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Hi guys, I have to model a DHW loop with a recirculation system in EnergyPlus but I encountered a big problem while modeling this situation. Below you can see the features of my problem:

1 - Real situation:

• Water from the mains at 10°C enters a stratified tank, being heated to 70°C;

• Water from the recirculation loop at 55°C bypasses the tank, then is mixed with water at 70°C and 10°C to obtain the requested flow at 60°C for the users.

2 - E+ model:

• (V) Requested flow for the users is still at 60°C;
• (V) Water outlet temperature from the tank is still 70°C;
• (X) Water inlet temperature is between 10°C and 55°C because E+ mixes recirculation and mains flows just after the users component to have a correct mass balance on the demand side of the loop.

Recirculation and mains flows mixing before the inlet node of the tank creates a problem for me because I want to evaluate water temperature in all the tank's layers and obviously the inlet water temperature greatly affects this aspect of the system. So I ask you if there is a way to model the DHW loop without having this mixing of the two flows of water.

Hi guys, I have to model a DHW loop with a recirculation system in EnergyPlus but I encountered a big problem while modeling this situation. Below you can see the features of my problem:

1 - Real situation:

• Water from the mains at 10°C enters a stratified tank, being heated to 70°C;

• Water from the recirculation loop at 55°C bypasses the tank, then is mixed with water at 70°C and 10°C to obtain the requested flow at 60°C for the users.

2 - E+ model:

• (V) Requested flow for the users is still at 60°C;
• (V) Water outlet temperature from the tank is still 70°C;
• (X) Water inlet temperature is between 10°C and 55°C because E+ mixes recirculation and mains flows just after the users component to have a correct mass balance on the demand side of the loop.

Recirculation and mains flows mixing before the inlet node of the tank creates a problem for me because I want to evaluate water temperature in all the tank's layers and obviously the inlet water temperature greatly affects this aspect of the system. So I ask you if there is a way to model the DHW loop without having this mixing of the two flows of water.

Hi guys, I have to model a DHW loop with a recirculation system in EnergyPlus but I encountered a big problem while modeling this situation. Below you can see the features of my problem:

1 - Real situation:

• Water from the mains at 10°C enters a stratified tank, being heated to 70°C;

• Water from the recirculation loop at 55°C bypasses the tank, then is mixed with water at 70°C and 10°C to obtain the requested flow at 60°C for the users.

2 - E+ model:

• (V) Requested flow for the users is still at 60°C;
• (V) Water outlet temperature from the tank is still 70°C;
• (X) Water inlet temperature is between 10°C and 55°C because E+ mixes recirculation and mains flows just after the users component to have a correct mass balance on the demand side of the loop.

Recirculation and mains flows mixing before the inlet node of the tank creates a problem for me because I want to evaluate water temperature in all the tank's layers and obviously the inlet water temperature greatly affects this aspect of the system. So I ask you if there is a way to model the DHW loop without having this mixing of the two flows of water.

Hi guys, I have to model a DHW loop with a recirculation system in EnergyPlus but I encountered a big problem while modeling this situation. Below you can see the features of my problem:

1 - Real situation:

• Water from the mains at 10°C enters a stratified tank, being heated to 70°C;

• Water from the recirculation loop at 55°C bypasses the tank, then is mixed with water at 70°C and 10°C to obtain the requested flow at 60°C for the users.

2 - E+ model:

• (V) Requested flow for the users is still at 60°C;
• (V) Water outlet temperature from the tank is still 70°C;
• (X) Water inlet temperature is between 10°C and 55°C because E+ mixes recirculation and mains flows just after the users component to have a correct mass balance on the demand side of the loop.

Recirculation and mains flows mixing before the inlet node of the tank creates a problem for me because I want to evaluate water temperature in all the tank's layers and obviously the inlet water temperature greatly affects this aspect of the system. So I ask you if there is a way to model the DHW loop without having this mixing of the two flows of water.

EDIT: to help understanding my situation here it is the plant scheme I have to model:

1. The recirculation loop is essentially the orange rectangle with inlet temperature of 60°C and outlet one of 55°C (heat loss is present due to considering non adiabatic pipes);
2. Instead of what I have said before (my fault) water from the recirculation loop doesn't always bypass the tank, in fact it can be reheated if necessary to mantain the setpoint temperature of 60°C for the users.

Hi guys, I have to model a DHW loop with a recirculation system in EnergyPlus but I encountered a big problem while modeling this situation. Below you can see the features of my problem:

1 - Real situation:

• Water from the mains at 10°C enters a stratified tank, being heated to 70°C;

• Water from the recirculation loop at 55°C bypasses the tank, then is mixed with water at 70°C and 10°C to obtain the requested flow at 60°C for the users.

2 - E+ model:

• (V) Requested flow for the users is still at 60°C;
• (V) Water outlet temperature from the tank is still 70°C;
• (X) Water inlet temperature is between 10°C and 55°C because E+ mixes recirculation and mains flows just after the users component to have a correct mass balance on the demand side of the loop.

Recirculation and mains flows mixing before the inlet node of the tank creates a problem for me because I want to evaluate water temperature in all the tank's layers and obviously the inlet water temperature greatly affects this aspect of the system. So I ask you if there is a way to model the DHW loop without having this mixing of the two flows of water.

EDIT: to help understanding my situation here it is the plant scheme I have to model:

1. The recirculation loop is essentially the orange rectangle with inlet temperature of 60°C and outlet one of 55°C (heat loss is present due to considering non adiabatic pipes);
2. Instead of what I have said before (my fault) water from the recirculation loop doesn't always bypass the tank, in fact it can be reheated if necessary to mantain the setpoint temperature of 60°C for the users.