{"id":33301,"date":"2020-09-30T13:22:59","date_gmt":"2020-09-30T13:22:59","guid":{"rendered":"https:\/\/www.simscale.com\/?page_id=33301"},"modified":"2023-01-03T12:55:42","modified_gmt":"2023-01-03T12:55:42","slug":"validation-case-mean-age-of-fluid-in-a-room","status":"publish","type":"page","link":"https:\/\/www.simscale.com\/docs\/validation-cases\/validation-case-mean-age-of-fluid-in-a-room\/","title":{"rendered":"Validation Case: Mean Age of Air in a Room"},"content":{"rendered":"\n\n\n\n<p class=\"wp-block-paragraph\">The mean age of air in a room validation case belongs to fluid dynamics. This case aims to validate the following parameter:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The local mean age of air using the SimScale Field function<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">In this project, the local mean age of air (LMA) within a room is calculated. The SimScale results are compared to the experimental results reported by Martin et. al\\(^1\\).<\/p>\n\n\n\n<div class=\"hw-block hw-btnWrapper hw-btnWrapper--alignCenter \">\n    <a href=\"https:\/\/www.simscale.com\/workbench\/?pid=5030707188643734122&#038;mi=spec%3Af330a785-b480-4824-b3d0-db406e13b928%2Cservice%3ASIMULATION%2Cstrategy%3A2\" class=\"hw-btn    \" rel=\"noopener \" target=\"_blank\"    >\n        View Project    <\/a>\n<\/div>\n\n\n\n\n<h2 class=\"wp-block-heading\" id=\"geometry\" >Geometry<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The geometry consists of a rectangular room with one inlet and one outlet, as in Figure 1:<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><a href=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/roomdimensions.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"584\" src=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/roomdimensions.jpg\" alt=\"age of air geometry room dimensions\" class=\"wp-image-33302\" srcset=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/roomdimensions.jpg 768w, https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/roomdimensions-300x228.jpg 300w\" sizes=\"auto, (max-width: 768px) 100vw, 768px\" \/><\/a><figcaption class=\"wp-element-caption\">Figure 1: Dimensions of the room for the age of air validation study<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">The center points of the inlet and outlet are placed at y = 1.8 meters. Details of the room dimensions are provided in Table 1:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td><strong>Part<\/strong><\/td><td><strong>Length in x-direction \\([m]\\)<\/strong><\/td><td><strong>Length in y-direction \\([m]\\)<\/strong><\/td><td><strong>Length in z-direction \\([m]\\)<\/strong><\/td><\/tr><tr><td>Inlet<\/td><td>1.92<\/td><td>0.30<\/td><td>0.20<\/td><\/tr><tr><td>Outlet<\/td><td>0.20<\/td><td>0.30<\/td><td>1.92<\/td><\/tr><tr><td>Room<\/td><td>4.20<\/td><td>3.60<\/td><td>3.00<\/td><\/tr><\/tbody><\/table><figcaption class=\"wp-element-caption\">Table 1: Dimensions of the sections of the room<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">In the study by Martin et. Al \\(^1\\), the outlet is described to be &#8220;on the ceiling, close to the east wall (opposite to the air supply)&#8221;, however, no exact placement is given. Based on the description and the schematics of the experimental setup, a gap of 0.1 meters is assumed between the outlet and the wall opposite to the air supply:<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"651\" height=\"381\" src=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/outlet-highlight.jpg\" alt=\"outlet placement room validation\" class=\"wp-image-33303\" srcset=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/outlet-highlight.jpg 651w, https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/outlet-highlight-300x176.jpg 300w\" sizes=\"auto, (max-width: 651px) 100vw, 651px\" \/><figcaption class=\"wp-element-caption\">Figure 2: Placement of the outlet, based on the schematics of the reference study<\/figcaption><\/figure>\n<\/div>\n\n\n<div class=\"hw-block hw-note hw-note--info hw-note\">\n    <div class=\"hw-note__title\">\n        <p class=\"hw-note__titleText\"><i class=\"fa fa-exclamation-circle\" aria-hidden=\"true\"><\/i>Note<\/p>\n    <\/div>\n    <div class=\"hw-note__body\">\n        <p>By extruding the inlet and outlet sufficiently, we can allow the flow field to develop in these sections. In this case study, the inlet and outlet are extruded by a length equal to 8 times their hydraulic diameter \\(D_h\\).\r\n<br>\r\n$$D_h = \\frac {4A}{P} \\tag{1}$$\r\n<br>\r\nIn the formula above, \\(A\\) is the cross-section area and \\(P\\) is the wetted perimeter. In our case, the hydraulic diameter for the inlet and outlet is 0.24 meters.<\/p>\n    <\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"analysis-type-and-mesh\" >Analysis Type and Mesh<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Tool Type<\/strong>: <a href=\"https:\/\/www.openfoam.com\/\" target=\"_blank\" rel=\"noreferrer noopener\">OpenFOAM\u00ae<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Analysis Type<\/strong>: <a href=\"https:\/\/www.simscale.com\/docs\/analysis-types\/incompressible-fluid-flow-analysis\/\">Incompressible<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Turbulence Model<\/strong>: <a href=\"https:\/\/www.simscale.com\/docs\/simulation-setup\/global-settings\/k-omega-sst\/\">k-omega SST<\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Mesh and Element Types<\/strong>: This validation case uses a total of 3 meshes to perform a mesh independence study. All meshes were created in SimScale with the <a href=\"https:\/\/www.simscale.com\/docs\/simulation-setup\/meshing\/standard\/\">Standard mesher<\/a> algorithm. In Table 2, an overview of them is presented:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td><strong>Mesh<\/strong><\/td><td><strong>Mesh Type<\/strong><\/td><td><strong>Cells<\/strong><\/td><td><strong>Element Type<\/strong><\/td><\/tr><tr><td>Coarse<\/td><td>Standard<\/td><td>192199<\/td><td>3D tetrahedral\/hexahedral<\/td><\/tr><tr><td>Moderate<\/td><td>Standard<\/td><td>538610<\/td><td>3D tetrahedral\/hexahedral<\/td><\/tr><tr><td>Fine<\/td><td>Standard<\/td><td>2009591<\/td><td>3D tetrahedral\/hexahedral<\/td><\/tr><\/tbody><\/table><figcaption class=\"wp-element-caption\">Table 2: Summary of the meshes used for the independence study <\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Figure 3 highlights the discretization of the inlet, obtained with the fine standard mesh.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><a href=\"https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Fine-Mesh.png\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"540\" src=\"https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Fine-Mesh-1024x540.png\" alt=\"Mean Age of Air Fine Mesh\" class=\"wp-image-59633\" srcset=\"https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Fine-Mesh-1024x540.png 1024w, https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Fine-Mesh-300x158.png 300w, https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Fine-Mesh-768x405.png 768w, https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Fine-Mesh.png 1364w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/a><figcaption class=\"wp-element-caption\">Figure 3: Fine standard mesh created in SimScale, highlighting the discretization of the inlet<\/figcaption><\/figure>\n<\/div>\n\n\n<h2 class=\"wp-block-heading\" id=\"simulation-setup\" >Simulation Setup<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Material<\/strong>:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Air\n<ul class=\"wp-block-list\">\n<li><em>Viscosity model<\/em>: Newtonian<\/li>\n\n\n\n<li>\\((\\nu)\\) <em>Kinematic viscosity<\/em>: 1.5295e-5 \\(m^2\/s\\)<\/li>\n\n\n\n<li>\\((\\rho)\\) <em>Density<\/em>: 1.196 \\(kg\/m^3\\)<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Boundary Conditions<\/strong>:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Figure 4 shows the assignment of the boundary conditions and the corresponding surfaces:<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><a href=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/boundary-conditions-1.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"706\" height=\"565\" src=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/boundary-conditions-1.jpg\" alt=\"age of air validation case boundary condition overview\" class=\"wp-image-33358\" srcset=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/boundary-conditions-1.jpg 706w, https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/boundary-conditions-1-300x240.jpg 300w\" sizes=\"auto, (max-width: 706px) 100vw, 706px\" \/><\/a><figcaption class=\"wp-element-caption\">Figure 4: Overview of the boundary conditions used in the mean age of air validation case<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">The exact configuration of the boundary conditions is given in the table below:<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td><strong>Boundary<\/strong><\/td><td><strong>Boundary Type<\/strong><\/td><td><strong>Velocity \\([m\/s]\\)<\/strong><\/td><td><strong>Pressure \\([Pa]\\)<\/strong><\/td><\/tr><tr><td>Inlet<\/td><td>Velocity Inlet<\/td><td>1.68 in the x-direction<\/td><td>Zero gradient<\/td><\/tr><tr><td>Outlet<\/td><td>Pressure Outlet<\/td><td>Zero Gradient<\/td><td>Fixed at 0<\/td><\/tr><tr><td>Walls<\/td><td>Automatic Wall<\/td><td>No-Slip<\/td><td>Zero gradient<\/td><\/tr><\/tbody><\/table><figcaption class=\"wp-element-caption\">Table 3: Summary of the boundary conditions for the present validation case<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Model:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\\((Sc_{t})\\) <em>Turb. Schmidt number<\/em> = 1<\/li>\n\n\n\n<li><em>Diffusion coefficients<\/em> = 1e-9 \\(m^2\/s\\)<\/li>\n<\/ul>\n\n\n\n<div class=\"hw-block hw-note hw-note--info hw-note\">\n    <div class=\"hw-note__title\">\n        <p class=\"hw-note__titleText\"><i class=\"fa fa-exclamation-circle\" aria-hidden=\"true\"><\/i>Note<\/p>\n    <\/div>\n    <div class=\"hw-note__body\">\n        <p>The <i>diffusion coefficient<\/i> is purposedly set to a small number. The objective is to prevent the scalar from spreading in the domain via diffusion effects, which would reduce the accuracy of the local mean age of air.<\/p>\n    <\/div>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Mean age of air calculation<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">To track the LMA within the room the in-built SimScale field function is used. To activate this feature extend <em>Result control<\/em> and create a new <strong>&#8216;Mean age of fluid&#8217;<\/strong> field function by clicking on the plus icon. The diffusion coefficients and the turbulent Schmidt number are set as described before. <\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><a href=\"https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Field-Function-Set-up.png\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"546\" src=\"https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Field-Function-Set-up-1024x546.png\" alt=\"\" class=\"wp-image-59634\" srcset=\"https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Field-Function-Set-up-1024x546.png 1024w, https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Field-Function-Set-up-300x160.png 300w, https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Field-Function-Set-up-768x410.png 768w, https:\/\/frontend-assets.simscale.com\/media\/2022\/11\/Mean-Age-of-Air-Field-Function-Set-up.png 1352w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/a><figcaption class=\"wp-element-caption\">Figure 5: Volumetric passive scalar source for a mean age of fluid simulation<\/figcaption><\/figure>\n<\/div>\n\n\n<div class=\"hw-block hw-note hw-note--info hw-note\">\n    <div class=\"hw-note__title\">\n        <p class=\"hw-note__titleText\"><i class=\"fa fa-exclamation-circle\" aria-hidden=\"true\"><\/i>Mean age of Fluid Field Function<\/p>\n    <\/div>\n    <div class=\"hw-note__body\">\n        <p>You can find out moe information about the Mean age of Fluid Field Function <a href=\"https:\/\/www.simscale.com\/docs\/simulation-setup\/result-control\/field-calculations\/#mean-age-of-fluid\">here<\/a>.\r\n<\/p>\n    <\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"experimental-results\" >Experimental Results<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">In the experimental tests, Martin et. al\\(^1\\) first filled the test room with tracer gas and waited to obtain an even distribution. Afterward, fresh air is released at the inlet, which causes the tracer gas concentration to decay.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A series of gas monitors are used to measure how the concentration of the tracer gas evolves with time. The resulting LMA is obtained by calculating the area under the concentration <em>versus<\/em> time curve.<\/p>\n\n\n\n<div class=\"hw-block hw-note hw-note--info hw-note\">\n    <div class=\"hw-note__title\">\n        <p class=\"hw-note__titleText\"><i class=\"fa fa-exclamation-circle\" aria-hidden=\"true\"><\/i>Note<\/p>\n    <\/div>\n    <div class=\"hw-note__body\">\n        <p>The theoretical value for the mean age of fluid at the outlet is given by Equation 2:\r\n<br>\r\n$$Mean\\ age\\ of\\ fluid = \\frac {V}{Q} \\tag{2}$$\r\n<br>\r\nWhere \\(V\\) is the volume of the test environment and \\(Q\\) is the volumetric flow rate at the inlet. Using the data from the experimental setup in the equation above, we obtain 450 seconds.<br>\r\n<br>\r\n<\/p>\n    <\/div>\n<\/div>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"result-comparison\" >Result Comparison<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The numerical simulation results for the LMA are compared with experimental data presented by Martin et. al\\(^1\\). The authors use a dimensionless form of the LMA to present their results. In the present validation case, the same methodology is used:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">$$\\overline{\\theta} = \\frac{\\theta}{V\/Q} \\tag{3}$$<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Where:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\\(\\overline{\\theta}\\) is the local mean age of air (dimensionless)<\/li>\n\n\n\n<li>\\(\\theta\\) is the local mean age of air, in seconds.<\/li>\n\n\n\n<li>\\(V\\) is the volume of the passive scalar source, in \\(m^3\\)<\/li>\n\n\n\n<li>\\(Q\\) is the volumetric flow rate at the inlet, in \\(m^3\/s\\)<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">In addition, the results by Martin et. al \\(^1\\) are adjusted so that the dimensionless LMA of 1 is corresponding to an LMA of 538 seconds. The values obtained by SimScale have been adjusted accordingly. A comparison of the dimensionless LMA obtained experimentally and with SimScale is presented. The results are assessed on a series of points over three lines, placed&nbsp;on the symmetry plane of the geometry (y = 1.8 meters). The lines are distant 1.13 \\(m\\), 2.2 \\(m\\), and 3.2 \\(m\\) from the inlet, and the points are spread on each line with a distance of 0.1 meters. The placement of the lines can be seen below:<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><a href=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/results-assessment.jpg\"><img loading=\"lazy\" decoding=\"async\" width=\"708\" height=\"478\" src=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/results-assessment.jpg\" alt=\"mean age of air obtaining results\" class=\"wp-image-33360\" srcset=\"https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/results-assessment.jpg 708w, https:\/\/frontend-assets.simscale.com\/media\/2020\/09\/results-assessment-300x203.jpg 300w\" sizes=\"auto, (max-width: 708px) 100vw, 708px\" \/><\/a><figcaption class=\"wp-element-caption\">Figure 6: The red dashed lines, placed on the XZ symmetry plane, indicate where the dimensionless local mean age of air is being compared to the experimental data.<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">To perform a mesh independence study, the results from the three meshes created in SimScale were compared. The results for all three meshes were found to be mesh independent. Figure 7 shows the results over the line located 1.13 meters away from the inlet.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><a href=\"https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X1.3m-and-Y1.8m.png\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"371\" src=\"https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X1.3m-and-Y1.8m.png\" alt=\"mean age of fluid X=1.3m and Y=1.8m\" class=\"wp-image-62738\" srcset=\"https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X1.3m-and-Y1.8m.png 600w, https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X1.3m-and-Y1.8m-300x186.png 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/a><figcaption class=\"wp-element-caption\">Figure 7: Comparison between the experimental data and results from different meshes in SimScale<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">In the remaining figures, you will find the comparison between the experimental data and the fine mesh results:<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><a href=\"https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X-2.2m-and-Y1.8m.png\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"371\" src=\"https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X-2.2m-and-Y1.8m.png\" alt=\"mean age of fluid X = 2.2m and Y=1.8m\" class=\"wp-image-62737\" srcset=\"https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X-2.2m-and-Y1.8m.png 600w, https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X-2.2m-and-Y1.8m-300x186.png 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/a><figcaption class=\"wp-element-caption\">Figure 8: Comparison of the mean age of fluid over a line 2.2 meters away from the inlet<\/figcaption><\/figure>\n<\/div>\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><a href=\"https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X3.2m-and-Y1.8m.png\"><img loading=\"lazy\" decoding=\"async\" width=\"600\" height=\"371\" src=\"https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X3.2m-and-Y1.8m.png\" alt=\"mean age of fluid X=3.2m and Y=1.8m\" class=\"wp-image-62736\" srcset=\"https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X3.2m-and-Y1.8m.png 600w, https:\/\/frontend-assets.simscale.com\/media\/2023\/01\/X3.2m-and-Y1.8m-300x186.png 300w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/a><figcaption class=\"wp-element-caption\">Figure 9: Comparison of the mean age of fluid over a line 3.2 meters away from the inlet<\/figcaption><\/figure>\n<\/div>\n\n\n<p class=\"wp-block-paragraph\">In all cases, the SimScale results show the same trends and range as the experimental values obtained by Martin et. al\\(^1\\).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The figure below shows the mean age of fluid on the symmetry plane of the geometry. The fresh air coming from the inlet quickly mixes with the old air in the room. The mean age of air at the outlet for the fine mesh was found to be 451.8 seconds.<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large\"><a href=\"https:\/\/frontend-assets.simscale.com\/media\/2022\/12\/mean-age-of-fluid-result-Fine-mesh-slice.png\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"864\" src=\"https:\/\/frontend-assets.simscale.com\/media\/2022\/12\/mean-age-of-fluid-result-Fine-mesh-slice-1024x864.png\" alt=\"mean age of fluid result Fine mesh slice\" class=\"wp-image-60149\" srcset=\"https:\/\/frontend-assets.simscale.com\/media\/2022\/12\/mean-age-of-fluid-result-Fine-mesh-slice-1024x864.png 1024w, https:\/\/frontend-assets.simscale.com\/media\/2022\/12\/mean-age-of-fluid-result-Fine-mesh-slice-300x253.png 300w, https:\/\/frontend-assets.simscale.com\/media\/2022\/12\/mean-age-of-fluid-result-Fine-mesh-slice-768x648.png 768w, https:\/\/frontend-assets.simscale.com\/media\/2022\/12\/mean-age-of-fluid-result-Fine-mesh-slice.png 1280w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/a><figcaption class=\"wp-element-caption\">Figure 10: Fine mesh results, showing the mean age of air on the symmetry plane<\/figcaption><\/figure>\n<\/div>\n\n\n\n<div class='hw-block hw-references hw-references'>\n    <p class='hw-references__title'>References<\/p>\n    <ul class='hw-references__list'>\n\n        <li><cite><a href=\"https:\/\/www.ibpsa.org\/proceedings\/bs2001\/bs01_0773_780.pdf\" target=\"_blank\">\u201cB. Martin, M, Cermak, J. Clarke, J. Denev, F. Drkal, \r\n M. Lain, I. Macdonald, M. Majer, P. Stankov.  Experimental and numerical study of local mean age of air. 7th International IBPSA Conference, 2011, Rio de Janeiro, Brazil.&#8221;<\/a><\/cite><\/li>\n    <\/ul>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>The mean age of air in a room validation case belongs to fluid dynamics. This case aims to validate the following parameter:...","protected":false},"author":114,"featured_media":0,"parent":17191,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"templates\/template-documentation.php","meta":{"_acf_changed":false,"_crdt_document":"","inline_featured_image":false,"footnotes":""},"class_list":["post-33301","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.simscale.com\/wp-json\/wp\/v2\/pages\/33301","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.simscale.com\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.simscale.com\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.simscale.com\/wp-json\/wp\/v2\/users\/114"}],"replies":[{"embeddable":true,"href":"https:\/\/www.simscale.com\/wp-json\/wp\/v2\/comments?post=33301"}],"version-history":[{"count":0,"href":"https:\/\/www.simscale.com\/wp-json\/wp\/v2\/pages\/33301\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/www.simscale.com\/wp-json\/wp\/v2\/pages\/17191"}],"wp:attachment":[{"href":"https:\/\/www.simscale.com\/wp-json\/wp\/v2\/media?parent=33301"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}