Study discipline:Dopravní prostředky a infrastruktura: Dopravní prostředky
Abstract:
The AC condenser plays a vital role in HVAC systems (Heating Ventilating Air
Conditions). In vehicles, it is typically located within a cooling pack, alongside other
heat exchangers. The dissipation of heat from the AC condenser directly affects
surrounding components. Therefore, accurate modeling of heat transfer between
the refrigerant and air is crucial for vehicle development, especially nowadays for
battery electric vehicles.
The proposed model enhances the spatial distribution of heat transfer, resulting
in improved air temperature predictions. The proposed model is based on the
well-known and established ? - NT U approach and iterative takes into account
the appropriate relation according to the refrigerant phase during the condensation
process occurring in the condenser. Additionally, the approach reduces the amount
of required input data and relies on directly measured condenser characteristics,
leading to more generic approach.
In the thesis, a dedicated test equipment was developed for input data measurement and model verification. The proposed model was tested under two distinct
conditions and compared with measurements. The model exhibited good agreement
with the measurements in predicting refrigerant inlet and outlet temperatures, as
well as relatively good agreement in air outlet temperature prediction. Furthermore,
additional development tasks were identified as well.