1、14.1CHAPTER 14 CLIMATIC DESIGN INFORMATIONClimatic Design Conditions 14.1CALCULATING CLEAR-SKY SOLAR RADIATION. 14.7TRANSPOSITION TO RECEIVING SURFACES OF VARIOUS ORIENTATIONS. 14.10Generating Design-Day Data 14.11Estimation of Degree-Days 14.12Representativeness of Data and Sources of Uncertainty .
2、 14.13Other Sources of Climatic Information 14.15HIS chapter and the data on the accompanying CD-ROM pro-Tvide the climatic design information for 6443 locations in theUnited States, Canada, and around the world. This is an increase of879 stations from the 2009 ASHRAE HandbookFundamentals. Asin the
3、previous edition, the large number of stations made printingthe whole tables impractical. Consequently, the complete table ofdesign conditions for only Atlanta, GA, appears in this printed chap-ter to illustrate the table format. However, a subset of the table ele-ments most often used is presented
4、in the Appendix at the end of thischapter for selected stations representing major urban centers in theUnited States, Canada, and around the world. The complete datatables for all 6443 stations are contained on the CD-ROM thataccompanies this book.This climatic design information is commonly used fo
5、r 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-b
6、ulb, and dew-point temperature, and wind speed withdirection at various frequencies of occurrence. Also included in thisedition are monthly degree-days to various bases, and parameters tocalculate clear-sky irradiance. Sources of other climate informationof potential interest to ASHRAE members are d
7、escribed later in thischapter.Design information in this chapter was developed largely throughresearch project RP-1613 (Thevenard and Gueymard 2013). Theinformation includes design values of dry-bulb with mean coinci-dent wet-bulb temperature, design wet-bulb with mean coincidentdry-bulb temperature
8、, and design dew-point with mean coincidentdry-bulb temperature and corresponding humidity ratio. These dataallow the designer to consider various operational peak conditions.Design values of wind speed facilitate the design of smoke manage-ment systems in buildings (Lamming and Salmon 1996, 1998).W
9、arm-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 occurrence in any
10、climate, regardless of the sea-sonal distribution of extreme temperature and humidity.Monthly information including percentiles is compiled in addi-tion to annual percentiles, to provide seasonally representative com-binations of temperature, humidity, and solar conditions.Precipitation data have be
11、en introduced in this edition. They areused mostly to determine climate zones for ASHRAE Standard 169,but may also be helpful in developing green technologies such asvegetative roofs.Finally, the clear-sky solar radiation model introduced in the2009 edition has been slightly modified, with new coeff
12、icients usedin expressions for calculation of air mass exponents ab and ad.Design conditions are provided for locations for which long-termhourly observations were available (1986-2010 for most stations inthe United States and Canada). Compared to the 2009 chapter, thenumber of U.S. stations increas
13、ed from 1085 to 1406 (29%increase); Canadian stations increased from 480 to 562 (16%increase); and stations in the rest of the world increased from 3999to 4475 (12% increase; see Figure 1 for map).CLIMATIC DESIGN CONDITIONSTable 1 shows climatic design conditions for Atlanta, GA, toillustrate the fo
14、rmat of the data available on the CD-ROM. A limitedsubset of this data for 1445 of the 6443 locations for 21 annual dataelements is provided for convenience in the Appendix.The top part of the table contains station information as follows: Name of the observing station, state (USA) or province (Cana
15、da),country. World Meteorological Organization (WMO) station identifier. Weather Bureau Army Navy (WBAN) number (99999 denotesmissing). Latitude of station, N/S. Longitude of station, E/W. Elevation of station, ft. Standard pressure at elevation, in psia (see Chapter 1 for equationsused to calculate
16、 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., 82-06 = data from 1982 to 2006 were used).Annual Design ConditionsAnnual climatic design conditions are contai
17、ned 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 lowest average dry-bulb temper-ature; 1 = January, 12 = December). Dry-bulb temperature corresponding to 99.6 an
18、d 99.0% annualcumulative frequency of occurrence (cold conditions), F. Dew-point temperature corresponding to 99.6 and 99.0% annualcumulative frequency of occurrence, F; corresponding humidityratio, calculated at standard atmospheric pressure at elevation ofstation, grains of moisture per lb of dry
19、air; mean coincident dry-bulb temperature, F. Wind speed corresponding to 0.4 and 1.0% cumulative frequencyof occurrence for coldest month, mph; mean coincident dry-bulbtemperature, F. Mean wind speed coincident with 99.6% dry-bulb temperature,mph; corresponding most frequent wind direction, degrees
20、 fromnorth (east = 90).Annual Cooling, Dehumidification, and Enthalpy Design Con-ditions. Hottest month (i.e., month with highest average dry-bulb temper-ature; 1 = January, 12 = December). Daily temperature range for hottest month, F defined as mean ofthe difference between daily maximum and daily
21、minimum dry-bulb temperatures for hottest month.The preparation of this chapter is assigned to TC 4.2, Climatic Information.14.2 2013 ASHRAE HandbookFundamentalsTable 1 Design Conditions for Atlanta, GA, USA (see Table 1A for Nomenclature)Climatic Design Information 14.3 Dry-bulb temperature corresp
22、onding to 0.4, 1.0, and 2.0% annualcumulative frequency of occurrence (warm conditions), F; meancoincident wet-bulb temperature, F. Wet-bulb temperature corresponding to 0.4, 1.0, and 2.0% annualcumulative frequency of occurrence, F; mean coincident dry-bulb temperature, F. Mean wind speed coinciden
23、t with 0.4% dry-bulb temperature,mph; 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, F; correspondinghumidity ratio, calculated at the standard atmospheric pressure at
24、elevation of station, grains of moisture per lb of dry air; meancoincident dry-bulb temperature, F. Enthalpy corresponding to 0.4, 1.0, and 2.0% annual cumulativefrequency of occurrence, Btu/lb; mean coincident dry-bulb tem-perature, F. Number of hours between 8 AM and 4 PM (inclusive) with dry-bulb
25、temperature between 55 and 69F.Extreme Annual Design Conditions. Wind speed corresponding to 1.0, 2.5, and 5.0% annual cumula-tive frequency of occurrence, mph. Extreme maximum wet-bulb temperature, F. Mean and standard deviation of extreme annual minimum andmaximum dry-bulb temperature, F. 5-, 10-,
26、 20-, and 50-year return period values for minimum andmaximum extreme dry-bulb temperature, F.Monthly Design ConditionsMonthly design conditions are divided into subsections as fol-lows:Temperatures, Degree-Days, and Degree-Hours. Average temperature, F. This parameter is a prime indicator ofclimate
27、 and is also useful to calculate heating and cooling degree-days to any base. Standard deviation of average daily temperature, F. This param-eter is useful to calculate heating and cooling degree-days to anybase. Its use is explained in the section on Estimation of Degree-Days. Heating and cooling d
28、egree-days (bases 50 and 65F). 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 74 and 80F). These are used in var-ious standards, such as Standard 90.2-2004.Precipitation. Average
29、 precipitation, in. This parameter is used to calculate cli-mate zones for Standard 169, and is of interest in some greenbuilding technologies (e.g., vegetative roofs). Standard deviation of precipitation, in. This parameter indicatesthe variability of precipitation at the site. Minimum and maximum
30、precipitation, in. These parameters giveextremes of precipitation and are useful for green building tech-nologies 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.
31、The monthly summaries are usefulwhen seasonal variations in solar geometry and intensity, buildingor facility occupancy, or building use patterns require consideration.In particular, these values can be used when determining air-condi-tioning loads during periods of maximum solar radiation. The val-
32、ues listed in the tables include Dry-bulb temperature corresponding to 0.4, 2.0, 5.0, and 10.0%cumulative frequency of occurrence for indicated month, F; meancoincident wet-bulb temperature, F. Wet-bulb temperature corresponding to 0.4, 2.0, 5.0, and 10.0%cumulative frequency of occurrence for indic
33、ated month, F; meancoincident dry-bulb temperature, F.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 record. Monthly percentile values of dry-
34、or wet-bulb tempera-ture may be higher or lower than the annual design conditions cor-responding to the same nominal percentile, depending on the monthand the seasonal distribution of the parameter at that location. Gen-erally, for the hottest or most humid months of the year, the monthlypercentile
35、value exceeds the design condition for the same elementTable 1A Nomenclature for Tables of Climatic Design ConditionsCDDn Cooling degree-days base nF, F-dayCDHn Cooling degree-hours base nF, F-hourDB Dry-bulb temperature, FDP Dew-point temperature, FEbn,noon Clear sky beam normal irradiances at sola
36、r noon, Btu/hft2Edh,noon Clear sky diffuse horizontal irradiance at solar noon, Btu/hft2Elev Elevation, ftEnth Enthalpy, Btu/lbHDDn Heating degree-days base nF, F-dayHours 8/4 90 = East)Period Years used to calculate the design conditionsPrecAvg Average precipitation, in.PrecSD Standard deviation of
37、 precipitation, in.PrecMin Minimum precipitation, in.PrecMax Maximum precipitation, in.Sd Standard deviation of daily average temperature, FStdP Standard pressure at station elevation, psitaub Clear sky optical depth for beam irradiancetaud Clear sky optical depth for diffuse irradianceTavg Average
38、temperature, FTime Zone Hours ahead or behind UTC, and time zone codeWB Wet bulb temperature, FWBAN Weather Bureau Army Navy numberWMO# Station identifier from the World Meteorological OrganizationWS Wind speed, mphNote: Numbers (1) to (41) and letters (a) to (p) are row and column referencesto quic
39、kly point to an element in the table. For example, the 5% design wet-bulb temperature for July can be found in row (29), column (k).14.4 2013 ASHRAE HandbookFundamentalscorresponding to the same nominal percentile. For example, Table 1shows that the annual 0.4% design dry-bulb temperature at Atlanta
40、,GA, is 93.9F; the 0.4% monthly dry-bulb temperature exceeds93.9F for June, July, and August, with values of 94.5, 97.8, and97.4F, respectively. Fifth and tenth percentiles are also provided togive a greater range in the frequency of occurrence, in particularproviding less extreme options to select
41、for design calculations.A general, very approximate rule of thumb is that 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
42、temperature for the hottest month; the 1%annual value is roughly equivalent 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
43、-bulb temperature profiles, as ex-plained in the section on Generating Design-Day Data. Three kindsof profile are defined: Mean daily temperature range for month indicated, F (defined asmean of difference between daily maximum and minimum dry-bulb temperatures). Mean daily dry- and wet-bulb temperat
44、ure ranges coincident withthe 5% monthly design dry-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 dry-bulb temperature exceeds the 5% monthly designdry-bulb temperature. Mean dai
45、ly dry- and wet-bulb temperature ranges coincident withthe 5% monthly design 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 designw
46、et-bulb temperature.Clear-Sky Solar Irradiance. Clear-sky irradiance parametersare 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 calculat
47、ions because June 21 and December 21 represent thesolstices (longest and shortest days) and March 21 and September21 are close to the equinox (days and nights have the same length).Parameters listed in the tables are Clear-sky optical depths for beam and diffuse irradiances, whichare used to calcula
48、te beam and diffuse irradiance as explained inthe section on Calculating Clear-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.Data SourcesThe followi
49、ng two primary sources of observational data setswere used in calculating design values: Integrated Surface Dataset (ISD) data for stations from around theworld provided by NCDC for the period 1986 to 2010 (Lott et al.2001; NCDC 2003). Hourly weather records for the period 1986 to 2010 for 559 Cana-dian locations from Environment Canada (2013).In most cases, the period of record used in the calculationsspanned 25 years. This choice of period is a compromise betweentrying to derive design conditions
