[TRNSYS-users] Utilizing water draw forcing function

[mcdowell at tess-inc.com]

Ayoola - 

If you want a step change in your profile you need to
include an ending point for each period as well. See the "Begin" example
project for an example of a Type 14 schedule. 

Also your timestep will
need to be at a maximum the size of your smallest schedule step. In your
set-up you have the draw lasting 0.083 hours, so your timestep needs to
be no bigger than 0.083 hours. 

Trying creating a project with just a
Type 14 and looking at the output on the on-line plotter until you get
the output to look like you want the draw schedule to look. 

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 2013-10-31 09:26, afolayan ayoola wrote: 

>
hello, 
> I am modeling a solar domestic water heating system. I want to
create a scenerio whereby certain amount of water(like 21L) will be
drawn from a tank of 121L at a particular time (say 7am) at a flowrate
of 300kg/hr and also 42L of water is being drawn again from the tank at
7pm in the night with the same flowrate. I connected the type 14b
forcing function output to the inlet flowrate of the tank to control how
the water is being used. I run the simulation for 2 days in January with
a simulation timestep of 1hr. The draw rate and length of draw was
specified (type14b) and the last point was set at 24hrs. The result am
getting is not even close to what i was expecting because it seems the
water is being used continously. Please i will like to know what am
doing wrong. 
> I have attached the captured image of my component setup
and simulation graph for your referal. 
> Thank You 
> Best Regards 
>
Ayoola Afolayan 
> 
> On Friday, October 25, 2013 11:02 PM, Jeff
Thornton wrote:
> 
> Use a Type 14 forcing function and specify the draw
rate and length of 
> draw. Make sure to close the cycle out (the last
point should be at 24 
> hours so it repeats every 24 hours. Then
connect the output from Type 
> 14 to the inlet flow rate for the inlet
port and you're ready to go.
> 
> Jeff
> 
> ---
> 
> On 10/25/2013 2:15
am, Ayoola Afolayan wrote:
> 
>>> Hello Everyone,
>>> I am modelling a
solar domestic water 
>>> heating system using the following component:
Pump(type 3b), 
>>> Controller (type 2b), Collector (type 1b), tank
(type 4a) and weather 
>>> on TRNSYS 16. I want to determine the volume
of water that is being 
>>> drawn from a storage tank for example: 24L
of water drawn from a 
>>> storage tank of 120L capacity at 7am and the
same volume of water 
>>> drawn at 9am. I will like to know which
component in TRNSYS can 
>>> perform this task and how? 
>>> 
> 
>
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