Keyword *ACCU

The keyword *ACCU is used to define an accumulator in a node.

FORMAT:

*ACCU  <NodeID, Tmax, Tmin, Volacc, Hloss, Tini, Ts, Pnom>

Where:

NodeID:                  Node identification

Tmax:           The maximum temperature in the accumulator. (°C).

Tmin:            The minimum temperature in the accumulator. (°C).

Volacc:                   The accumulator's active volume. (m3).

Hloss:           A heat loss coefficient which, when multiplied by

                   the average temperature in the accumulator and the average ambient

                   temperature, gives the loss in kW.  (kW/°C).

Tini:              Initial average temperature in the accumulator. (°C).

Ts:               The average ambient temperature. (°C).

Pnom:           Nominal power. If simulation is used for

dimensioning of accumulators, Pnom must not be entered, i.e. 9.9999E+30 or “*” must be entered. (kW). If Pnom is positive energy is stored in the accumulator. If Pnom is positive energy is delivered from the accumulator. Note that if *COOL is active you have to think the other way around.

 

Note that the keyword *ACCU must be entered after the keyword *NODE.

Note that if the node is provided with an accumulator, no other devices are permitted in the node (e.g. a bypass).