SWHS - Volume of PCM software constraint

[JacquesCarette]

Stable contains the following non-sensical constraint:
Physical: 0 < V_P < V_{tank}
Software: V_P >= V_{tank}

so the software constraint and the physical constraint have no overlap.

[smiths]

These constraints do not match the information in the original case study (https://github.com/smiths/swhs/blob/master/SRS/PCM_SRS.pdf page 23). This is another example of a translation error from "manual" to Drasil code. The Drasil physical constraint matches the case study, but the Drasil software constraint was originally:

V_P >= MINFRACT*V_{tank}, where MINFRACT was set to 10^{-6} in the original case study. MINFRACT is a symbolic constant in Table 2 (Specification Parameter Values). To avoid the problem you noticed, we should constrain MINFRACT to be less than 1.

[JacquesCarette]

Right - so you've "fixed" the part that needed your expertise to fix. Now there is an issue in the Drasil version of SWHS that should also be fixed. Have we sort-of assigned some of the projects to our M.Eng. students, so that I could re-assign this?

[smiths]

@halonazhao, has been working with the SWHS example; therefore, I will reassign this issue to her. Yuzhi, please modify the Drasil code for the SWHS example to match the case study example for the V_P constraint. If you have any questions about the constraint, please ask me. For questions about the changes to the Drasil code, please ask @szymczdm.

[halonazhao]

Hello @szymczdm
I just updated the version to fix this issue 53f705b. The tex file and html file work. But still there are two ignored errors. I don't know what happened cause there is no detailed information. Those two are not the same errors from the Nopcm case because I commented the SSD section out in Nopcm. Can you please take a look?

[halonazhao]

@smiths Could you give me a specific definition, unit and value for variable minfract? In manual version now, there is no statement for this variable any more. I guess we put minfract in Values of Auxiliary Constants table? Since you mentioned that this value should be less than 1 , which is a range, but in Values of Auxiliary Constants table, every constant has a specific value. Is that ok I directly put 10^-6 as you ever mentioned?

Thanks!

[smiths]

MINFRACT is in the manual (case study) version of SWHS. Maybe your search is case sensitive? MINFRACT is a constant, so the typographic convention is used where it is displayed in ALL_CAPS. As you said, MINFRACT is in the table of Auxiliary Constants and has a value of 1e-6. MINFRACT is unitless. In case it isn't clear, MINFRACT is the minimum fraction of the volume of the PCM to the volume of the tank. Dividing units of volume by units of volume means that MINFRACT is unitless.

[halonazhao]

Issue has been solved in e9a0fff