Heat Flows

While all units can be connected to other units with ordinary streams, some units can additionally be connected with heat flows. These are indicated by red and blue handles on the units

Red handles indicate heat sources, while blue handles indicate heat sinks. We create heat flows the same way as we connect streams, by clicking and dragging from a source handle to a sink handle.

In this example, we are transferring the heat produced in the reactor to a heater, which dumps the heat into a water stream. Once we've connected the units, we can select the heater, and choose "Heat from Source", to indicate that the heater should use the heat delivered from the heat stream.

Selecting the reactor, we can choose to specify either the temperature change in the reactor, or the amount of heat we would like to supply (or remove).

Note: You can not select the "Heat from Source" or "Heat to Sink" option on both units connected via a heat stream. This is because one of the units must have a specification that makes the heat stream well defined.

In this example, we've selected that the reactor outlet temperature should be 50 K higher than the inlet temperature. After running the calculation, we can view the properties of the heat flow.

Here, we can see that the source (the reactor) is delivering 8341 kW of heat at a temperature of 350 K. However the sink (the heater) only has the capacity to absorb 936.8 kW, and so only 936.8 kW is transferred through the connection. The excess heat delivered by the source, which the sink is incapable of absorbing, is dumped to the surroundings.

In the same way as shown here for a reactor/heater pair, a cooler can be used as a heat source for another unit. In that case, the heat extracted by the cooler can be transferred through a heat flow connection in order to power a heater, or deliver heat to a reactor that is absorbing heat.

Finally, instead of specifying that the heater should use all heat delivered from the source, we can specify the outlet temperature of the heater, and select the "Heat to Sink" option on the reactor. In this case, it is the heater that specifies how much heat it is capable of absorbing, and the reactor will attempt to deliver enough heat to saturate it. As in the example shown here, a warning will be issued if the source and sink capacities are incompatible, such that heat must be either taken from or dumped to the surroundings.