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I could be overruled here and I'm assuming we are talking about "Detailed" HVAC timestep level report variables in EnergyPlus. The temperature and flow that is reported at the node (presumably we are talking about nodes after DX coils, but it doesn't really matter) represent the actual temperature and flow that the simulation is feeding into the zone. There is no averaging of any kind unless we are talking about report variables at the zone timestep or longer frequency. Flow is determined by the requests from the demand side terminals. A target temperature is established by a setpoint manager (often SetpointMangerSingleZoneReheat for packaged units where RTF applies), and the DX coil attempts to hit that setpoint by figuring out what fraction of its capacity (RTF) would be needed to hit that temperature at the already established flow rate. Most DX equipment has limited ability to part load and meet a particular node (supply) temperature, but the simulation isn't modeling reality. It just degrades the coil's performance using an empirical correlation involving the RTF. SetpointMangerSingleZoneReheat in particular computes a variable supply temperature to hit a particular zone's load at the system's current air flow rate, even though a real system would simply be cycling on and off to meet the zone load.

It is possible to use EnergyPlus's EMS feature combined with very short time steps to model real cycling, but you won't get that out of the box with EnergyPlus, and I'd say it is still a research project.

I could be overruled here and I'm assuming we are talking about "Detailed" HVAC timestep level report variables in EnergyPlus. The temperature and flow that is reported at the node (presumably we are talking about nodes after DX coils, but it doesn't really matter) represent the actual temperature and flow that the simulation is feeding into the zone. There is no averaging of any kind unless we are talking about report variables at the zone timestep or longer frequency. Flow is determined by the requests from the demand side terminals. A target temperature is established by a setpoint manager (often SetpointMangerSingleZoneReheat for packaged units where RTF applies), and the DX coil attempts to hit that setpoint by figuring out what fraction of its capacity (RTF) would be needed to hit that temperature at the already established flow rate. Most DX equipment has limited ability to part load and meet a particular node (supply) temperature, but the simulation isn't modeling reality. It just degrades the coil's performance using an empirical correlation involving the RTF. SetpointMangerSingleZoneReheat in particular computes a variable supply temperature to hit a particular zone's load at the system's current air flow rate, even though a real system would simply be cycling on and off to meet the zone load.

It is possible to use EnergyPlus's EMS feature combined with very short time steps to model real cycling, but you won't get that out of the box with EnergyPlus, and I'd say it is still a research project.project. For one thing you don't capture the latent degradation when you do this.

I could be overruled here and I'm assuming we are talking about "Detailed" HVAC timestep level report variables in EnergyPlus. The temperature and flow that is reported at the node (presumably we are talking about nodes after DX coils, but it doesn't really matter) represent the actual temperature and flow that the simulation is feeding into the zone. There is no averaging of any kind unless we are talking about report variables at the zone timestep or longer frequency. Flow is determined by the requests from the demand side terminals. A target temperature is established by a setpoint manager (often SetpointMangerSingleZoneReheat for packaged units where RTF applies), and the DX coil attempts to hit that setpoint by figuring out what fraction of its capacity (RTF) would be needed to hit that temperature at the already established flow rate. Most DX equipment has limited ability to part load and meet a particular node (supply) temperature, but the simulation isn't modeling reality. It just degrades the coil's performance using an empirical correlation involving the RTF. SetpointMangerSingleZoneReheat in particular computes a variable supply temperature to hit a particular zone's load at the system's current air flow rate, even though a real system would simply be cycling on and off to meet the zone load.

It is possible to use EnergyPlus's EMS feature combined with very short time steps to model real cycling, but you won't get that out of the box with EnergyPlus, and I'd say it is still a research project. For one thing you don't capture the latent degradation when you do this.

Averaging is going to happen for temperature and flow if you view report variables above the "Detailed" reporting frequency.frequency. There is some ambiguity as to what the correct temperature is for time steps when there is no zero flow. I believe that EnergyPlus will just carry over the previous timestep value.

I could be overruled here and I'm assuming we are talking about "Detailed" HVAC timestep level report variables in EnergyPlus. The temperature and flow that is reported at the node (presumably we are talking about nodes after DX coils, but it doesn't really matter) represent the actual temperature and flow that the simulation is feeding into the zone. There is no averaging of any kind unless we are talking about report variables at the zone timestep or longer frequency. Flow is determined by the requests from the demand side terminals. A target temperature is established by a setpoint manager (often SetpointMangerSingleZoneReheat for packaged units where RTF applies), and the DX coil attempts to hit that setpoint by figuring out what fraction of its capacity (RTF) would be needed to hit that temperature at the already established flow rate. Most DX equipment has limited ability to part load and meet a particular node (supply) temperature, but the simulation isn't modeling reality. It just degrades the coil's performance using an empirical correlation involving the RTF. SetpointMangerSingleZoneReheat in particular computes a variable supply temperature to hit a particular zone's load at the system's current air flow rate, even though a real system would simply be cycling on and off to meet the zone load.

It is possible to use EnergyPlus's EMS feature combined with very short time steps to model real cycling, but you won't get that out of the box with EnergyPlus, and I'd say it is still a research project. For one thing you don't capture the latent degradation when you do this.

Averaging is going to happen for temperature and flow if you view report variables above the "Detailed" reporting frequency. There is some ambiguity as to what the correct temperature is for time steps when there is no zero flow. I believe that EnergyPlus will just carry over the previous timestep value.