Grasshopper

algorithmic modeling for Rhino

0 | Ladybug
1 | AnalyzeWeatherData
2 | VisualizeWeatherData
3 | EnvironmentalAnalysis
4 | Renewables
5 | Extra
6 | Developers
7 | WIP

Comfort Shade Benefit Evaluator

Component Index > Ladybug > 3 | EnvironmentalAnalysis > Comfort Shade Benefit Evaluator

This is a component for visualizing the desirability of shade in terms of comfort temperature by using solar vectors, a series of hourly temperatures (usually outdoor temperatures), and an assumed balance temperature. The balance temperature represents the median temperture that people find comfortable, which can vary from climate to climate but is usually somewhere around 20C.
Solar vectors for hours when the temperature is above the balance point contribute positively to shade desirability while solar vectors for hours when the temperature is below the balance point contribute negatively.
The component outputs a colored mesh of the shade illustrating the net effect of shading each mesh face. A higher saturation of blue indicates that shading the cell is very desirable. A higher saturation of red indicates that shading the cell is harmful (blocking more winter sun than summer sun). Desaturated cells indicate that shading the cell will have relatively little effect on outdoor comfort or building performance.
The units for shade desirability are net temperture degree-days helped per unit area of shade if the test cell is blue. If the test cell is red, the units are net heating degree-days harmed per unit area of shade.
The method used by this component is based off of the Shaderade method developed by Christoph Reinhart, Jon Sargent, Jeffrey Niemasz. This component uses Shaderade's method for evaluating shade and window geometry in terms of solar vectors but substitutes Shaderade's energy simulation for an evaluation of heating and temperture degree-days about a balance temperature.
A special thanks goes to them and their research. A paper detailing the Shaderade method is available at:
http://web.mit.edu/tito_/www/Publications/BS2011_Shaderade.pdf
The heating/temperture degree-day calculation used here works by first getting the percentage of sun blocked by the test cell for each hour of the year using the Shaderade method. Next, this percentage for each hour is multiplied by the temperature above or below the balance point for each hour to get a "degree-hour" for each hour of the year for a cell. Then, all the temperture-degree hours (above the balance point) and heating degree-hours (below the balance point) are summed to give the total heating or temperture degree-hours helped or harmed respectively. This number is divided by 24 hours of a day to give degree-days. These degree days are normalized by the area of the cell to make the metric consistent across cells of different area. Lastly, the negative heating degree-days are added to the positive temperture degree-days to give a net effect for the cell.

Inputs

NameIDDescriptionType
_location_locationThe location output from the importEPW or constructLocation component. This is essentially a list of text summarizing a location on the earth.Goo
_temperatures_temperaturesA stream of 8760 temperature values (including a header) representing the temperature at each hour of the year that will be used to evaluate shade benefit. This can be the dryBulbTemperature from the 'Import EPW' component, the univeralThermalClimateIndex (UTCI) output from the 'Outdoor Comfort Calculator' component, or the standardEffectiveTemperature (SET) output from the 'PMV Comfort Calculator' component. If you are using this component to evaluate shade for a passive building with no heating/cooling, this input can also be the indoor temperature of the zone to be shaded.Goo
balanceTemperature_balanceTemperature_An estimated balance temperature representing median temperture that people find comfortable, which can vary from climate to climate. The default is set to 17.5C, which is the median outdoor comfort temperature (UTCI) that defines the conditions of no thermal stress (9 < UTCI <26).Goo
temperatureOffest_temperatureOffest_An number represeting the offset from the balanceTemperature_ in degrees Celcius at which point the shade importance begins to have an effect. The default is set to 8.5 C, which is the range of outdoor comfort temperature (UTCI) that defines the conditions of no thermal stress (9 < UTCI <26).Goo
========================...Goo
_testShades_testShadesA Brep representing the shade to be evaluated for its benefit.Goo
_testRegion_testRegionA brep representing an outdoor area for which shading is being considered or the window of a building that would be affected by the shade. Note that only breps with a single surface are supported now and volumetric breps will be included at a later point.Goo
gridSize_gridSize_The length of each of the shade's test cells in model units. Please note that, as this value gets lower, simulation times will increase exponentially even though this will give a higher resolution of shade benefit.Goo
context_context_Script variable ShadeBenefitGoo
========================Script variable Shade BenefitGoo
north_north_Input a vector to be used as a true North direction for the sun path or a number between 0 and 360 that represents the degrees off from the y-axis to make North. The default North direction is set to the Y-axis (0 degrees).Goo
skyResolution_skyResolution_An interger equal to 0 or above to set the number of times that the tergenza sky patches are split. A higher number will ensure a greater accuracy but will take longer. At a sky resolution of 4, each hour's temperature is essentially matched with an individual sun vector for that hour. At a resolution of 5, a sun vector is produced for every half-hour, at 6, every quarter hour, and so on. The default is set to 4, which should be high enough of a resolution to produce a meaningful reault in all cases.Goo
delNonIntersect_delNonIntersect_Set to "True" to delete mesh cells with no intersection with sun vectors. Mesh cells where shading will have little effect because an equal amount of warm and cool temperature vectors will still be left in white.Goo
legendPar_legendPar_Legend parameters that can be used to re-color the shade, change the high and low boundary, or sync multiple evaluated shades with the same colors and legend parameters.Goo
parallel_parallel_Set to "True" to run the simulation with multiple cores. This can increase the speed of the calculation substantially and is recommended if you are not running other big or important processes.Goo
bakeIt_bakeIt_An integer that tells the component if/how to bake the bojects in the Rhino scene. The default is set to 0. Choose from the following options: 0 (or False) - No geometry will be baked into the Rhino scene (this is the default). 1 (or True) - The geometry will be baked into the Rhino scene as a colored hatch and Rhino text objects, which facilitates easy export to PDF or vector-editing programs. 2 - The geometry will be baked into the Rhino scene as colored meshes, which is useful for recording the results of paramteric runs as light Rhino geometry.Goo
_runIt_runItSet to 'True' to run the simulation.Goo

Outputs

NameIDDescriptionType
outreadMe!...String
====================...Goo
sunVectorssunVectorsThe sun vectors that were used to evaluate the shade (note that these will increase as the sky desnity increases).Goo
regionTestPtsregionTestPtsPoints across the test region surface from which sun vectors will be projectedGoo
shadeMeshshadeMeshA colored mesh of the _testShades showing where shading is helpful (in satuated blue), harmful (in saturated red), or does not make much of a difference (white or desaturated colors).Goo
legendlegendLegend showing the numeric values of degree-days that correspond to the colors in the shade mesh.Goo
legendBasePointlegendBasePointScript variable Shade BenefitGoo
====================Script variable Shade BenefitGoo
shadeHelpfulnessshadeHelpfulnessThe cumulative temperture degree-days/square Rhino model unit helped by shading the given cell. (C-day/m2)*if your model units are meters.Goo
shadeHarmfulnessshadeHarmfulnessThe cumulative heating degree-days/square Rhino model unit harmed by shading the given cell. (C-day/m2)*if your model units are meters. Note that these values are all negative due to the fact that the shade is harmful.Goo
shadeNetEffectshadeNetEffectThe sum of the helpfulness and harmfulness for each cell. This will be negative if shading the cell has a net harmful effect and positive if the shade has a net helpful effect.Goo

© 2018   Created by Robin Rodricks and Andrew Heumann.   Hosted by

Badges  |  Report an Issue  |  Terms of Service