Search Results

In modern vehicle air conditioning concepts, the temperatures at the outlets of the Heating Ventilation and Air Conditioning (HVAC) unit are controlled using temperature sensors in combination with an Automatic Climate Control (ACC) system. A novel coupled Proper Orthogonal Decomposition (POD) and Flow Resistance Network (FRN) model approach is proposed to accurately predict the temperatures at the outlets of a HVAC unit for real-time model based control. The integral enthalpy flow rates at the outlets, which result from a complex mixing process in the mixing chamber of the HVAC unit, are approximated by a linear combination of orthonormal POD modes. A FRN is established to compute the volume flow rates at the outlets. By combining the classical FRN with the POD model the weighting coefficients for the POD modes can be determined from the volume flow rates estimated by the network model.