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With the rise of electric autonomous vehicles, it has become clear that the cabin of tomorrow will drastically evolve to both improve ride experience and reduce energy consumption. In addition, autonomy will change the transportation paradigm, leading to a reinvention of the cabin seating layout which will offer the opportunity to climate systems team to design quiet and even more energy efficient systems. Consequently, Heat and Ventilation Air Conditioning (HVAC) systems designers have to deliver products which perform acoustically better than before, but often with less development time. To success under such constraints, designers need access to methods providing both assessment of the system (or subsystems) acoustic performance, and identification of where the designs need to be improved to reduce noise levels. Such methods are often needed before a physical prototype is requested, and thus can only be achieved in a timely manner through digital testing.

Radiator thermal cycle test is a test method to check out the robustness of a radiator. During the test, the radiator is going through transient cycles that include high and low temperature spikes. These spikes could lead to component failure and transient temperature map is the key to predict high thermal strain and failure locations. In this investigation, an accurate and efficient way of building a numerical model to simulate the transient thermal performance of the radiator is introduced. A good correlation with physical test result is observed on temperature values at various locations.

In this article, the behavior of a typical air-to-air heat exchanger (intercooler) during the thermal shock test has been recorded during which the heat exchanger is exposed to very high temperature gradients. Different CAE models have been built that have different levels of details and the sensitivity of the results to the details has been studied. Finally a comparison have been made between the results of the CAE/CFD model and the experimental data and the correlation study shows that in spite of being simple, the dual stream is very accurate and correlates pretty well with test data. Including all design details in the CAE model will not necessarily improve the accuracy of the model while adding up to the computational cost.

Requirement for more compact and more efficient fan systems to improve the automotive thermal management has urged Valeo to develop a complete automatic CFD procedure to numerically simulate the fan system. The present study has focused on the description and the validation of the flexible grid template that is meant to simulate the internal flow field within the fan system. This template closely fits in the previously developed rotor-stator parametric grid. The initial small rib reference design has been meshed and four different large rib cases with increasing geometrical difficulties have helped testing this new capability. The simulations have been performed on a medium size grid that has been shown to capture most of the important flow features. The ribs act as centrifugal pumps that drain airflow through the electrical motor. Larger ribs are shown to increase the flow rate through the motor by up to 25% with a marginal increase with swept ribs compared to radial ones.

Requirement for more compact and more efficient fan systems to improve the automotive thermal management has urged Valeo to develop a complete automatic CFD procedure to numerically simulate the fan system. The present study has focused on the description and the validation of the flexible grid template used for the rotor-stator configurations. Three different efficient stators with increasing geometrical difficulties have helped testing this new capability. Grid refinement has been assessed and comparisons have been made between the initial stand-alone rotor and the same rotor with the three different stator designs. The simulations have been performed on a reasonable grid size that has been shown to capture most of the important flow features. The efficiency improvement brought by these stators has been clearly highlighted and estimated to be about 10%.

In order to improve the reliability of fan design and the prediction of underhood engine cooling based on CFD, Valeo Motors and Actuators and Michigan State University have teamed up to develop a comprehensive experimental and numerical database. The initial focus has been on the simulations of the isolated fan environment in two different test facilities. To understand the discrepancies observed in the comparisons of integral performances, the first detailed hot wire measurements on the MSU test facility have been collected. The data are split into mean velocity components and RMS fluctuations. The former are successfully compared to three detailed turbulent numerical simulations of the corresponding facilities.

Thermal study of electric engine cooling (EEC) motors is conducted using 3D CFD and conjugate heat transfer analysis. Complicated airflow fields and temperature distribution inside the motor are obtained. Predicted temperatures agree well with experimental results.