Calender and method for controlling such a calender

A calender, comprising:

• a rotatable roller, which roller is hollow and thereby defines an internal space which is configured to be filled at least partially with a heatable fluid;
• a belt, co-acting with the roller, with a determined belt pressure, wherein at least one material for feeding through the calender is situated between the roller and the belt for a determined contact time during throughfeed through the calender;
• heating means for heating the fluid, which heating means are disposed in the internal space;
• and
• one or more control means for controlling the heating means and/or the belt pressure and/or the contact time,
• wherein the calender comprises flow influencing means for initiating and/or influencing a flow of the fluid in the internal space, wherein a further control means are configured to control the flow influencing means and thereby the flow of the fluid in the internal space in freely settable manner, such that a flow speed of the fluid can be set.