need to determine the outdoor design conditions 1

[condizionamento]

I need to determine the outdoor design conditions for HVAC system on board of CRUISE SHIPS.

I got hourly weather data from NOAA including air temperature, relative humidity and sea surface temperature for a large number of buoys in the TROPICAL OCEAN ( 1996 - 2007 ).

Does anyone know how to determine the outdoor design conditions from the statisycal analysis of hourly climatic data?

Thanks for any help.

 

[MintJulep]

I'm sure I could get that information for you.

I'd just need a few years of field research.

 

[AbbyNormal]

I would say your dewpoint will be about 80F and your dry bulb temperatue in the rainy season may hit 90 to 92

Take the "V" out of HVAC and you are left with a HAC(k) job.

 

[KiwiMace]

Why not use the ports, or the worst case of nearest ports to the sailing route.

You can sort the data, scale 0 - 100% then get the 2% figure from the 98% highest temp and coincident wetbulb/RH. Do this for each of the years and average the numbers.
I'd still compare this to the ports.

 

[AbbyNormal]

land will be hotter, lower RH, just make sure you can handle the big dewpoint and you will be golden. Take it from a guy on a small tropical island

Take the "V" out of HVAC and you are left with a HAC(k) job.

 

[vpl]

I am moving this over from one of your other identical posts so it doesn't get lost.

You are looking at a daunting task...

Solar exposure thru windows can can change the exposed area heat loads many times, (4-6x), more than just heat leakage loads.

You need to do the standard heat load calculations:
Heat gain thru the walls.
Heat gain thru exterior ceilings.
Heat gain thru the floors into hot spaces like kitchens or mechanical spaces.
Heat gain due to people.
Heat gain due to electrical consumption.
Then the aforementioned solar gain.

All this varies from floor to floor and from outside spaces to inner spaces.

Keith Cress
kcress -

http://www.flaminsystems.com

Patricia Lougheed

Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of the Eng-Tips Forums.

 

[condizionamento]

OK KiwiMace.

And what about sea surface temperature?

Thank you

 

[quark]

Patricia,

Just for your information, the reply you alluded to is not in line with the OP's question. The OP says he has the hourly weather data and he requires to get the outside design conditions. Though this task is not simple, it can be done with patience.

Like KiwiMace suggested, one has to calculate the cumilative frequency of occurance of DBT (or/and WBT) and calculate the corresponding mean coincidental WBT (or/and DBT). The standard convention is to select from 0.4%, 1% or 2% exceeding values depending upon the redundancy (of the enthalpy at the selected condition) level required during heat load calculation.

Regards,

 

[AbbyNormal]

You may find that the sea surface temperatures correlates with the dew point temperature.

The usual problems I find with designs by engineers in the UK , Canada and the USA for my little island (with no published design conditions) is they do not properly account for the dewpoint of the ambient air, and they also tend to only consider the effect of the sun in July/August.

At least with a building orientations of windows are fixed.




Take the "V" out of HVAC and you are left with a HAC(k) job.

 

[KiwiMace]

"what about the sea surface temp?" you tell us - you're the one with both sets of data. You are in a great position of being able to verify readily available and properly formatted data with another set of data that is specific to your application.

Is the sea surface temp even relevant to the goings-on on the top deck of a cruise ship. This is high enough to have a climate of its own. Most of SE Asia [and all of AbbyNormal's little island] would be below this height above sea level.

 

[AbbyNormal]

sometimes they build buildings that need elevators

does the sea temperature explain why scotland is warmer than minnesota?

Take the "V" out of HVAC and you are left with a HAC(k) job.