Ventilation system, a method of operating a ventilation system, a duct section to be used in a ventilation system, and the use of such duct section

A ventilation system, the ventilation system comprising a main duct connected to at least one motorized fan rotatable at a selectable rotation speed, and further connected to at least one workplace via a local duct arrangement, a gate arranged in a position between the workplace and the main duct and a control computer,

• wherein said local duct arrangement comprises an asymmetrical bend duct section having a straight duct portion connected to a bend duct portion that together define an inner curvature of the asymmetrical bend duct section, said asymmetrical bend duct section being defined by a circumferential wall portion delimiting an interior of the asymmetrical bend duct section and forming a first duct opening facing the workplace and a second duct opening facing the main duct,
• said ventilation system further comprising a first pressure sensor arranged exteriorly of the asymmetrical bend duct section and in fluid communication with the interior of the asymmetrical bend duct section via a first through-going opening arranged at a first position in the circumferential wall portion of the straight duct portion, and
• a second pressure sensor arranged exteriorly of the asymmetrical bend duct section and in fluid communication with the interior of the asymmetrical bend duct section via a second through-going opening arranged at a second position in the circumferential wall portion of the bend duct portion or in a duct section connected to the bend duct portion, wherein said first and second positions are arranged along the inner curvature of the asymmetrical bend duct section,
• wherein said first and second pressure sensors are configured to communicate with the control computer,
• wherein said control computer is configured to determine, based on input signals from the first and second pressure sensors, a pressure difference between the first and second positions of the through-going openings of the first and second pressure sensors, said pressure difference attributable at least in part to turbulence induced by said asymmetrical bend duct section, and
• wherein said control computer is further configured to control the rotation speed of the motorized fan based on the determined pressure difference.