Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.
The present investigation deals with the challenges in all
vehicle industries with respect to air conditioning taking into
account transient effects. Transient phenomena occur mainly
during door opening and closing, pre-cooling, pre-heating.
Numerous vehicles have difficulties to meet the thermal
comfort criteria which are imposed by the customer. Typically,
requirements are given for the minimum and maximum air
velocity, the temperature level, the maximum gradient in
different sections and the fresh air rate. More sophisticated
requirements includes the predicted mean vote (PMV) and
predicted percentage dissatisfied (PPD). Tools which are
capable to predict the impact of relevant design options have
been used in steady state for several years already. The
possibility to use these tools for transient processes in an
industrial framework will be discussed.