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Several race car competitions seek to limit engine power through a rule that requires all of the engine combustion air passes through a hole of prescribed diameter. As the approach and departure wall shapes to this hole, usually termed orifice or restrictor are not prescribed, there is opportunity for innovation in these shapes to obtain maximum flow and therefore power. This paper reports measurements made for a range of restrictor types including venturis with conical inlets and outlets of various angles and the application of slotted throats of the ‘Dall tube’ type. Although normal venturis have been optimized as subsonic flow measuring devices with minimum pressure losses, at the limit the flow in the throat is sonic and the down stream shocks associated with flow transition from sub-sonic to sonic are best handled with sudden angular changes and the boundary layer minimized by the corner slots between the convergent and divergent cones.

In recent times new tools have emerged to aid the optimization of engine design. The particle swarm optimizer, used here is one of these tools. However, applying it to the optimization of the S.I. engine for high efficiency and low NOx emission has shown the preference of ultra lean burn strategy combined with high compression ratios. For combined power, efficiency and emissions benefits, there are two restricting factors, limiting the applicability of this strategy, knocking and cyclic variability. In the ultra lean region, knocking is not an important issue but the variability is a major concern. This paper demonstrates the application of a variability model to limit the search domain for the optimization program. The results show that variability constrains the possible gains in fuel consumption and emission reduction, through optimizing cam phasing, mixture and spark timing. The fuel consumption gain is reduced by about 11% relative.

The specific power densities and therefore the level of sophistication and costs of FIM-MOTOGP engines 800 cm3 in capacity have reached levels similar to those of the traditionally much more expensive FIA-Formula One engines and some racing developments have no application at all in the development of production bikes. The aim of the paper is therefore to review FIM-MOTOGP engine rules and make recommendations that could reduce costs and make racing more directly relevant to the development of production bikes while enhancing the significant interest in technical innovation by the sports' fans.

A real time energy management (EMS) optimizing algorithm is introduced that performs similar to offline dynamic programming (DP) for parallel HEVs. The EMS and the DP are compared, especially with the addition of a local hill climbing technique, to the example performance prediction of the fuel consumption of a 1.67 tonne large car using a 50 kW Honda Insight engine (representing 65% power reduction from standard) as reference. Then the performance of the vehicle in HEV mode, with a parallel 30 kW motor/generator is examined. The average improvement of this vehicle over five drive cycles from around the world is about 50% reduction in fuel consumption. Next the engine is replaced with an advanced SI turbocharged engine with assisted ignition which returns the performance to that expected of this class of car i.e. 0-100 km/h acceleration time of 7 s. This results in a 14% average reduction in fuel consumption across the five cycles compared with the base Honda engine.

There are two parts to achieving the optimization reported here. The development of an engine simulation model and an optimization algorithm. The engine performance is evaluated using a quasi-dimensional engine combustion model with sub models to incorporate friction, heat losses and abnormal combustion, that is knocking. After extensive search and development a new Particle Swarm Optimizer (PSO), has been developed. Optimization includes, for the first time, the search of discontinuous design variables. The input variables considered for this investigation are manifold air pressure, air-fuel ratio, spark timing, compression ratio, valve timing events including valve open duration, maximum valve lift and engine speed. This enables the identification of the maximum thermal efficiency at a given power output at any engine operating speed.

The challenge of tough fuel consumption reduction targets and near zero NOx emission standards can be met by optimization of the full range of engine design variables. Here these are explored through an engine simulation model and the application of an optimizing algorithm that can work in discontinuous data space. The combustion model has main features that include flame propagation, the effects of turbulence, chamber shape interaction and NOx formation. Two engine configurations are used to illustrate the application of the model and optimizer. Both allow the adoption of extra lean burn possible with LPG as fuel and EGR through an external route or cam phasing. In the first the compression ratio and cam profiles are fixed, in the second study they are also optimized.

The Australian Concept Car was developed with support from a wide range of industry and government sectors. The estimated energy consumption over the vehicle life cycle is presented relative to a typical Australian Upper Medium Class car fleet. Several assumptions are made about the performance of the prototype car, when extrapolating it to a production counterpart for the comparison. Production methods are one area, covered by a survey of suppliers, and particularly in-service fuel use has had to be estimated using validated procedures. Uncertainties exist about the level of recycling at the end of the vehicles projected life after 225,000 km, leading to defined uncertainties. It is concluded that the concept car will have an energy reduction of 15-17.5% and the life cycle CO2 emissions will be reduced by a little less.

The 2023 FISITA White Paper (for which the author was a contributor) on managing in-service emissions and transportation options, to reduce CO2 (CO2-e or carbon footprint) from the existing vehicle fleet, proposed 6 levers which could be activated to complement the rapid transition to vehicles using only renewable energy sources. Another management opportunity reported here is optimizing the vehicle’s life in-service to minimize the life-cycle CO2 impact of a range of present and upcoming vehicles. This study of the US vehicle fleet has quite different travel and composition characteristics to European (EU27) vehicles. In addition, the embodied CO2 is based on ANL’s GREET data rather than EU27 SimaPro methodology. It is demonstrated that in-service, whole-of-life mileage has a significant influence on the optimum life cycle CO2 for BEVs and H2 fuelled FCEVs, as well as ICEs and PHEVs.