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psychrometric function Openstudio SDK

asked 2016-01-26 13:39:33 -0600

ngkhanh gravatar image

hello, Is there any method to implement Psychrometric chart in Openstudio measure like EMS psy. function in E+ ? Even a method to link with an external source is ok.

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answered 2016-01-26 14:21:50 -0600

updated 2016-01-26 14:24:24 -0600

@aparker has implemented a psych chart as a reporting measure. Here's what it looks like:

image description

The gray box at the bottom is interactive and allows you to filter the results based on period of time. I've pinged him for info on what repo it lives in, and I will update this post with that information when he gets back to me.

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@ngkhanh the Measure to create this chart is now available on BCL here. You can also download it via the app: Components & Measures > Find Measures > Reporting >Troubleshooting > HVAC Psychrometric Chart.

aparker gravatar image aparker  ( 2016-02-11 17:14:52 -0600 )edit

@aparker Thank alot. The chart html file is very heavy. I will modify a little so that it shows only key points (10 -20 points only). But is there the way to connect 2 point in the psychart like ASHRAE psychart program ?? In your experiences, Which brower is best for open that heavy html file ?

ngkhanh gravatar image ngkhanh  ( 2016-02-11 18:12:29 -0600 )edit

Yeah, the file is heavy. Because it is including 8760 values * 2 values (temp, humidity) for each node * # nodes. Chrome browser works best for me.

Yes, it is possible to connect the points. The chart is made with a very complex but flexible graphing packaged called D3.js. There are tons of examples online, which is how I blundered through it. The first thing you'd probably want to do is modify to just show a single point in time, then add the code to connect the points. This is on my personal wish list, but don't have time to figure it out at the moment.

aparker gravatar image aparker  ( 2016-02-11 18:47:02 -0600 )edit

the measure doesn't work with me, i keep getting errors when applying the measure!! what do i need to cal the air Loop name?

shahin1992 gravatar image shahin1992  ( 2016-05-27 00:00:19 -0600 )edit

answered 2016-01-26 16:51:36 -0600

updated 2016-01-26 16:51:53 -0600

@Jason DeGraw has also implemented some pretty cool stuff in the EpwFile class that has not gotten a lot of press yet. The getTimeSeries and getComputedTimeseries methods of EpwFile can be used to get information like 'DryBulbTemperature' or 'AtmosphericStationPressure' out of the EpwFile as a OpenStudio TimeSeries object. There is also an AirState class that can do some basic psychrometric calculations.

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Note that this was added after Andrew wrote his pysch chart measure so I don't think the reporting measure uses these functions.

macumber gravatar image macumber  ( 2016-01-26 16:53:01 -0600 )edit

thank they are really cool functions. How i can get Psychometric chart measure ?

ngkhanh gravatar image ngkhanh  ( 2016-01-26 21:27:47 -0600 )edit

I implemented the AirState stuff as part of a project I was working on, so it might be missing features that I didn't need. Let me know if that is the case.

Jason DeGraw gravatar image Jason DeGraw  ( 2016-02-08 11:56:55 -0600 )edit

@Jason DeGraw : i want to made interactive Psychometric chart with AirState function for demonstration cooling process. Have you had any measure with psychrometric chart ?

ngkhanh gravatar image ngkhanh  ( 2016-02-11 11:06:37 -0600 )edit

I haven't done that specifically, but it should be possible. Some parts of AirState are pretty lightly tested, so calculations that we can use for testing are highly desirable.

Jason DeGraw gravatar image Jason DeGraw  ( 2016-02-11 12:12:06 -0600 )edit

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Asked: 2016-01-26 13:39:33 -0600

Seen: 369 times

Last updated: Jan 26 '16