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Good Afternoon,
Now, I'm using a vertical storage tank Type 534-NoHxs, I just wanted to know how the initial temperature of the tank is calculated as it is larger than the average temperature of the inlet port temperatures, at the first timestep the temperature equals to 45 C while the inputs is 288 K and 228 K, so it's average is -15 C and how can i set the initial conditions for the tank?
Gehad, the fields on the "derivatives" tab allow you to set the initial temperature of each node in the tank. A "derivative" in a Trnsys Type is the initial value of something that the Type otherwise calculates as an output. Sometimes you will find a parameter that asks for the initial value of something but technically those should be derivatives as well.
David
Gehad Azmy Topic starter
12/03/2025 12:51 pm
@davidbradley so it depends on what? I need to store a cold fluid as I'm working on liquid air cycle, and I'm using propane as fluid to cool the air, so temperature of propane that I need is about 90 K, , but it is around 300 K in the model, how to change it?
@gehadrabee24 I am not sure I understand your question. To set the initial temperature of the tank you open the tank model's proforma, switch to the "derivatives" tab and enter the initial temperature. If the component you are using does not have a "derivatives" tab or if the derivatives tab is empty then look for a parameter that asks for the tank's initial temperature.
david
