March 6 - 8, 2017 | Berlin
LEADING ENGINEERING SIMULATION CONFERENCE
The influence of thermal underhood environment on the engine intake air for a race track application
The continuous reduction of the CO2-emissions in combustion engines, mostly achieved by displacement downsizing in combination with air charging system, has helped turbocharged engine to gain increasingly great importance. However, rising boost pressure demands calls for enhanced cooling of the charged air. Charge-air-cooling must manage not only the compression heat, but also the heat absorbed by the air induction system on the low pressure side due to heat convected and radiated in the engine compartment. Therefore, the choice of the appropriate charge-air-cooler is not solely determined by the degree of compression.
The determination of the transient thermal conditions of the intake air presupposes a thermal consideration of the engine and engine compartment. To determine the thermal influence of the hot components on the loading air conduction, a transient thermal simulation of the under hood must be carried out with regard to the engine air intake ducts. This simulation must also consider the transient external conditions (e.g. speed, wind direction, acceleration, etc.).
The transient thermal underhood simulation with STAR-CCM+®, one of the core competences of InDesA, is coupled with 1D GT POWER simulation of the engine under the influence of the thermo-dynamic state of the charged air on the operating condition of the engine and its changing demands (aerial need) as well as its back coupling in the thermal system vehicle (heat load, exhaust). This will be demonstrated for a race track application.
From the exact knowledge of the thermo-dynamic state of the charged air important information for the dimensioning of charge air coolers can be gained. Beyond, the information about the air temperature in dependence of the operating condition of the engine allows for optimization steps of the charge air coolers to increase the overall efficiency of internal combustion engines.