A pharmaceutical company which produces medicines in cleanrooms has asked Actiflow to provide insight into the conditions in a cleanroom when reducing the ventilation rate of sterile air.
The ultimate goal was to reduce the flow rate, and therefore the energy costs (cooling, heating and fan energy), whereas the conditions of the cleanroom had to remain within the given limit values.
Actiflow has modeled the cleanroom, adding the intern pollution sources. After this, two phases were considered: ‘in operation’ and ‘at rest’. A stationary calculation was performed for the phase ‘in operation’, whereby a continuous flow of pollution was being produced. A time dependent calculation was performed for the phase ‘at rest’, which determined the time required to ventilate a certain amount of pollution. Both phases were considered at the current ventilation rate, and at two lower rates. For validation, the results of the current situation were compared to measurements of the actual recovery time. The results showed a very good match. The calculations at lower flow rates showed us that the required quality level can be guaranteed when the flow rate is reduced to a certain level. This is how Actiflow helped to make the cleanrooms more sustainable.