Abstract: Alternating torque {tilde over (M)}kv(?) or the mean indicated pressure Pml is to be determined from the angular velocity ? from the engine speed, for engine management, for example. Charge pressure compensation (5) must be effected in order for a usable result to be obtained. By preference sensor wheel error compensation (2) and inertial force compensation (4) are also effected. The mean indicated pressure Pml is obtained from the alternating torque {tilde over (M)}v(?) in a characteristic diagram.

Abstract: It is claimed that statements regarding cylinder pressure are obtained for optimization of the combustion process in internal combustion engines. The internal combustion engine is modeled with a plurality of model parameters (1 to 5) for this purpose. Once it has been acquired, a model alternating torque (MW) is compared to an actual alternating torque (IW). The model parameters are modified in accordance with the result of the comparison. The model yields realistic values of the combustion chamber value on the basis of the modified model parameters.