# Tutorial: Thermal Comfort Parameters for HVAC Simulations **URL:** \ **Category:** Post-processing\ **Created:** [November 4, 2016, 10:40am UTC](https://www.simscale.com/forum/t/tutorial-thermal-comfort-parameters-for-hvac-simulations/49750 "2016-11-04T10:40:16Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Ali\_Arafat](https://www.simscale.com/forum/user_avatar/www.simscale.com/ali_arafat/32/153_2.png) [@Ali\_Arafat](https://www.simscale.com/forum/u/Ali_Arafat)\ **Post date:** [November 4, 2016, 10:40am UTC](https://www.simscale.com/forum/t/tutorial-thermal-comfort-parameters-for-hvac-simulations/49750/1 "2016-11-04T10:40:16Z")
## Tutorial: Post-processing Thermal Comfort Parameters for HVAC Simulations This tutorial details how to post-process the HVAC simulation results for calculation of the ‘**Effective Draft Temperature (EDT)**’ and the ‘**Air diffusion performance index (ADPI)**’ in **Paraview** using a sample case of Air-Conditioning of a Hall building. ### Description of Parameters: **Effective Draft Temperature (EDT)** The Effective Draft Temperature provides a quantifiable indication of comfort at a discrete point in a space by combining the physiological effects of air temperature and air motion on a human body. A point is considered comfortable if the results of Equation below are between –3°F and +2°F, and the measured velocity at the point is less than 70 fpm (0.36 m/s). ``` EDT = (Tx – Tc) – 0.07(Vx – 30) ``` where EDT = Effective Draft Temperature, °F Tx = local airstream dry-bulb temperature, °F Tc = average room dry temperature, (control) °F Vx = local airstream centerline velocity, fpm **If the inputs are in SI units (Temp in Kelvin, Velocity in m/s), the formulation becomes:** ``` EDT =[1.8(T - Tc) -0.07( 196.85*Vx - 30)] ``` . **Air diffusion performance index (ADPI)** **ADPI** is a single number that quantifies the overall comfort of a space when in cooling. \_ADPI is the percentage of points in a space\* where the EDT is between –3°F and +2°F \_ A high percentage of people have been found to be comfortable in cooling applications for office-type occupations where these conditions are met. High ADPI values generally correlate to high space thermal comfort levels with the maximum obtainable value of 1 or 100%. - ADPI is defined in a zone between 0.1 m and ~2 m from the floor and 0.3 m from interior walls (ASHRAE Standard 55, 2010). . ### Step-by-Step: You can import this sample project by right-clicking and opening in new tab: **Import Project Link** : [SimScale Login](https://www.simscale.com/workbench?publiclink=4904a243-b339-491c-bc76-2ed4adb94c53) - Start the ParaView software and click on the ‘Open file’ icon as shown. - Select the ‘ **case.foam** ’ and click OK. ![](https://www.simscale.com/forum/uploads/default/original/2X/3/30500417020769beadcad68f00109b9f05c05895.png) - Now in the left panel, click on the green ‘ **Apply** ’ button under properties section. ![](https://www.simscale.com/forum/uploads/default/original/2X/9/9672212b9b2bc857ac7b30fa3d0389811bd9d4ae.png) - Then to goto the last saved solution, click on the ‘ **Last Frame** ’ icon from the top tool bar (see #1 in figure) - and change the field variable to **temperature ‘T’** from the drop down list (see #2 in figure). ![](https://www.simscale.com/forum/uploads/default/original/2X/1/12c0a48fca292040b64cef1c6f026a3481b527bc.png) - Now, we will first calculate ‘ **Tc: average room dry temperature** ’. For this we have to integrate the temperature over the domain and divide it by the room volume. In ParaView we will use ‘Filters’ to do this. - So, on the top menu bar Click on **Filters \> Alphabetical \> Integrate Variables** to add integration filter on the complete volume mesh domain. ![4eea8e7443723e9b2a6e40c896ba998d43bcb6e7](https://www.simscale.com/forum/uploads/default/original/3X/6/c/6ca63475ae96dc7f29cd8c4e05e6816b4385e778.jpeg) - and click the green ‘ **Apply** ’ button in the left panel. ![](https://www.simscale.com/forum/uploads/default/original/2X/4/4aaf91b7975f01dcb65c5745e299f4941f38486f.png) - This will open a spreadsheet table in the viewer as shown. - Now, in the left panel under properties, change the ‘ **Field Association** ’ type to " **Cell Data**" - The value under **‘T’** is now the integrated temperature. - **You can now calculate Tc (avg room temp) by dividing this integrated T by the volume. i.e 54702.5 / 185.12 = 295.4975 Kelvin.** ![](https://www.simscale.com/forum/uploads/default/original/2X/9/972a651a407b36cdc9dc725bccee16e804715ef5.png) - Now click back on the **‘case.foam’** in the **Pipeline Browser** - and click on the **‘calculator’** icon to add a calculation filter. ![](https://www.simscale.com/forum/uploads/default/original/2X/0/068c5b1e034d38287551a598841998461900e077.png) - First, under properties change the **‘Attribute mode’ to ‘CellData’**. - then, ‘result Array name’ to **‘EDT’**. - Then copy and past the EDT formulation (repeated below) as shown. Here the Tc is already replaced with the value 295.5 computed earlier. _(1.8(T-295.5))-(0.07_((196.85\*mag(U))-30))\*\* - Lastly, click on the green ‘ **Apply** ’ button. ![](https://www.simscale.com/forum/uploads/default/original/2X/4/4aa0ebd57c1c0f08e79ce3e3fc84d38e4f8b85d7.png) - You can now change the field variable from the drop down list to **EDT**. - Next, we will **Clip** the domain for the zone of interest (see ADPI definition) by clicking on the **‘Clip’** icon in the tool bar. ![](https://www.simscale.com/forum/uploads/default/original/2X/0/071a9618bdb39c645a239a538322f8b9c0084b78.png) - Change the 2 values for Origin and Normal as shown and click Apply. ![](https://www.simscale.com/forum/uploads/default/original/2X/7/77538f5ebbcbbc13a711c35d565b2ff5bba82661.png) - Again apply a Clip filter by clicking **Clip icon** (to clip the top), enter the values as shown and click Apply. ![](https://www.simscale.com/forum/uploads/default/original/2X/a/a4979734f2985d7b10b6f6daa7976dba3608e5d6.png) - To hide the outline, uncheck the **‘Show Plane’** under properties. ![](https://www.simscale.com/forum/uploads/default/original/2X/0/05e777972b76238bdf7972d76f975555ba76ec1e.png) - Now we will calculate the volume of this zone of interest for ADPI. So, on the top menu bar Click on **Filters \> Alphabetical \> Integrate Variables** to add integration filter and click on Apply. ![31fc32aa8b11ca654154ea396c6bb70004494476](https://www.simscale.com/forum/uploads/default/original/3X/a/7/a7ca71266002d82ef7627c251afb5c4c2bb4b473.jpeg) ![](https://www.simscale.com/forum/uploads/default/original/2X/7/74e30983bfb27e103bb79c4a18c68192d4c0e26b.png) - Change the Field Association to **‘Cell Data’** and then note down the Volume of this zone from the opened spreadsheet in the viewer. **The value is 114.73** and will be the denominator for the ADPI formula. ![](https://www.simscale.com/forum/uploads/default/original/2X/4/49a01c46ab5baa9ba48c9f8c917d87015b0f7673.png) - Now to find the cells that satisfy the criteria: –3º to 2ºF for EDT we will apply a threshold. - So goto, **Filters \> Alphabetical \> Threshold** to add the filter. ![424a980d562a97b57eb1e6378a3cf72147ac6df4](https://www.simscale.com/forum/uploads/default/original/3X/e/5/e55a56d2d1c1eb9fbd57111adec503b98776bbd0.jpeg) - Change the **Scalar to ‘EDT’ , minimum to -3 and maximum to 2** , then click on Apply. ![](https://www.simscale.com/forum/uploads/default/original/2X/f/f7cce04dc6f0585245cd7d2d8aca32c5356cfee7.png) - Now make sure the field variable is selected as EDT, then click on **‘custom range icon’** as shown. - enter **range as -3 to 2.** and click Rescale to update the viewer to the threshold range. ![](https://www.simscale.com/forum/uploads/default/original/2X/d/dd51a5e9ffcc1ccbfa5801cd15e9130464c05a5f.png) - To see the threshold domain, under properties (for threshold) change **Opacity to 0.3** and **press enter**. ![](https://www.simscale.com/forum/uploads/default/original/2X/b/bcf7a2f816f9da226bcef5316eee0031c5081432.png) - Now to calculate the volume of this threshold zoone, we will add a Integration filter as before. - So goto, **Filters \> Alphabetical \> Integrate variables** , to add the filter. - Close the previous spreadsheet by clicking the cross icon ( ref #1 in figure) , then click Apply for the new filter. ![](https://www.simscale.com/forum/uploads/default/original/2X/2/2bc22885d244619bf0b5e3aff1f843c42604c1f2.png) - with the Latest filter selected, change the **Field Association to Cell Data** and note the value of the Volume of the threshold zone. **The value in this case is 112.987** - **Now to calculate ADPI: divide 112.987 by 114.73 = 0.98** ![](https://www.simscale.com/forum/uploads/default/original/2X/4/45b3d4dc5fb9efed2d12efce01a24d86c8eb5c84.png) - Further, to visualize EDT inside the domain, click on the **‘Calculator1’ filter in the Pipeline Browser** and apply a filter as follows: - So goto, **Filters \> Alphabetical \> CellDatatoPointData** to add the filter. Check the 2 options as shown and click Apply. ![](https://www.simscale.com/forum/uploads/default/original/2X/0/0db7089cff893fc243f441d1971256fe7ac10c68.png) - change the field variable to EDT point data as shown. - next we create a 2D slice of the domain by clicking the **Slice icon** as shown . ![](https://www.simscale.com/forum/uploads/default/original/2X/f/fba1a1ca5e37dd1909e31c680aad3825845fdbcc.png) - Then click Apply with the default parameters. ![](https://www.simscale.com/forum/uploads/default/original/2X/6/64f8554f39f57b145d91308380ee3fa420d12489.png) - Again, change the **field variable to EDT point data** as shown for the slice and **uncheck the ‘show plane’ option**. ![](https://www.simscale.com/forum/uploads/default/original/2X/d/dbc8bbf633c76cf7eeb6237114bc8d3a2451bd9f.png) - Lastly to view the room geometry outline, Click on **‘case.foam’** in the **pipeline browser** and click the **‘Eye’ icon** to turn on the domain. ( this could take a few seconds) - Change the field variable to **‘Solid Color’** and then under properties, **the Opacity to 0.3 and press enter**. ![](https://www.simscale.com/forum/uploads/default/original/2X/d/d10720793346571b6f773362d0f5e4d8271ea4dd.png) - You can then create further slices, by selecting the CellDatatoPointData filter entry in pipeline browser and then clicking Slice icon to see other sections. - **That is All !** ---
**Author:** ![Ali\_Arafat](https://www.simscale.com/forum/user_avatar/www.simscale.com/ali_arafat/32/153_2.png) [@Ali\_Arafat](https://www.simscale.com/forum/u/Ali_Arafat)\ **Post date:** [November 4, 2016, 10:40am UTC](https://www.simscale.com/forum/t/tutorial-thermal-comfort-parameters-for-hvac-simulations/49750/2 "2016-11-04T10:40:23Z")
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**Author:** ![Ali\_Arafat](https://www.simscale.com/forum/user_avatar/www.simscale.com/ali_arafat/32/153_2.png) [@Ali\_Arafat](https://www.simscale.com/forum/u/Ali_Arafat)\ **Post date:** [November 4, 2016, 4:01pm UTC](https://www.simscale.com/forum/t/tutorial-thermal-comfort-parameters-for-hvac-simulations/49750/3 "2016-11-04T16:01:57Z")