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Any guideline specifying the heat distribution for ElectricEquipment

asked 2017-08-25 03:51:24 -0500

katsuya.obara's avatar

updated 2017-08-25 04:24:08 -0500

I want to know whether there is any guideline specifying the heat distribution for ElectricEquipment. Especially, I want to know the percentage of Fraction Lost.

In InputOutputReference, it is described

fconvected=1.0-(Fraction Latent + Fraction Radiant + Fraction Lost)

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We have a convention to not include greetings ("Hello", "thank you", etc), thanks!

Julien Marrec's avatar Julien Marrec  ( 2017-08-25 04:23:50 -0500 )edit

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answered 2017-08-25 04:30:52 -0500

updated 2017-08-25 04:31:23 -0500

You'd typically use "Fraction Lost" that isn't zero for equipment where some of the load is - you guessed it - "lost".

See the input/output reference for Fraction Lost

This field is a decimal number between 0.0 and 1.0 and is used to characterize the amount of “lost” heat being given off by electric equipment in a zone. The number specified in this field will be multiplied by the total energy consumed by electric equipment to give the amount of heat which is “lost” and does not impact the zone energy balances. This might correspond to electrical energy converted to mechanical work or heat that is vented to the atmosphere.

Perhaps an example is an electric dryer that is vented to the outside: a (big) fraction is lost to outside. (BEOpt assumes 0.8 for example, see here)

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In a case where there is Kitchen exhaust, if you modeled the exhaust fan as zone equipment, would you assign fraction lost or leave it as this needs to be handled by the exhaust fan? What is a reasonable assumption for Kitchen cooking fraction radiant, latent and lost?

Nithya's avatar Nithya  ( 2018-04-06 09:16:34 -0500 )edit

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Asked: 2017-08-25 03:51:24 -0500

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Last updated: Aug 25 '17