# Advances in Diesel-LNG Internal Combustion Engines
## 2 Results
### Computational Proof of Concept of Novel Diesel-LNG ICE Designs  
ICE performance simulations are performed by using state of the art computer codes of the operation of turbocharged and super-turbocharged diesel and diesel-LNG ICEs. Description of the modeling strategy and past application to dual-fuel diesel-alternative fuel engines are presented in [59; 60; 61; 62; 63; 64; 65]. Simulations have been performed for an engine fueled in one case with diesel only, and one case with diesel and LNG. Pollutant emissions are disregarded. Figure 5 presents a sketch of a V6 TDI CAE model, that allows simulation of the operation of turbocharged, electrically aided turbocharged and super-turbocharged ICEs, for CI operation. Figure 5: Sketch of a V6 TDI model, with compressor and turbine shafts connected to the crankshaft. This model may be used to simulate super-turbocharging, with gears and a continuously variable transmission (CVT) toroidal mechanism connecting crankshaft and turbocharger shaft, as well as a motor-generator unit connected to the turbocharger shaft of electrically assisted turbocharging. In this case, post-processing is needed to deprurate the crankshaft power output of the power from/to the turbocharger shaft. Through the motor/generator unit (MGU-H), this extra power is delivered or extracted from the traction battery, also used by the kinetic motor generator unit (MGU-K) delivering power to the wheels or recovering the braking energy. Figure 6 is the sketch of the classic turbocharged solution. Computer-Aided Engineering (CAE) ICE performance simulations are very well known and very well established tools, with many different suppliers as well as users of products providing very close results in between them and with experiments. Modelling of V6 TDI engines is discussed in [65; 66; 67]. The ICE considered is a 3.7-L TDI V6, of bore 92.5 mm, stroke 90 mm, connecting rod length 180 mm, compression ratio 17.5. The V6 had a V-angle of 120 degrees. This ICE model was developed as part of a study for the ICE of a Federation Internationale de l'Automobile (FIA) world endurance championship Le Mans Prototype class1 hybrid car. Target performances were those expected from the Audi LMP1-H.  
With electrically assisted turbocharging, the total power at the crankshaft must be deprurated during post-processing of the difference between the power from the turbine and the power to the compressor. The extra power needed at the turbocharger is obtained from the battery, as the extra power produced by the turbocharged is delivered to the battery, through the electric motor/generator unit. In mechanically assisted turbochargers, the positive difference between the power from the turbine and the power to the compressor is multiplied by the mechanical transmission efficiency. The negative difference between the power from the turbine and the power to the compressor is divided by the mechanical transmission efficiency. In the case of a traditional, balanced turbocharger,  
Figure 6: Sketch of a V6 TDI model, with a traditional turbocharger. compressor and turbines are linked to each other through a shaft and disconnected from the crankshaft. While the efficiency of the mechanical connection to the crankshaft is relevant [40], it must be pointed out as this efficiency only weighs on the difference between the turbine and compressor works. Combustion is modeled through diesel Wiebe functions. Combustion is not predictive but correlative. It is modeled by using the same DI diesel Wiebe functions for the super turbocharged and turbocharged versions, diesel only and diesel-LNG.