Adaptive real time combustion-kinetic-control modelling approach for FPE applications
Start date1 October 2019
Fully funded. UK/EU students only.
Funding sourceDoctoral College Studentship Award, matched by Libertine Ltd
Free piston engines (FPE) are considered a promising power source for hybrid electric vehicles. In comparison with conventional crankshaft engines, an FPE has the potential to achieve higher efficiency, smoother operation and fuel flexibility.
This project will be carried out in collaboration with the industrial partner Libertine FPE who will provide the model framework including the preliminary combustion and kinetic engine models. In order to optimise the holistic engine control strategy and algorithm over a wide operation conditions, real-time combustion models will be developed to simulate different combustion modes, and the entire engine platform will also be developed which can adapt different sub-models in different operation conditions. This is a novel approach and vitally important when developing the engine geometries and control strategies.
The objectives include:
- Conduct literature survey to understand the state-of-the-art of FPE research and development
- Develop and implement real time combustion models for SI and HCCI combustion
- Integrate the combustion models to the 1D engine kinetic model
- Develop the adaptive FPE modelling platform
- Validate the model with testing results
- Optimise the control strategy to achieve better steady-state and transient engine performance
- Prepare academic publications and dissertation.
FPEs are a novel type of internal combustion engine primarily for hybrid electric vehicle (HEV) power generation. In comparison with conventional crankshaft engines, they have advantages including higher efficiency due to high compression ratio and lower friction losses, more compact and lightweight design due to integrated engine and generator, lower vibration and noise due to symmetric design and operation, and fuel flexibility due to variable compression ratio.
The successful development of FPEs will promote the market penetration of HEVs thus contributing to the reduction of CO2 and other harmful emissions. Commercially, this technology will allow a modular and flexible vehicle powertrain configuration, which combines the advantages of both IC engine and electric powertrains system and avoids their problems, therefore having a good potential to be successful.
As a typical powertrain for an HEV, the FPE is designed to operate in a limited number of steady conditions in order to simplify the design and improve fuel economy. The operation points are stop, quiet point, efficient point and power point, which corresponds to the operation condition of pure electric driven (thus engine stops), low engine output to charge the battery (thus engine will operate quietly), mid-load engine output to charge the battery (at its best efficiency point), and highest power output point, respectively, as well as the transient process in between the steady points.
Due to the flexible compression ratio, different combustion technologies can be implemented to achieve the best efficiency and lowest emissions. These involve conventional spark ignition premixed turbulent combustion for quiet and power points, and Homogeneous Charge Compression Ignition (HCCI) combustion which gives the best efficiency and lowest emissions at efficient point. In order to develop the control strategies and algorithms that allow the engine to operate reliably and efficiently, as well as a smooth transfer between the different modes, an adaptive model (which is called the combustion-kinetic-control, CKC model) is essential.
This model should be in real time in order to implement control algorithms, however the sub-models, particularly the combustion models for various modes, must be adequately accurate to represent different combustion scenarios. This model, once developed, will be able to act as a generic FPE development platform and toolkit to implement various sub-models and quantitatively assess control quality for engine design and control optimisation, therefore this project is of significant academic and engineering values.
Related linksCentre for Automotive Engineering
Open to UK / EU students with BEng / MEng or MSc in Mechanical, Automotive, Aerospace Engineering or equivalent.
IELTS requirements: minimum 6.5 with at least 6.0 in each individual category.