clemens
Comment by Llordella Patricio on October 15, 2014 at 3:41pmDelete Comment
Dear clemens
I was doing a rough estimate of the deformation, and I can not achieve the same result with Karamba. When I make a rough estimate of the result with Karamba beams and mine are very similar, I think the problem is when I connect the shell, because there are no similar results.
I sent the GH file, and an image of the calculation
The structure is concrete The result I get is 0.58cm
thank youPatricio
15-10-14%20Example.gh
Comment by karamba yesterday
Dear Patricio,
try to increase the number of shell elements. As mentioned in the manual they are linear elements. A mesh that is too coarse leads to a response which is stiffer than the real structure.
Best,
Clemens
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n be obtained for curved NURBS surfaces as well as unconventional window configurations".
And I also noticed the following information form the optional input in the runEnergySimulation component.
"meshSettings_: Optional mesh settings for your geometry from any one of the native Grasshopper mesh setting components. These will be used to change the meshing of curved surfaces before they are run through EnergyPlus (note that meshing of curved surfaces is done since Energyplus is not able to calculate heat flow through non-planar surfaces). Default Grasshopper meshing is used if nothing is input here but you may want to decrease your calculation time by changing it to Coarse or increase your curvature definition (and calculation time) by making it finer".
1) My case is an one-story, rectangular-plan large hall (40m*70m*25m) with a curved roof. The roof surface is a part of a standard sphere and the walls and floor are all planar (the each wall has one curved edge as showed in the image).
For testing, I threw the original curved roof surface into daylight and energy simulations without making customized meshings, because I assumed that it might be automatically converted to meshs by Honeybee - Am I right? As showed in the image, how can I reduce the number of meshs in a proper way? Must two connected surfaces (i.e. wall and roof) be STRICTLY/SEAMLESSLY connected or not (considering different divisions of meshs in the respective surface)? - Is a connection tolerance allowed?
2) But, when I run the annual daylight simulation for this case, it gave me a lot of warnings "oconv: warning - zero area for polygon".- is that normal? and how to avoid this? Does the daylight simulation allow "curved NURBS surfaces"?
3) Moreover, when I run an energy simulation for this case, it costed extremely long time. It was just so long that I did not even have results out of one simulation. - I guessed it might be the problem caused by the curved roof surface (or automatic meshing?), but I don't have experience of converting a curved NURBS/spheral surface into correct meshs that can be recognized by Honeybee simulations (Daylight and Energy) in a proper way.
4) The large window on the wall was generated by the "_glzRatio". But the automatically generated wall meshs around this window are just too "fine", which might largely increase simulation time. Is there a proper way to get rid of it? (Considering that the size, shape and position of the window will have large influence on the daylight distribution in the building, it is worthy to keep the size, shape and position of the window as it should be in reality).
In sum, considering all above, could your please provide me some suggestions/tutorials/links that might be helpful for dealing with "curved NURBS surfaces" in Honeybee simulations.
Thank you all in advance!
Best,
Ding
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