Dry cooler 1.1
- Dennis De Beuckeleer
The dry cooler 1.1 BC is visualised in the figure below and is used as a production unit for cooling. For instance to supply cooling to the building, which is called “Free cooling”. It is also used to regenerate the soil when using geothermal energy storage.
Design
To calculate the UA-value or thermal conductivity of the dry cooler, the user has to insert the following parameters.
The secondary thermal power and regime temperatures are propagated from the end units to the dry cooler BC. This means the only thing needed to calculate the UA value is the external design temperature and the air volume flow rate.
The parameters of the heat exchanger are the following.
The KV-value is necessary to calculate the pressure drop over the heat exchanger at a certain flow rate, which is needed for the pump calculation.
The air volume flow and the UA-value are calculated in the software by doing the action “compute design flows”. It is calculated using the temperatures and thermal power previously mentioned. Both the air volume flow as the UA-value can be changed and locked by the user, in which the design conditions change at the air side of the heat exchanger. You cannot lock both the air volume flow as the UA value.
Simulation
In a simulation, controls are needed to make sure the dry cooler BC does what the user wants it to do. To control the BC correctly, a control signal is needed and should be attached to the square node on the edge of the BC.
If a signal between 0 and 1 is sent to this node, the fans will modulate between 100% flow rate, which is the design flow rate, and 0%.
After a simulation when the user hovers over the BC, the fan electricity consumption is visualised.