modelHumanSensibleHeatAreaSpecific
Extends from AixLib.Obsolete.BaseClasses.ObsoleteModel (Icon for classes that are obsolete and will be removed in later versions).
Information
Overview
Model for heat output of a human according to VDI 2078 (Table A.1). The model only considers the dry heat emission and divides it into convective and radiative heat transmission.
Concept
It is possible to choose between several types of physical activity.
The heat output depends on the air temperature in the room where the activity takes place.
A schedule of the activity is also required as constant presence of people in a room is not realistic. The schedule describes the presence of only one person, and can take values from 0 to 1.
Assumptions
The surface for radiation exchange is computed from the number of persons in the room, which leads to a surface area of zero, when no one is present. In particular cases this might lead to an error as depending of the rest of the system a division by this surface will be introduced in the system of equations -> division by zero.For this reason a limitiation for the surface has been intoduced: as a minimum the surface area of one human and as a maximum a value of 1e+23 m2 (only needed for a complete parametrization of the model).
References
VDI 2078: Calculation of cooling load and room temperatures of rooms and buildings (VDI Cooling Load Code of Practice) - March 2012
Example Results
AixLib.Building.Components.Examples.Sources.InternalGains.Humans
AixLib.Building.Components.Examples.Sources.InternalGains.OneOffice
-
March 01, 2019 by Niklas Huelsenbeck:
Duplicated HumanSensibleHeat_VDI2078 Class and adapted it to a heat flux input value instead of a total number of persons -
March 23, 2015 by Ana Constantin:
Set minimal surface to surface of one person -
Mai 19, 2014 by Ana Constantin:
Uses components from MSL and respects the naming conventions -
April 10, 2014 by Ana Constantin:
Added a lower positive limit to the surface area, so it won't lead to a division by zero -
May 07, 2013 by Ole Odendahl:
Formatted documentation appropriately -
August 10, 2011 by Ana Constantin:
implemented
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Units.SI.HeatFlux | InternalGainsPeopleSpecific | 1.0 | Specific Heat Flow from people to the environment |
| Real | RatioConvectiveHeat | 0.5 | Ratio of convective heat from overall heat output |
| Modelica.Units.SI.Area | RoomArea | 20 | Area of room |
| Modelica.Units.SI.Temperature | T0 | Modelica.Units.Conversions.from_degC(22) | Initial temperature |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Modelica.Thermal.HeatTransfer.Interfaces.HeatPort_a | ConvHeat | ||
| AixLib.Utilities.Interfaces.RadPort | RadHeat | ||
| Modelica.Blocks.Interfaces.RealInput | Schedule |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| AixLib.Utilities.HeatTransfer.HeatToRad | RadiationConvertor | ||
| Modelica.Blocks.Math.Gain | internalGainsPeopleSpecific | ||
| Modelica.Blocks.Math.Gain | SurfaceArea_People | ||
| Modelica.Blocks.Nonlinear.Limiter | limiter | ||
| Modelica.Blocks.Math.Gain | gain | ||
| Modelica.Blocks.Math.Gain | gain1 | ||
| Modelica.Blocks.Sources.Constant | Area | ||
| Modelica.Blocks.Math.MultiProduct | productHeatOutput | ||
| Modelica.Blocks.Math.Gain | PersonHeat | Divides total heat by the Heat Output per Person to get number of persons |