Key outcomes

  • Optimal fan, fuel cooler and louvre configuration achieved
  • Performance requirements met

Charge air coolers (also known as intercoolers or aftercoolers) are used in modern turbocharged petrol and diesel engines to reduce the temperature of charge air that is passing from the turbocharger to the engine. Cooling the charge air increases charge density and reduces combustion temperatures, which helps to improve engine performance and reduce emissions. In this study, Synergetics Consulting Engineers employed computational fluid dynamics (CFD) to model and optimise the performance of a diesel locomotive charge air cooler unit.

Charge air cooler heat exchanger

Figure 1: An electric motor and fan inside the charge air cooler unit. The inlet to the charge air pipe is visible at the lower right-hand corner of the unit.

The charge air cooler acts as a heat exchanger by using two large fans to drive cool ambient air flow around a warmer charge air pipe. The complete system was modelled numerically and the model was validated against experimental measurements provided by the manufacturer. Synergetics then tested a range of different fan, fuel cooler and louvre configurations to determine which configuration would provide optimal cooling performance. The results allowed the manufacturer to demonstrate that the air cooler unit would meet performance requirements under a range of different operating conditions.

Charge air cooler intercooler CFD

Figure 2: Streamlines and temperature contours inside the charge air cooler unit.