Principles of 0D/1D Engine Tuning (automatic translation by Shopify)
In the first phase of redesigning an internal combustion engine , it is not necessary to know all the thermal and flow phenomena and chemical reactions taking place in the engine. At this stage of engine tuning , it is important to optimize the entire system with the necessary accuracy. That is why the processes taking place inside each component are modeled with a certain approximation.
The components of our model can be divided into two categories:
- connecting elements,
The connecting elements within the model represent the gas exchange lines. This network of pipes connects the various "devices" that make up the rest of the model. These are e.g. valves, camshafts , cylinders, pistons , chambers, carburetors , pipe connections, etc. During the modeling of the latter components, the processes taking place in the given sub-unit are calculated using averaged values, no information is available on the spatial movement of the gas particles. In some cases, only the numerical value determining the volume of the given component is known, its external dimensions are unknown, so these components are 0D elements of the model.
On the other hand, when modeling the connecting elements (e.g. intake pipe, exhaust pipe ), it is necessary to know the gas flow. In order for the model to provide a sufficiently accurate result within a reasonable time even with the generally available computer background, only the gas movement in the direction of the flow is modeled. Therefore, the calculations describing the movement are missing the calculations determining the displacements perpendicular to the axis of the pipes. These components are the 1D elements of the model.
Of course, if necessary, the modeling software can be connected to parallel flow modeling programs ( CFD software ), which calculate the 3D flow characteristics of certain components (e.g. air filter box, catalyst, etc.). In other words, the input data of the CFD program calculations is provided by the 0D/1D engine model, while the output data provided by the CFD program of the selected component is fed back into the engine model. Thus, the accuracy of the models can be significantly improved, but the time spent on calculations and the software and hardware costs increase significantly.
With this method, we can already decide before the implementation of the tuning whether the planned changes will really increase performance , or the result will only be a waste of time and money.
Construction of 0D/1D engine model