Dear all, I am still comparing energy balance of HB with Steady-state calculation for an office space. I used ventilation losses=ventilation rate * air density* heat capacity of air * (wet bulb temperature - indoor air temperature), infiltration losses=infiltration rate * air density * heat capacity of air * (wet bulb temperature -indoor air temperature) for steady-state calculation. Here, heat capacity of air = 1000 J/kg.K, and air density changes with dry bulb temperature.
I made a figure for the hourly comparison between HB and Steady-state. In winter and transition seasons, ventilation and infiltration losses are almost the same. However, in summer, there are some times (during working time) that the ventilation and infiltration losses are postive, even outdoor air temperature is lower than inside air temperature.
Does anyone have an idea about why ventilation and infiltration losses are positive in these periods when outdoor temperature is lower than indoor air temperature?