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Details on Infiltration and Material Throughput

Information on the Infiltration and material throughput dialog in dynamic cooling load calculation.

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Module overviewCooling load dynamicRoom levelCooling load dynamicInfiltration

Table

For infiltration and material throughput, you can assign room-specific load profiles.

Important:

If the air that enters the room via infiltration has already been cooled by the system, the cooling effort is not calculated into the cooling load here. Only the cooling effect on the room air is considered at this point.

Column

Description

Qty.

Number of air diffusers or sources of material throughput. The load is multiplied by the quantity.

Usage profile sets

Displays the currently assigned usage profile set. Click to open the Usage Profiles dialog, where you can select additional profile sets or create new ones.

Name

Click to open a dialog with a list of templates for calculating the load, depending on the load type When a template is selected, the data from the template is copied to the table. After the data transfer, the name can be adjusted manually (existing templates remain unaffected by the manual adjustment).

Volume flow rate m3/h

The air volume flow entering the room via a air handling unit or via leaks from the adjacent room or from outside. If you have specified the specific air volume flow, this value is determined automatically.

Volume flow rate m3/hm2

Specific air volume flow: this value is determined automatically if you have specified the absolute volume flow rate.

Air change 1/h

Number of air changes per hour. This value can be specified as an alternative to the volume flow rate. The respective other value is automatically calculated.

Density in kg/m3.

The density of the air is automatically suggested for infiltration. For locations at a very high altitude above sea level it may be useful to adjust the value.

T(entry) °C

Temperature of the air or material as it enters the room.

Rel. humidity %

For infiltration, the humidity of the incoming air is set here with either external or Room humidity, depending on the input in T(entry) °C.

T(exit) °C

Temperature of the material when it leaves the room.

Usage %

Percentage to which the selected profile set is used. This value is considered in addition to the usage values in the profile set. Accordingly, a profile of 50% with a usage of 50% is 25% effective.

Type of infiltration

You can choose from different types of infiltration:

  • Infiltration (passive): Input value is converted into power and flows into the calculation as internal load.

  • Supply air cooling, controlled (counted): the determined performance of the air volume flow is used in results like a part of a cooling system. The cooling capacity is modulated so that it is reduced if the cooling load is too high and the design temperature remains constant.

  • Supply air cooling, uncontrolled (counted): The capacity is not regulated and is fully taken into account. If the cooling capacity is greater than required, the room temperature will drop below the design temperature.

  • Window ventilation, constant: Simplified simulation of ventilation by opening windows. The input value is converted into a capacity and flows into the calculation as an internal load.

  • Window ventilation, constant (manually): The volume flow is constant because the window is either open or closed. The volume flow becomes active (= window open) when the room air temperature is at least 1 K above the target temperature and the outside air is at least 1 K below the room temperature. These values can be adjusted in the configuration.

  • Window ventilation, variable (controlled): Like manual window ventilation, but because of machine control the volume flow can also accept intermediate values to approximate the target temperature.

Mass flow rate kg/h

Mass flow rate of the material throughput in kilogram per hour.

Capacity Wh/(kgK)

The heat capacity of the respective material at mean temperature.

Convection %

The portion of the load that has a convective effect and is directly emitted into the room air. The effect of the radiation component in the room is delayed.

Vapor em. g/h

Vapor emission by internal loads in grams per hour. This value is used for the calculation of the humidity balance.