Abstract:
A heating, ventilation, and air conditioning (HVAC) system for a vehicle includes an evaporator and a diffuser. The evaporator is configured to cool air passing through the evaporator. The diffuser is configured to direct a first portion of the air entering the diffuser through a first section of the evaporator, and direct a second portion of the air entering the diffuser through a second section of the evaporator. The evaporator and the diffuser are configured to cooperate such that air exits the first section at a first temperature and air exits the second section at a second temperature less than the first temperature.
Abstract:
An automotive HVAC system includes upper and lower mode cases configured to discharge separate streams of temperature-conditioned air into front and rear passenger zones. The system separates the inlet air into separate mixing chambers, and a third stream through a heater core. Blend doors control hot and cold air streams entering their respective mixing chambers. Operation is controlled by reading requested temperature, blower rate and mode for system zone outlet, converting requests to a flowrate, calculating total flowrate as a summation of all requests, employing a math model to calculate total zonal flowrate as a summation of all zonal flowrates, calculating a blower control error as a function of the difference between total blower request and total zonal flowrate, modifying the operating state using the calculated control error, positioning and resetting the mode valves into defrost, heater and vent openings, and resetting the mode valves.