1、14.1CHAPTER 14CLIMATIC DESIGN INFORMATIONClimatic Design Conditions. 14.1Calculating Clear-Sky Solar Radiation . 14.8Transposition to Receiving Surfaces of Various Orientations 14.10Generating Design-Day Data 14.12Estimation of Degree-Days 14.12Representativeness of Data and Sources of Uncertainty .
2、 14.13Other Sources of Climatic Information 14.16HIS chapter and the data on the accompanying CD-ROM pro-Tvide the climatic design information for 8118 locations in theUnited States, Canada, and around the world. This is an increase of1675 stations from the 2013 ASHRAE HandbookFundamentals.As in the
3、 previous edition, the large number of stations made print-ing the whole tables impractical. Consequently, the complete tableof design conditions for only Atlanta, GA, appears in this printedchapter to illustrate the table format. However, a subset of the tableelements most often used is presented i
4、n the Appendix at the end ofthis chapter for selected stations representing major urban centers inthe United States, Canada, and around the world. The complete datatables for all 8118 stations are contained on the CD-ROM thataccompanies this book.This climatic design information is commonly used for
5、 design,sizing, distribution, installation, and marketing of heating, ventilat-ing, air-conditioning, and dehumidification equipment, as well as forother energy-related processes in residential, agricultural, commer-cial, and industrial applications. These summaries include values ofdry-bulb, wet-bu
6、lb, and dew-point temperature, and wind speed withdirection at various frequencies of occurrence. Also included aremonthly degree-days to various bases, parameters to calculate clear-sky irradiance, and monthly averages of daily all-sky solar radiation.Sources of other climate information of potenti
7、al interest toASHRAE members are described later in this chapter.Design information in this chapter was developed largely throughresearch project RP-1699 (Roth 2017). The information includesdesign values of dry-bulb with mean coincident wet-bulb tempera-ture, design wet-bulb with mean coincident dr
8、y-bulb temperature,and design dew-point with mean coincident dry-bulb temperatureand corresponding humidity ratio. These data allow the designer toconsider various operational peak conditions. Design values of windspeed facilitate the design of smoke management systems in build-ings (Lamming and Sal
9、mon 1996, 1998).Warm-season temperature and humidity conditions are based onannual percentiles of 0.4, 1.0, and 2.0. Cold-season conditions arebased on annual percentiles of 99.6 and 99.0. The use of annual per-centiles to define design conditions ensures that they represent thesame probability of o
10、ccurrence in any climate, regardless of the sea-sonal distribution of extreme temperature and humidity.Monthly precipitation data are also included. They are usedmostly to determine climate zones for ASHRAE Standard 169, butmay also be helpful in developing green technologies such as vege-tative roo
11、fs.The clear-sky solar radiation model introduced in the 2009 edi-tion and slightly modified in the 2013 edition is unchanged in itsgeneral formulation. However, the site-specific coefficients havebeen recalculated, based on the latest atmospheric information avail-able. Additionally, all-sky solar
12、radiation values have been added;these are useful in assessing solar technologies (solar heating, pho-tovoltaics), which are typically necessary in the quest for designingnet-zero buildings.Design conditions are provided for locations for which long-termhourly observations were available (1990-2014
13、for most stations inthe United States and Canada). Compared to the 2013 chapter, thenumber of U.S. stations increased from 1406 to 1952 (39% increase);Canadian stations increased from 562 to 765 (36% increase); andstations in the rest of the world increased from 4475 to 5401 (21% in-crease; see Figu
14、re 1 for map).1. CLIMATIC DESIGN CONDITIONSTable 1 shows climatic design conditions for Atlanta, GA, toillustrate the format of the data available on the CD-ROM. A limitedsubset of these data for 1445 of the 8118 locations for 21 annual dataelements is provided for convenience in the Appendix.The to
15、p part of the table contains station information as follows: Name of the observing station, state (USA) or province (Canada),country.World Meteorological Organization (WMO) station identifier.Weather Bureau Army Navy (WBAN) number (99999 denotesmissing).Latitude of station, N/S.Longitude of station,
16、 E/W.Elevation of station, m.Standard pressure at elevation, in kPa (see Chapter 1 for equationsused to calculate standard pressure).Time zone, h UTC.Time zone code (e.g., NAE = Eastern Time, USA and Canada). TheCD-ROM contains a list of all time zone codes used in the tables.Period analyzed (e.g.,
17、90-14 = data from 1990 to 2014 were used).Annual Design ConditionsAnnual climatic design conditions are contained in the first threesections following the top part of the table. They contain informationas follows:Annual Heating and Humidification Design Conditions.Coldest month (i.e., month with low
18、est average dry-bulb tempera-ture; 1 = January, 12 = December).Dry-bulb temperature corresponding to 99.6 and 99.0% annualcumulative frequency of occurrence (cold conditions), C.Dew-point temperature corresponding to 99.6 and 99.0% annualcumulative frequency of occurrence, C; corresponding humidityr
19、atio, calculated at standard atmospheric pressure at elevation ofstation, grams of moisture per kg of dry air; mean coincident dry-bulb temperature, C.Wind speed corresponding to 0.4 and 1.0% cumulative frequencyof occurrence for coldest month, m/s; mean coincident dry-bulbtemperature, C.Mean wind s
20、peed coincident with 99.6% dry-bulb temperature,m/s; corresponding most frequent wind direction, degrees fromnorth (east = 90).Annual Cooling, Dehumidification, and Enthalpy Design Con-ditions.Hottest month (i.e., month with highest average dry-bulb tempera-ture; 1 = January, 12 = December).The prep
21、aration of this chapter is assigned to TC 4.2, Climatic Information.14.2 2017 ASHRAE HandbookFundamentals (SI)Daily temperature range for hottest month, C defined as mean ofthe difference between daily maximum and daily minimum dry-bulb temperatures for hottest month.Dry-bulb temperature correspondi
22、ng to 0.4, 1.0, and 2.0% annualcumulative frequency of occurrence (warm conditions), C; meancoincident wet-bulb temperature, C.Wet-bulb temperature corresponding to 0.4, 1.0, and 2.0% annualcumulative frequency of occurrence, C; mean coincident dry-bulb temperature, C.Mean wind speed coincident with
23、 0.4% dry-bulb temperature,m/s; corresponding most frequent wind direction, degrees truefrom north (east = 90).Dew-point temperature corresponding to 0.4, 1.0, and 2.0%annual cumulative frequency of occurrence, C; correspondinghumidity ratio, calculated at the standard atmospheric pressure atelevati
24、on of station, grams of moisture per kg of dry air; meancoincident dry-bulb temperature, C.Enthalpy corresponding to 0.4, 1.0, and 2.0% annual cumulativefrequency of occurrence, kJ/kg; mean coincident dry-bulb tem-perature, C.Extreme maximum wet-bulb temperature, C.Extreme Annual Design Conditions.W
25、ind speed corresponding to 1.0, 2.5, and 5.0% annual cumula-tive frequency of occurrence, m/s.Mean and standard deviation of extreme annual minimum andmaximum dry-bulb temperature, C.5-, 10-, 20-, and 50-year return period values for minimum andmaximum extreme dry-bulb temperature, C.Mean and standa
26、rd deviation of extreme annual minimum andmaximum wet-bulb temperature, C.5-, 10-, 20-, and 50-year return period values for minimum andmaximum extreme wet-bulb temperature, C.Monthly Design ConditionsMonthly design conditions are divided into subsections as fol-lows:Temperatures, Degree-Days, and D
27、egree-Hours.Average temperature, C. This parameter is a prime indicator ofclimate and is also useful to calculate heating and cooling degree-days to any base.Standard deviation of average daily temperature, C. This param-eter is useful to calculate heating and cooling degree-days to anybase. Its use
28、 is explained in the section on Estimation of Degree-Days.Heating and cooling degree-days (bases 10 and 18.3C). Theseparameters are useful in energy estimating methods. They are alsoused to classify locations into climate zones in ASHRAE Stan-dard 169.Cooling degree-hours (bases 23.3 and 26.7C). The
29、se are used invarious standards, such as Standard 90.2-2004.Wind.Monthly average wind speed, m/s. This parameter is useful toestimate the wind potential at a site; however, the local topogra-phy may significantly alter this value, so close attention is needed.Precipitation.Average precipitation, mm.
30、 This parameter is used to calculateclimate zones for Standard 169, and is of interest in some greenbuilding technologies (e.g., vegetative roofs).Standard deviation of precipitation, mm. This parameter indicatesthe variability of precipitation at the site.Minimum and maximum precipitation, mm. Thes
31、e parametersgive extremes of precipitation and are useful for green buildingtechnologies and stormwater management.Monthly Design Dry-Bulb, Wet-Bulb, and Mean CoincidentTemperatures.These values are derived from the same analysis that results inthe annual design conditions. The monthly summaries are
32、 usefulwhen seasonal variations in solar geometry and intensity, buildingor facility occupancy, or building use patterns require consider-ation. In particular, these values can be used when determiningFig. 1 Locations of Weather StationsClimatic Design Information 14.3air-conditioning loads during p
33、eriods of maximum solar radiation.The values listed in the tables includeDry-bulb temperature corresponding to 0.4, 2.0, 5.0, and 10.0%cumulative frequency of occurrence for indicated month, C;mean coincident wet-bulb temperature, C.Wet-bulb temperature corresponding to 0.4, 2.0, 5.0, and 10.0%cumul
34、ative frequency of occurrence for indicated month, C;mean coincident dry-bulb temperature, C.For a 30-day month, the 0.4, 2.0, 5.0 and 10.0% values of occur-rence represent the value that occurs or is exceeded for a total of 3,14, 36, or 72 h, respectively, per month on average over the periodof rec
35、ord. Monthly percentile values of dry- or wet-bulb tempera-ture may be higher or lower than the annual design conditions cor-responding to the same nominal percentile, depending on themonth and the seasonal distribution of the parameter at that loca-tion. Generally, for the hottest or most humid mon
36、ths of the year,the monthly percentile value exceeds the design condition for thesame element corresponding to the same nominal percentile. Forexample, Table 1 shows that the annual 0.4% design dry-bulb tem-perature at Atlanta, GA, is 34.4C; the 0.4% monthly dry-bulb tem-perature exceeds 34.4C for J
37、une, July, and August, with values of34.7, 36.4, and 36.3C, respectively. Fifth and tenth percentiles arealso provided to give a greater range in the frequency of occur-rence, in particular providing less extreme options to select fordesign calculations.A general, very approximate rule of thumb is t
38、hat the n% annualcooling design condition is roughly equivalent to the 5n% monthlycooling condition for the hottest month; that is, the 0.4% annualdesign dry-bulb temperature is roughly equivalent to the 2%monthly design dry-bulb temperature for the hottest month; the 1%annual value is roughly equiv
39、alent to the 5% monthly value for thehottest month, and the 2% annual value is roughly equivalent to the10% monthly value for the hottest month.Mean Daily Temperature Range. These values are useful incalculating daily dry- and wet-bulb temperature profiles, as ex-plained in the section on Generating
40、 Design-Day Data. Three kindsof profile are defined:Mean daily temperature range for month indicated, C (defined asmean of difference between daily maximum and minimum dry-bulb temperatures).Mean daily dry- and wet-bulb temperature ranges coincident withthe 5% monthly design dry-bulb temperature. Th
41、is is the differ-ence between daily maximum and minimum dry- or wet-bulbtemperatures, respectively, averaged over all days where the max-imum daily dry-bulb temperature exceeds the 5% monthly designdry-bulb temperature.Mean daily dry- and wet-bulb temperature ranges coincident withthe 5% monthly des
42、ign wet-bulb temperature. This is the differ-ence between daily maximum and minimum dry- or wet-bulbtemperatures, respectively, averaged over all days where the max-imum daily wet-bulb temperature exceeds the 5% monthly designwet-bulb temperature.Clear-Sky Solar Irradiance. Clear-sky irradiance para
43、metersare useful in calculating solar-related air conditioning loads for anytime of any day of the year. Parameters are provided for the 21st dayof each month. The 21st of the month is usually a convenient day forsolar calculations because June 21 and December 21 represent thesolstices (longest and
44、shortest days) and March 21 and September21 are close to the equinox (days and nights have the same length).Parameters listed in the tables areClear-sky optical depths for beam and diffuse irradiances, whichare used to calculate beam and diffuse irradiance as explained inthe section on Calculating C
45、lear-Sky Solar Radiation.Clear-sky beam normal and diffuse horizontal irradiances at solarnoon. These two values can be calculated from the clear-sky opti-cal depths but are listed here for convenience.All-Sky Solar Radiation. All-sky solar radiation parameters areuseful for evaluating the potential
46、 of solar technologies (e.g., solarheating, photovoltaics), which are valuable in the design of net-zeroenergy buildings. Parameters listed in the tables areMonthly average daily global radiation on a horizontal surface.This is a traditional way to characterize the solar resource at a site.Standard
47、deviation of monthly average daily radiation on a hori-zontal surface. This parameter gives an idea of the year-to-yearvariability of the solar resource at the site.Data SourcesThe following primary sources of observational data sets wereused in calculating design values:For most Canadian stations,
48、meteorological data were obtaineddirectly from Environment Canada (climate.weather.gc.ca) forthe years 1982-2014.Data were obtained from the U.S. Climate Reference Network(CRN) (www.ncdc.noaa.gov/crn) (Diamond et al. 2013).Most stations, including some in Canada with inadequate data,were sourced thr
49、ough the Integrated Surface Database (ISD) fromNOAA (www.ncdc.noaa.gov) (Smith et al. 2011) for the years1982-2015.In most cases, the period of record used in the calculationsspanned 25 years (1990 to 2014). This choice of period is a com-promise between trying to derive design conditions from the lon-gest possible period of record, and using the most recent data tocapture climatic or land-use trends from the past two decades. Theactual number of years used in the calculations for a given stationdepends on the amount of missing data, and, as discussed
