Re: [TRNSYS-users] Type 2b auxiliary heater of a stratified storage tank

[mcdowell@tess-inc.com]

Rajaa -

I am not clear on what you are trying to accomplish with your model.

If you are trying to model a tank in an environment with a constant temperature, you can just set the environmental temperature inputs to the tank model to a constant 55C. 

Type 6 is intended to model the heating of a fluid stream and not the air surrounding a tank.

Regards,

Tim

---
Timothy P. McDowell
Executive Vice President
Thermal Energy System Specialists, LLC
22 N Carroll St, Suite 370
Madison, WI 53703
608-274-2577

On 2013-04-10 12:17, Rajaa Badaoui wrote:

Hi everybody,

I'm stuck with trying to control the outside temperature of a stratified storage tank (type534) with the controller type2b and the auxiliary heater type6.

When i first connect only the auxiliary heater to the tank, the auxiliary heater was ON only when there was a flow stream.

Then i connected a controller to maintain the auxiliary heater even if there is no flowrate. the outside storage tank temperature has to be always at 55°C.

But sometimes the outside temperature of the tank is lower than 55°C.

I think i put a sufficient maximum heating rate in the type6.

I connected the tank nodal temperature to the lower input temperature of the controller

I set the upper input temperature of the controller to 55°C

Can somebody help me to understand why i can't maintain the outside temperature at 55°C?

I'll be grateful for any advice

Thanks in advance

Rajaa