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Modeling exhaust fans, VFD and air to air heat exchanger

Hi all,

I am fairly new to Energy Plus and I have a few questions regarding ventilation. I have been reading the Input/Output documentation and it is not clear to me if there is a fundamental difference between the “ZoneVentilation:DesignFlowRate” and the “Fan:ZoneExhaust” objects when used to model an exhaust fan. It seems to me that “ZoneVentilation:DesignFlowRate” has the ability to calculate an “adjusted” ventilation rate based on the B and C coefficient. “Fan:ZoneExhaust” seem to not be able to do that and also required to be part of an airloop (requires air nodes). Am I correct? Is there any other fundamental difference between those two objects?

My second question is about the ability to model an exhaust fan with VFD. It looks like none of the two previous objects can do that. The “Fan:ComponentModel” object seems to be able to take into account VFD. However, I am not sure if it can be used as an exhaust fan. Is it possible? If yes, what should I look into in order to model it properly?

My last question is about air to air heat exchangers. I’d like to be able to model a zone where a fan would provide some outdoor air and another would exhaust the same flow rate. I would also like to model an air to air heat exchanger (“HeatExchanger:AirToAir:FlatPlate” object) “in-between” them. It looks like I need to create an airloop which would contain both fans and the air heat exchanger. I’ve been looking into the “AirNetwork” objects but it seems to be used to model multi-zone airloop … What should I look into to create this simple loop?

Thanks a lot for your answers! I really appreciate your help.

Modeling exhaust fans, VFD and air to air heat exchanger

Hi all,

I am fairly new to Energy Plus and I have a few questions regarding ventilation. I have been reading the Input/Output documentation and it is not clear to me if there is a fundamental difference between the “ZoneVentilation:DesignFlowRate” and the “Fan:ZoneExhaust” objects when used to model an exhaust fan. It seems to me that “ZoneVentilation:DesignFlowRate” has the ability to calculate an “adjusted” ventilation rate based on the B and C coefficient. “Fan:ZoneExhaust” seem to not be able to do that and also required to be part of an airloop (requires air nodes). Am I correct? Is there any other fundamental difference between those two objects?

My second question is about the ability to model an exhaust fan with VFD. It looks like none of the two previous objects can do that. The “Fan:ComponentModel” object seems to be able to take into account VFD. However, I am not sure if it can be used as an exhaust fan. Is it possible? If yes, what should I look into in order to model it properly?

My last question is about air to air heat exchangers. I’d like to be able to model a zone where a fan would provide some outdoor air and another would exhaust the same flow rate. I would also like to model an air to air heat exchanger (“HeatExchanger:AirToAir:FlatPlate” object) “in-between” them. It looks like I need to create an airloop which would contain both fans and the air heat exchanger. I’ve been looking into the “AirNetwork” objects but it seems to be used to model multi-zone airloop … What should I look into to create this simple loop?

Thanks a lot for your answers! I really appreciate your help.

Modeling exhaust fans, VFD and air to air heat exchanger

I am fairly new to Energy Plus and I have a few questions regarding ventilation. I have been reading the Input/Output documentation and it is not clear to me if there is a fundamental difference between the “ZoneVentilation:DesignFlowRate” and the “Fan:ZoneExhaust” objects when used to model an exhaust fan. It seems to me that “ZoneVentilation:DesignFlowRate” has the ability to calculate an “adjusted” ventilation rate based on the B and C coefficient. “Fan:ZoneExhaust” seem to not be able to do that and also required to be part of an airloop (requires air nodes). Am I correct? Is there any other fundamental difference between those two objects?

My second question is about the ability to model an exhaust fan with VFD. It looks like none of the two previous objects can do that. The “Fan:ComponentModel” object seems to be able to take into account VFD. However, I am not sure if it can be used as an exhaust fan. Is it possible? If yes, what should I look into in order to model it properly?

My last question is about air to air heat exchangers. I’d like to be able to model a zone where a fan would provide some outdoor air and another would exhaust the same flow rate. I would also like to model an air to air heat exchanger (“HeatExchanger:AirToAir:FlatPlate” object) “in-between” them. It looks like I need to create an airloop which would contain both fans and the air heat exchanger. I’ve been looking into the “AirNetwork” objects but it seems to be used to model multi-zone airloop … What should I look into to create this simple loop?