Hi, Andrew
I noticed that you are only using heating, I assume that you do have a cold Winter.
In Canada, all the residential house has a basement for water main to enter the house, so that it will not be frozen in Winter.
The gas furnace is mounted in the basement. The furnace is rectangular in shape and has two ducts. There will definitely a horizontal one to distribute the warm air, from the top of the furnace box. The return air may enter the box from the bottom where the fan is mounted. I have seen such a picture in the EPlus document.
In my condo, there are two ducts at the ceiling level, one for warm air and one for return air.
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For a bungalow, the return duct may not be present. The air flowing down the starcase to the basement and the fan filter is sufficient for the convection flow. The hot air is forced upwards near the wall and windows. Kitchen and bathrooms will have small exhaust fans.
You do have a return duct from the hall way. You may ignore this or model it as a zone with air mixing from the other zones, to keep the temperature the same as the other zones.
To make it plenum, simply declare this as a zone (plenum) and use it as a mixer of the air loop. You need not have to declare how the room air get into the plenum zone. All the air flow through the ATU's will enter this plenum as return air in simulation.
You may declare an additioanal infiltration for air leak to outside air, and add an OA intake with an OA mixer box..
The furnace will have a fresh air piple and a chinmey pipe. These are usually not simulated, although the chimney pipe is suitable to act as inlet air pre-heat.
======================
In a two or three storey house, part of the partition wall space is used as vertical is used a the return air duct with a grill opening at each upper floor. This is usually away from the stair case and thus have two return parths from the upper floors.
The air outlet cover usually has a adjustable slider. This is the EPlus ATU:..:uncontrolled.
=======================
If you need to study the temperature in the house, then divide the floor area into more zones as the 5Zone exmple model, or in actual room divisions. Rooms without a hot air outlet would be a passive zone. Heating can be assumed to be by wall conduction or with some zone air mixing from the other rooms.
How the air is returned from each zone to the furnace is not very emportant. With a constant volume fan, a fixed fraction of this volume enters a zone, and the same amount leave the zone at a different temperature. This heat balance or difference causes the zone temperature to be slightly above or below the controlled AHU supply air temperature.
==================
Full Airflow network is designed to work
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I noticed that you are only using heating, I assume that you do have a cold Winter.
In Canada, all the residential house has a basement for water main to enter the house, so that it will not be frozen in Winter.
The gas furnace is mounted in the basement. The furnace is rectangular in shape and has two ducts. There will definitely a horizontal one to distribute the warm air, from the top of the furnace box. The return air may enter the box from the bottom where the fan is mounted. I have seen such a picture in the EPlus document.
In my condo, there are two ducts at the ceiling level, one for warm air and one for return air.
==================
For a bungalow, the return duct may not be present. The air flowing down the starcase to the basement and the fan filter is sufficient for the convection flow. The hot air is forced upwards near the wall and windows. Kitchen and bathrooms will have small exhaust fans.
You do have a return duct from the hall way. You may ignore this or model it as a zone with air mixing from the other zones, to keep the temperature the same as the other zones.
To make it plenum, simply declare this as a zone (plenum) and use it as a mixer of the air loop. You need not have to declare how the room air get into the plenum zone. All the air flow through the ATU's will enter this plenum as return air in simulation.
You may declare an additioanal infiltration for air leak to outside air, and add an OA intake with an OA mixer box..
The furnace will have a fresh air piple and a chinmey pipe. These are usually not simulated, although the chimney pipe is suitable to act as inlet air pre-heat.
======================
In a two or three storey house, part of the partition wall space is used as vertical is used a the return air duct with a grill opening at each upper floor. This is usually away from the stair case and thus have two return parths from the upper floors.
The air outlet cover usually has a adjustable slider. This is the EPlus ATU:..:uncontrolled.
=======================
If you need to study the temperature in the house, then divide the floor area into more zones as the 5Zone exmple model, or in actual room divisions. Rooms without a hot air outlet would be a passive zone. Heating can be assumed to be by wall conduction or with some zone air mixing from the other rooms.
How the air is returned from each zone to the furnace is not very emportant. With a constant volume fan, a fixed fraction of this volume enters a zone, and the same amount leave the zone at a different temperature. This heat balance or difference causes the zone temperature to be slightly above or below the controlled AHU supply air temperature.
==================
Full Airflow network is designed to work
Hello All,
I have been trying for some time to model a type of residential house which uses a simple gas furnace for heating.
Heated air from the furnace passes through ducts to the simple delivery terminals (AirTerminal:SingleDuct:Uncontrolled) in each room.
There are no return air terminals in the rooms. In the real house, the air flows from the rooms through doorways and is collected at a single return vent (usually in a hall) and then through a duct back to the inlet of the furnace.
The house cannot be modelled as a single zone since important temperature differences between rooms do occur in practice.
Is there a "right" way to model this in EnergyPlus?
I have made the hall zone a return plenum for all the room zones but that is not really what plenums are for.
In addition if I use a plenum I cannot find documentation or examples on how to handle it in an airflow network so that I can correctly include the airflow through the doors.
Any guidance would be greatly appreciated.
Thanks, Andrew
I have been trying for some time to model a type of residential house which uses a simple gas furnace for heating.
Heated air from the furnace passes through ducts to the simple delivery terminals (AirTerminal:SingleDuct:Uncontrolled) in each room.
There are no return air terminals in the rooms. In the real house, the air flows from the rooms through doorways and is collected at a single return vent (usually in a hall) and then through a duct back to the inlet of the furnace.
The house cannot be modelled as a single zone since important temperature differences between rooms do occur in practice.
Is there a "right" way to model this in EnergyPlus?
I have made the hall zone a return plenum for all the room zones but that is not really what plenums are for.
In addition if I use a plenum I cannot find documentation or examples on how to handle it in an airflow network so that I can correctly include the airflow through the doors.
Any guidance would be greatly appreciated.
Thanks, Andrew
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