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Ecotect Analysis JoseAlfredo GuerreroMora 12.10.10 01.Displaying of Shadows 02.Solar Analysis, thermal comfort +lighting analysis 03.Spatial Visibility Analysis 04.Wind analysis
01.Displaying of Shadows
02 A site in ecotect is created by using the box command. A variety of buildings were created, then the heights were changed in the z axis. Next, the weather file is loaded. I loaded different cities to see how the shadows vary from city to city. Under the project tab, we specify what type of project we are going to work on by labeling the terrain (urban, exposed, rural and suburban). This is where you can name your project, describe it, add a client name, job reference, building type, location etc. Under the shadow settings, we can display shadows, and by doing this and changing the time and date we can see how the shadows vary throughout the day and months. The daily sun path and annual sun path is obtained also here.
01.Displaying of Shadows
Under the analysis tab you can see the hourly solar exposure, which lets you see the w/m2 throughout the day on a selected date. You can do the calculation on a single day, average daily, total monthly, or full monthly. The thermal analysis (graph) you can see the hourly temperatures which are values of environmental temperatures and not air temperatures. Here you can select the highlight zones and location. The graph allows you to see the outside temperature, beam solar, diffuse solar, wind speed, zone temperatures and selected zone. Here you can also analyze material cost, resource consumption, reverberation times and acoustic response. Calculating the sun path diagram: obtain a stereographic diagram, spherical diagram, equidistant diagram, BRE sun path, orthographic, waldram and tabular solar data. On all these you can overlay percentages.
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02.Solar Analysis Calculate solar analysis: step 1. What do you want to calculate? Incident solar radiation.
Solar access refers to the availability of incident solar radiation (insolation), on surfaces and points within your model. Solar radiation calculations use hourly recorded direct and diffuse radiation data from the weather file. Overshadowing and shading calculations require only the geometry of the building and its surroundings. You should check the latitude and longitude of your site and select the right weather data file before performing these calculations. step two: over what period? specific date and time.
Given the dynamic path of the Sun through the sky and changing climatic conditions, solar radiation and over- shadowing values will vary over time as well as spatially. The ‘Current Date and Time’ and ‘Current Day’ options refer to the date/time displayed in the toolbar at the top of the main application window. step three: what dates and times? Jan 1st- Dec 31st. Solar access calculations are carried out each hour between the specified start and top times for each day between the from and to dates. Values for times between hours are interpolated using the hours before and after that time. Shading and overshadowing are taken directly from the shading mask. Any times before sunrise or after sunset do not form part of the calculation and are ignored.
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02.Solar Analysis
step 4: what period-based values should be stored? cumulative values.
thermal comfort
lighting analysis A lighting analysis can show both natural and artificial light levels at specific points in your model. To consider artificial lighting, you must include LIGHT objects within your model.
Given this variation in calculated values over time, you will still need to store a single number for each object attribute or grid point. Choose between the total sum of all values, their average or the maximum value of each metric on each point or surface. step 5: what should the values be calculated for? objects in model. Values can be calculated over the analysis grid (if it is currently displayed) or for objects in the model. The analysis grid provides more flexible display options (eg: contouring) but is limited in size and aspect. Absorption and Tranmsission can only be calculated for planar surfaces, not points or the analysis grid. step 6: how to calculate overshadowing? perform detailed calculations. In order to determine which parts of the sky are visible and what percentage of each point/object is in shade at any time, ECOTECT uses a shading mask. Standard 5x5 shading masks are pre- calculated for all objects on thermal zones as part of each models’ Inter- Zonal Adjacency calculation. Using these makes the calculation much quicker. step 7: what level of shading accuracy is required? low. For this exercise is better to do low or medium. step 8: Summary.
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03.Spatial Visibility Analysis
Spatial visibility analysis: step 1: what do you want to calculate? visibility of selected objects
Visibility calculations show how much of an object can be seen from different points within the model. This is done by dividing each object up using pseudorandom samples and determining unobstructed sight lines to test points. Visibility calculations require that the analysis grid is visible in the model and covers the area of interest on site or within an enclosed space. step two: are the right objects selected?
The calculation of object visibility from each analysis grid point requires that you have at least one object in the model selected. To select the right objects, you may want to consider using items in the Select Menu to choose them by element type, zone or material. step three: what do you want to calculate? absolute sampling of grid size. surfaces are sub-divided into smaller segments and a pseudo-random point is generated in each. The number of these points visible then gives the fraction of the surface that is visible. Use the items on this page to set the absolute size of each segment. The smaller segment size the more accurate the calculation will be, but the longer it will take to complete. step four: summary. Calculate.
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04.Wind analysis
Wind analysis: First we must auto fit the grid to objects (3d air flow) and adjust the grid extents manually by moving the corners of the box to more or less fit the site better. Then under the export manager, we save in the winair 4 cfd tab. Here we create a new folder preferably in the c drive. It is important that this folder is named with only characters and no spaces. The file name must also be only characters and no spaces. This should be a winair cfd geometry file (*.GEO). In the computational fluid dynamics (analysis grid setup) select covered in z. Under blockages, change the speed to a maximum of 8 m/s, and the wind direction to for example 50.
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04.Wind analysis
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Go to analysis grid and select load cfd data. Load output file from the folder that was created in the c drive. Once calculated, you can play with the different options: show contours, grid squares, chip to minimum, show grid axis, node values, and average value. You can also change the display settings under data and scale: cell temperature, cell pressure, cell contamination, air flow rate, and flow vector.