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How to set opening factors correctly?

asked 2018-11-07 08:50:39 -0600

Haohan Sha gravatar image

For modelling cooling effects of natural ventilation in an atrium, I use the airflow network in energyplus to simulate the natural ventilation. To control the conditions and calculate the change of cooling loads, I use the HVAC template Zone: Ideal Load Air system, and fix indoor temperature in 21 degree.

To control the natural ventilation, I use temperature as Ventilation control mode, and in the Ventilation Control Zone temperature setpoint schedule, I use 20.999 degree. Then, in the indoor and outdoor temperature difference lower limit for maximum venting open factor and upper limit, I set 9 and 9.001 to ensure the openings to be opened in 12-21 degree and opening factors in only 0 and 1.

However, I found the opening factors still have some values less than 1.0, like 0.5, why?

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answered 2018-12-10 18:57:04 -0600

Haohan Sha gravatar image

This is because I set the Output:variable in the hourly, and energyplus will automatically calculate the average of opening time. I change it to the "detail", it can be found that the open factor only have 1 and 0.

Furthermore, to set open factors based on a complex conditions, for example, relating to the both of outdoor temperature and humidity, I recommend using the EMS in the energyplus.

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Asked: 2018-11-07 08:50:39 -0600

Seen: 183 times

Last updated: Dec 10 '18