建筑環(huán)境學chapter4.1-2 thermal comfortable (11)

1、7 Artificial Lighting 人工照明人工照明 pThe subject of this chapter is artificial lighting, and p本章的主題是人工照明 p the following chapter deals with natural lighting. p下一章會講自然采光 pAlthough the principles of these two topics are treated separately 盡管分開講解著兩部分內容 pit is important that they are considered together when

2、 designing a building.但在創(chuàng)造建筑光環(huán)境時兩者都要考慮 The main functions of artificial lighting? 人工照明的主要功能人工照明的主要功能 lto provide enough light for people to carry out a particular activity l為人們進行某一活動提供足夠的光 lto provide enough light for people to move about with ease and safety l為人們方便行走和人身安全提供足夠的光 to display the featu

3、res of the building in a manner suitable for its character and purpose 更好的表現(xiàn)建筑特點和用途 lTo achieve these aims it is necessary to consider the properties of lamps, of the lamp fittings 燈具and of the room surfaces that surround them. l要達到上述目的，就需要考慮燈、燈具及室內表面的特性 lWhat is The oldest source of artificial ligh

4、t ? the flame from fires, from candles and from oil lamps lConvert chemical combustion化學燃燒 to light energy lModern sources of artificial light convert electrical energy to light energy lproduce light by heating substances to a temperature at which they glow發(fā)熱and are luminous. lthe electrodes 電極+ ion

5、ized gas電離氣體 +electric current 電流 lTypically, such lamps use a noble gas (argon, neon, krypton and xenon) or a mixture of these gases. 惰性氣體（氬、氖、氪 、氙 ） lresulting in visible light or ultraviolet radiation lUltraviolet radiation is converted to visible light by a fluorescent coating inputpower Electri

6、cal outputflux Luminous efficacy luminous Unit: lumens /watt (lm/W) lThe luminous efficacy of a lamp decreases with time 燈的光效隨著使用時間降低 l for a discharge lamp it may fall by as much as 50% before the lamp fails. 對氣體放電燈，在失效前光效會下降50% lThe nominal life of a lamp is usually determined by the manufacturer

7、by considering the failure rate of a particular model of lamp combined with its fall in light output. 燈的壽命一般由廠家考慮某批燈的失效率結合光效降低程度而定 lIn a large installation it is desirable that all the lamps are replaced at the same time on a specified maintenance schedule. 在安裝大量燈的情況下，在維護計劃中，燈要求同時更換掉。 is the absolut

8、e temperature of a perfect radiator when the colour apperance of the radiator best matches that of the light source Unit : kelvin (K) The CCT reflects the apparent color of light itself, lThe lower values of colour temperature indicate light with a higher red content. l光源色溫為6900K表示（ ） lA 光效很高 lB 光效很

9、低 lC 光色偏冷色 lD 光色偏暖色 lSome examples of colour temperatures are given below is the ability of a light source to reveal the colour appearance of surfaces. lreference source such as daylight lcolour rendering index（Ra) which has a value of 100 for an ideal lamp. lPractical sources of white light range i

10、n Ra value between 50and 90 顯色性是指燈光對其照射的物體的影響作用。顯色性是指燈光對其照射的物體的影響作用。 The CIE colour rendering groups Group Ra Importance Typical application 1A 90. 100 accurate colour matching Galleries畫廊，美術館, medical examinations, colour mixing 1B 80. 90 accurate colour judgement Home, hotels, offices, schools 2 6

11、0. 80 moderate colour rendering Industry, offices, schools 3 40. 60 accurate colour rendering is of little importance Industry, sports halls 4 20. 40 accurate colour rendering is of no importance Traffic lighting Colour rendering index for different light sources Light sourceColour rendering group I

12、ncandescent 白熾燈 1A Metal halide 金屬鹵燈1A . 2 Fluorescent 熒光燈1A . 3 High pressure sodium 高壓鈉燈1B . 4 Low pressure sodium 低壓鈉燈4 The lower values of colour temperature indicate light with a higher red content. passing an electric current through a filament of metal and raising the temperature to white hea

13、t. When the metal is incandescent熾熱的, at around 2800K , useful quantities of light are given off. common light bulb 普通燈泡普通燈泡 be clear or frosted透明的或磨砂的. contains either a vacuum or an inert gas to prevent oxidation of the hot filament. The cost is low 費用低 its installation is simple 安裝簡單 relatively s

14、hort life 壽命短 1000h the labour costs of replacement to be high更換所需人工費高 The low luminous efficacy 光效低 12-18.6 lm/w high electrical running costs 費電 lOnly about 5% of the electrical energy visible light lmost of the energy consumed is given off as heat, especially radiant heat. Characters of a tungste

15、n filament lamp 鎢絲燈的特點鎢絲燈的特點 a) Spot lamps : glass bulb silvered inside and shaped to form a parabola with the filament at the focus. b) Sealed beam lamps use similar techniques C) Crown-silvered lamps are standard filament lamps where the glass bulb is silvered in front. gives narrow beams of light

16、 lHalogen 鹵素 lA small quantity of a halogen gas, e.g. iodine 碘 or bromine溴 lrun at higher temperatures This gives it a higher efficacy (1030 lm/W). 1500h luses 12volt llow-voltage bulbs need a lower resistance lfilament can be shorter, thicker and stronger. lgood directional qualities lpopular in sh

17、ops for the display of goods. lThe relatively low heat output lcan not cause overheating. Figure 7.2 Tubular fluorescent lamp McMullan 氬或氪氬或氪 lThe cost is high lHigh luminous efficacy 45 lm/w lRelatively long life 1500-5000h 10000h above aboard lApart from the well-known tubular fluorescent lamp, us

18、ually have a poor colour rendering been restricted to outdoor lighting Characters of gas discharge lamps 氣體放電燈的特點氣體放電燈的特點 Modern types of discharge lamp 現(xiàn)代的氣體放電燈現(xiàn)代的氣體放電燈 lcolour rendering good enough for large-scale interior lighting 顯色性能大大提高，可廣泛用于室內大面積照明顯色性能大大提高，可廣泛用于室內大面積照明 lsuch as factories and

19、warehouses. 比如工廠和倉庫比如工廠和倉庫 lhigh efficiency give significant energy savings in buildings 高光效能顯著節(jié)能高光效能顯著節(jié)能 lMany CFLs are designed to replace an incandescent lamp llow-energy 低能耗低能耗 A tubular-type 管式管式 most popular types in Europe. A spiral-type螺旋式螺旋式 slightly reduced efficiency Characters of CFLs 緊湊

20、型熒光燈的特點緊湊型熒光燈的特點 lCFLs use less power 用電少用電少 lhave a longer life 壽命長壽命長 lIn the United States, a CFL has a higher purchase price than an incandescent lamp, but can save over US$40 in electricity costs over the lamps life time. 在美國，該燈的價格要高于白熾燈，但整個壽命內可節(jié)約在美國，該燈的價格要高于白熾燈，但整個壽命內可節(jié)約 的電費達的電費達40美元美元 lLike a

21、ll fluorescent lamps, CFLs contain mercury, which complicates their disposal 和其他熒光燈一樣，和其他熒光燈一樣，CFLs含有汞蒸氣，處理起來復雜含有汞蒸氣，處理起來復雜 luses mercury in an excited state激發(fā)狀態(tài)激發(fā)狀態(tài) to produce light. lmercury lamp emits sharp light at certain blue and green wavelengths. 發(fā)藍、綠光發(fā)藍、綠光 lmercury halide lamp鹵汞燈鹵汞燈, better

22、 colour rendering high efficacy A metal halide gas discharge lighting system provides illumination for a college baseball game at Olsen Field in College Station, Texas. Note the various colors of the lights as they warm up Low-pressure sodium lamps 低壓鈉燈低壓鈉燈 Sodium 鈉（發(fā)光）鈉（發(fā)光） Mercury 汞（緩沖劑和增加放電電抗的作用）

23、汞（緩沖劑和增加放電電抗的作用） xenon 氙氣氙氣 （起?。ㄆ鸹。?distinctive 鮮明的yellow light gives poor colour rendering . Very high efficacy been traditionally used for street lighting 燈塔指示燈、航道、機場跑道的照明燈塔指示燈、航道、機場跑道的照明 High-pressure sodium lamps （SON）高壓鈉燈）高壓鈉燈 produce a continuous spectrum without much blue light a colour rend

24、ering more acceptable used in modern street lighting and for the economic lighting of large areas such as forecourts籃球場籃球場 and warehouses倉庫倉庫. Office building illuminated by high pressure sodium lamps. 無極燈無極燈 l高頂棚工業(yè)廠房的照明光源應選用 l高顯色光源 l高光效光源 l瞬間啟動光源 l低色溫光源 langle in (incidence) equals angle out (refle

25、ction) langles measured from surface “normal” (perpendicular) surface normal same angle incident ray exit ray reflected ray Virtual Images in Plane Mirrors If light energy doesnt flow from the image, the image is virtual. Rays seem to come from behind the mirror, but, of course, they dont. It is vir

26、tually as if the rays were coming from behind the mirror. Virtually: the same as if As far as the eye-brain system is concerned, the effect is the same as would occur if the mirror were absent and the chess piece were actually located at the spot labeled virtual image. l低色溫的 光源是（ ） l表面溫度高 l光色偏青白 l光色

27、偏橙黃 l光效較高 l下列光源顯色指數高的光源是（ ） l氖燈 l紫燈、 l日光燈 l高壓汞燈 “image” you “real” you mirror only needs to be half as high as you are tall. Your image will be twice as far from you as the mirror. Forming Images with a Plane Mirror A mirror is an object that reflects light. A plane mirror is simply a flat mirror. C

28、onsider an object placed at point P in front of a plane mirror. An image will be formed at point P behind the mirror. dodi For a plane mirror: do = -di and ho = hi ho hi do = distance from object to mirror di = distance from image to mirror ho = height of object hi = height of image Image is behind

29、mirror: di 0 Illusions, Mirages lLighting is an important area of energy conservation in buildings la shorter payback period light fixture or light fitting lamp(s) its ofoutput light luminaire ofoutput light downwards DLOR lamp(s) its ofoutput light luminaire ofoutput light upwards ULOR lamp(s) its

30、ofoutput light luminaire ofoutput light Total LOR ULORDLORLOR Lets do some judgements Direct 直接向下型直接向下型 51 General diffusing 普通漫反射型普通漫反射型 Semi-indirect 半間接型半間接型 燈具的配光曲線燈具的配光曲線 l任何光源或燈具一旦處于工作狀態(tài)，就必須向四周空間投任何光源或燈具一旦處于工作狀態(tài)，就必須向四周空間投 射光通量。我們把燈具各方向的發(fā)光強度在三維空間里用射光通量。我們把燈具各方向的發(fā)光強度在三維空間里用 矢量表示出來，把矢量的終端連接起來，則構成

31、一封閉的矢量表示出來，把矢量的終端連接起來，則構成一封閉的 光強體。當光強體被通過光強體。當光強體被通過z z軸的平面截割時，在平面上獲軸的平面截割時，在平面上獲 得一封閉的交線。此交線以極坐標的形式繪制在平面圖上，得一封閉的交線。此交線以極坐標的形式繪制在平面圖上， 這就是燈具的配光曲線。這就是燈具的配光曲線。 l配光曲線上的每一點，表示燈具在該方向上的發(fā)光強度。配光曲線上的每一點，表示燈具在該方向上的發(fā)光強度。 l知道燈具對計算點的投光角知道燈具對計算點的投光角 ，就查到相應的發(fā)光強度，就查到相應的發(fā)光強度， 利用照度余弦定律，就可求出點光源在計算點形成的照度。利用照度余弦定律，就可求出點

32、光源在計算點形成的照度。 燈具效率燈具效率 l任何材料制成的燈罩，對于投射在其表面的光通量都要被任何材料制成的燈罩，對于投射在其表面的光通量都要被 它吸收一部分，光源本身也要吸收少量的反射光，余下的它吸收一部分，光源本身也要吸收少量的反射光，余下的 才是燈具向周圍空間投射的光通量才是燈具向周圍空間投射的光通量 l在規(guī)定條件下測得的燈具發(fā)射光通量與燈具內的全部光源在規(guī)定條件下測得的燈具發(fā)射光通量與燈具內的全部光源 在燈具外按規(guī)定條件測得的光通量之比在燈具外按規(guī)定條件測得的光通量之比 First , find the standard service illuminance levels 照度標準

33、照度標準 Table 7.3. P156 for different applications The aim of Lighting design is to reach the illuminance levels Then , choose the luminaires 選擇燈具 use Lumen method 流明法流明法 to calculate the number of lamps needed. LLFUFF AE N DLOR )WL(H WL RI m Hmmounted height of the luminaire above the working plane LL

34、FUFF AE N UF= utilisation factor is the ratio of the total flux reaching the working plane compared to the total flux output of the lamps 光源實際投射到工作面上的有效光通量與全部燈的額定光通量之比 LLF=light loss factor is the ratio of the illuminance provided at some given time compared to the initial illuminance At the end of

35、design, we should place these lamps in a regular grid pattern and . type of luminaire + height at which they set. Typical values are as follows Smax=1.5XHm Smax=1.0XHm Figure 7.6 spacing of luminaires P160 A factory space in height requires a service illuminance of 500lux on the work benches which a

36、re set 1m above the floor. The 65W tubular fluorescent lamps chosen have a luminous efficacy of 80lm/W. they are to be mounted on the ceiling in luminaires which have a DLOR of 50%. The room reflectances are 0.5 for the ceiling and 0.3 for the wall; the initial light loss factor is 0.7 a) Use the lu

37、men method of design to calculate the number of lamps required b) Suggest a suitable layout for the lamp fittings. lE=? lA=? lF=? lUF=? lLLF=? LLFUFF AE N So number of lamps required=144 lamps Suggested layout: Check spacing using Smax=1.5XHm =1.5X3=4.5m So the suggested layout is satisfactory provided that the distance between lamps is not greater than 4.5m lLight quantity should reach the illuminance levels Natural light 自然光自然光 61 lColour quality 光的顏色光的顏色 Glare 眩光眩光 lDirectional quality 方向性 lEnergy use 能耗 lCosts 運行費 lPhysic