Abstract: A filter element has a first follower element with a first traction surface and a second follower element with a second traction surface provided for interacting with first and second mating surfaces of the filter housing, respectively. The first and second traction surfaces interact with the first and second mating surfaces to pull out the filter element from the filter housing. The first and second traction surfaces are spaced apart from each other along a longitudinal axis of the filter element and project radially into the interior of the filter element. At least one of the first and second follower elements has a stop surface adjoining circumferentially the respective traction surface. In a position of use, the stop surface interacts with a counter stop surface of the filter housing to form an at least unidirectional rotational degree of freedom blocking about the longitudinal axis relative to the filter housing.

Abstract: A method for burning liquid fuels, wherein an amount of total combustion air required for burning is introduced into the liquid fuel in the form of small air bubbles to provide a highly variable overall heat output, particularly at least within a range of one to fifty times the amount of heat output in a similar system, where the liquid fuel/air mixture produced is at least 10 bar. The combustion air is intermittently fed to an injection nozzle protruding into a combustion chamber and is atomized there to produce an explosion at a constant injection pressure. The duration of each of the liquid fuel/air mixtures introduced with each fuel injection pulse is kept constant at a desired value and the total amount of the liquid fuel/air mixture injected per time unit is adjusted between constant fuel injection pulses by varying the duration. The remaining amount of the combustion air is introduced in the combustion chamber through an air nozzle annularly surrounding the port of the injection nozzle.

Abstract: A method for burning liquid fuels, wherein an amount of total combustion air required for burning is introduced into the liquid fuel in the form of small air bubbles to provide a highly variable overall heat output, particularly at least within a range of one to fifty times the amount of heat output in a similar system, where the liquid fuel/air mixture produced is at least 10 bar. The combustion air is intermittently fed to an injection nozzle protruding into a combustion chamber and is atomized there to produce an explosion at a constant injection pressure. The duration of each of the liquid fuel/air mixtures introduced with each fuel injection pulse is kept constant at a desired value and the total amount of the liquid fuel/air mixture injected per time unit is adjusted between constant fuel injection pulses by varying the duration. The remaining amount of the combustion air is introduced in the combustion chamber through an air nozzle annularly surrounding the port of the injection nozzle.