Model calibration, operative temperature measurement

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Hi Raghu,

thank you for your answer, really appreciating it. The internal gains are constant over time, so the only variation is in the HVAC power. Solar gains are in both time periods high (august, november), which explains the operative temperature curve. I am just trying to figure out, what could cause the sensor measurement being different. Shading from trees? Air velocity?

Yes, the purpose is, I am trying to match the simulated temperature to the measured temperature. Thus in some times the operative temperature is matching more than the mean

Thank you for your second answer, unfortunately I don't have acess to the sensors nor to the facility owners. I will read more to choose the right variable for calibration in the I/O reference

Hi Raghu, one more question: Does it make sense for you that the simulated Mean Air Temperature is constant (only varying in the second decimal), as in the Setpoint Temperature determined? My model is a 1Zone, Small container, constant Internal IT Equipment, cooling Only (enough cooling capacity to meet the cooling Loads.), Infiltration Rate at 0.5ACH.. Thank you, Sören

Hi @Soeren , The simulated mean air temp would be met by the simulated systems irrespective of the loads in the simulation if there is enough cooling capacity resulting in a constant temp. value. However, this may not be the case in real life due to various disturbances. If the aim of your study is to make sure your model matches the sensor data, then these disturbances would need to be introduced into the model. Schedules of occupancy, thermostats, other internal loads and mech equip sched. are the most important to be verified.