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1、<p><b>  外文資料及譯文</b></p><p>  The Control Methods for Radiant Floor Heating</p><p>  in High-Rise Residential Building</p><p><b>  Abstract </b></p&g

2、t;<p>  High-rise residential building should cope with the fluctuating thermal load by accurate control because the thermal load of each zone varies so widely with the time.In order to find the accurate control m

3、ethod for the building, this study classified the current control methods into supply water temperature control, supply water flow rate control and supply water temperature plus flow rate control. </p><p>  

4、And the comparative experiments on control methods were conducted in a test cell and the control performances were evaluated by analyzing room air temperature, surface temperature and rising time of room temperature.<

5、/p><p>  The fluctuation of the room air temperature is reduced when the outdoor reset control is used with on/off control. The rising time of room air temperature is the shortest when on/off pulse width modula

6、tion control is applied during the heating start-up period. </p><p>  keywords: radiant floor heating, control method, high rise residential building</p><p>  1. Introduction </p><p&g

7、t;  In korea, many high-rise buildings are constructed in these days due to the rapid economic development and the high population densities.And as the living standards are becoming more and more improved, the request fo

8、r indoor environmental quality has become key issues for both the residents and estate developers.</p><p>  However, the building is exposed to the severe outdoor condition since the wind speed and solar rad

9、iation increase as the building grows higher and the outdoor conditions in the upper atmosphere are more severe than those observed at the ground level.</p><p>  For this reason, heating load is bound to flu

10、ctuate and increase severely in winter. So this difference cannot be ignored for heating system design and indoor comfort (kumar 1997). </p><p>  Furthermore, high-rise building generally gets rid of the bal

11、cony to enlarge the available floor area, and comprises a central core and housing units to have more external walls and windows for daylight and ventilation. Consequently, the room air temperature and the heating load o

12、f the building fluctuate transiently in winter due to the absence of buffer space. In korea, radiant floor heating system is generally adopted in residential building (kim 2003) with the simple on/off control method</

13、p><p>  If the simple control is applied to the high-rise building, the control system could not respond the change of the heating load and cause the over-heating or under-heating conditions. Inorder to achieve

14、 the comfort and energy saving inhigh-rise residential building, it is required to search for the accurate control method that is suitable to the characteristics of high-rise residential building. </p><p>  

15、In this study, the heating load of high-rise residential building was analyzed and compared with that of low-rise residential building by transient simulation. And the control methods that can provide accurate control fo

16、r radiant heating system were studied through the experiments. The control methods were compared with one another from the view point of the stability of room air temperature, floor surface temperature and the rising tim

17、e of room air temperature during the start-up time.</p><p>  2. The Heating Load Analysis </p><p>  2.1 Characteristics of high-rise residential building </p><p>  In high-rise resi

18、dential building, air tight curtain wall system is adopted to prevent excessive infiltration and the depth of the slab decreases to lighten the structure of the building. So heat storage capacity of the structure can be

19、lowered. As shown in Fig.1, compared with low-rise residential building, high-rise residential building has no balcony that functions as a shading device or thermal buffer, and comprises a central core and residential un

20、its extending outward from the core in seve</p><p>  Also, although facing south has been the favorable building orientation to provide an exterior view and solar right to the occupants in low-rise residenti

21、al building, eastern and western envelope is typically designed with double glazing windows in high-rise residential building. Because of this envelope design, the heat loss can be increased more severely as compared wit

22、h the low-rise residential building. </p><p>  Moreover, as there are no adjacent tall buildings, its envelope is not influenced by the shade of adjacent buildings. Consequently, the building is influenced s

23、o directly by the outdoor temperature and solar radiation that the heating load of each zone varies widely with the time (Athienist 2003)</p><p>  2.2 The heating load simulation </p><p>  To an

24、alyze the thermal characteristic of high-rise residential building, a simulation comparing low- and high-rise residential building was performed. A transient simulation program (TRNSYS), which is able to evaluate the eff

25、ect of the thermal mass and solar radiation on the multi-zone building, was used in the simulation.</p><p>  Fig.1. (a) shows the plan of a low-rise residential building which was analyzed in the simulation.

26、 It is a typical apartment building which is composed of one living room (LV) and four bed rooms (R1~R4). Each room has a balcony that is 1.2m ~ 1.5m in width. Fig.1. (b) shows the plan of a high-rise residential buildin

27、g of which heating load was simulated and evaluated. Four rooms (LV, R1~R3) face the outdoor air without a balcony and one room (R4) is surrounded by adjacent rooms or corridors.</p><p>  The simulation was

28、performed during the winter season (October 1 ~ March 31) using standard meteorological data of Seoul, provided by SAREk(Society of Air-conditioning and Refrigeration of korea).</p><p>  Design temperature a

29、nd relative humidity was 20ºC and 40% respectively. And the infiltration through the envelope was 1.0 ACH for low-rise building and 0.3 ACH for high rise building (Ahn1999). The effect by internal heat gain was not

30、taken into account. </p><p>  2.3 Simulation results and discussion </p><p>  2.3.1 Simulation results </p><p>  Fig.2. (a) describes the heating load variation on the day when h

31、eating load is the highest in the year. The maximum heating load is 45W/㎡. And the heating load of each zone varies smoothly with the time and shows the similar pattern, that is, inversely proportional to the outdoor tem

32、perature. It can be induced that the heating load is determined mainly by the outdoor temperature because a balcony reduces the effect by solar radiation. </p><p>  To find the influence of a balcony on the

33、heating load, the case that the floor was extended into existing balcony was simulated. As shown in Fig.2. (b), the heating load records maximum value of about 60W/㎡ and fluctuates wider than the previous case. In partic

34、ular, the heating load of the rooms facing the south (LV, R1, R4) drops and rises profoundly as the solar radiation varies with the time. It can be thought that the removal of balconies increases the effect by the solar

35、radiation on the t</p><p>  Fig.3. plots the heating load variation of high-rise residential building. The heating load goes through the excessive fluctuation as time goes by. The heating load of each zone,

36、except for R4, plummets as the sun rises and solar radiation increases. R1, facing the south, has little heating load during daytime owing to the solar radiation, which hints that cooling load can be generated if the i

37、nternal heat gain increases or the weather gets somewhat mild.</p><p>  The heating load of R2 and R3, facing the east, bounces up at 10 a.m. as the sun moves to the south. And from 12 a.m. on, the heating l

38、oad shows the tendency to vary as the outdoor temperature changes. In case of R4, the fluctuation is very slight because it does not receive the effect of the outdoor climate directly. </p><p>  2.3.2 Disc

39、ussion </p><p>  The heating load of low-rise residential building is kept so relatively stable that the control does not need to respond to the abrupt change of the thermal load. But in case of no balcony,

40、it is desirable that the fluctuation of heating load should be compensated by the more accurate control method. </p><p>  3. Comparison of Control Methods </p><p>  An effective control system n

41、eeds to supply heat at the same rate, at which the building loses heat under dynamic conditions, and maintain stable and comfortable indoor temperature. To achieve this goal, a number of control methods for the radiant f

42、loor heating system have been suggested and applied by many researchers (MacCluer 1989, Leigh 1992, Gibbs 1994, Cho 1999, Rekstad 2003). </p><p>  To control the radiant floor heating system accurately on th

43、e basis of these control methods, it is necessary to categorize various control methods and to do a comparative study of each control method through experiments in the laboratory. In this study, existing control methods

44、that have been suggested or applied were firstly classified by control parameters and experimented on each control method.</p><p>  3.1 Control parameters and control methods </p><p>  3.1.1 Con

45、trol parameters </p><p>  Control parameters for the radiant floor heating system can be classified into input variables controlled variables and manipulated variables, as shown in Table 1. Input variables a

46、re measured values that give a feedback to a control system so that a controller might make output values. Controlled variables act as a set point that is necessary to keep controlled space comfortable. Manipulated varia

47、bles are the objects that can be handled so that controlled variables might satisfy the set point. </p><p>  3.1.2 Classification of control methods </p><p>  As previously mentioned, the contro

48、l methods for the radiant floor heating system can be classified into the combination of supply water temperature control, supply water flow rate control and flux modulation according to the manipulated variables, as sho

49、wn in Table 2. </p><p>  The supply water temperature control method can be classified into outdoor reset control, which controls the supply water temperature by sensing the outdoor temperature, and outdoor

50、 reset with indoor temperature feedback control, which controls the supply water temperature by sensing both the outdoor temperature and the room air temperature (Adlam 1949). Due to the dominant impact of the outdoor te

51、mperature on the space heating load, it is desirable for the supply water temperature to be control</p><p>  In order to control the flow rate of supply water, there are two types of control methods that can

52、 be used - the continuous flow rate control and the intermittent flow rate control. A continuous flow rate has a variable flow control, and an intermittent flow rate has on/off bang-bang control and on/off pulse-width mo

53、dulation (PWM) (Tekmar 1996). </p><p>  3.2 Experiments for comparison of control methods</p><p>  Based on the above classification of control methods as in Table 2, the experiments that compar

54、e three kinds of control methods (water temperature control methods, flow rate control methods and water temperature plus flow rate control methods) were conducted in a laboratory. The experiments cases are described in

55、Fig.6. </p><p>  Because it is a purpose to find an accurate control method that can provide a stable environment with high rise residential building, control methods were compared with one another from the

56、viewpoint of the stability of room air temperature, floor surface temperature, and the rising time of room air temperature. </p><p>  4. Conclusions </p><p>  This study compared the heating l

57、oad characteristic of low rise with high rise residential building and found that the heating load of high rise residential building was influenced directly by outdoor condition. And it was pointed out that the control m

58、ethods of radiant floor heating system for high rise residential building should be more accurate. To find out the accurate control methods for high rise residential building, experiments to compare the performance of

59、each control method were co</p><p>  (1) In order to keep the room air and floor surface temperature stable, it is more advantageous to apply the water temperature control method rather than the water flow r

60、ate control method.</p><p>  (2) It is recommendable to use outdoor reset control in combination with simple on/off bang-bang control to reduce the fluctuation of room air temperature. </p><p>

61、;  (3) In case of applying water temperature control or water temperature plus flow control, it is necessary to equip setback devices due to prolonged rising time during the heating start-up time. </p><p> 

62、 (4) With regard to the high-rise residential building serviced by district heating, it is more advantageous to apply outdoor reset plus PWM control than outdoor reset plus on/off control in terms of the stability of roo

63、m temperature and energy saving. </p><p><b>  譯 文</b></p><p>  高層住宅大廈中地板輻射采暖的控制方法</p><p><b>  摘要 :</b></p><p>  高層住宅建筑應(yīng)該對熱負荷的波動進行精確控制,因為每個區(qū)域在不同

64、的時間內(nèi)熱負荷不同。為了找到精確精確的控制方法,這項研究分為,直接控制供水溫度,供水流量和溫度同時控制。通過分析室內(nèi)溫度,地表溫度和室內(nèi)溫度上升的情況對研究控制方法的實驗進行了測試和控制性能的評價。當戶外復(fù)位控制開關(guān)使用時,室內(nèi)溫度的波動減小。當開關(guān)調(diào)在暖氣啟動階段時,室內(nèi)溫度將在最短的時間內(nèi)上升。</p><p>  關(guān)鍵詞:地板輻射采暖,控制方法,高層住宅樓</p><p><b

65、>  1.簡介</b></p><p>  在韓國,由于經(jīng)濟的快速發(fā)展和熱口密度增高,許多高層建筑應(yīng)運而生。隨著人們生活水平的提高,室內(nèi)環(huán)境質(zhì)量問題已成為居民和房地產(chǎn)開發(fā)商考慮的關(guān)鍵問題。然而,建筑面臨的嚴峻狀況是由于越來越高的建筑和室外條件下高層大氣的影響,使得室外風(fēng)速增大,太陽輻射增加。這樣以來,熱負荷必然出現(xiàn)波動,并且在冬季更為嚴重。因此,在供暖系統(tǒng)和室內(nèi)舒適設(shè)計中,這種差異是不容忽視的。

66、</p><p>  此外,高層建筑通過陽臺擴大現(xiàn)有建筑面積,這樣以來就有了更多哦的外部墻壁、太陽輻射和室外通風(fēng)。因此,室內(nèi)空氣溫度和熱負荷波動在冬季變化非常嚴重。在韓國,地板輻射采暖一般通過簡單的開關(guān)控制。但是在高層建筑使用簡單的開關(guān)控制,控制系統(tǒng)可能由于過度加熱或者在過熱條件下不能完成熱負荷變化的響應(yīng),所以在高層住宅大廈中實現(xiàn)舒適性和節(jié)能要求,還需要尋求精確的控制方法來適用于有特設(shè)要求的高層住宅樓。</

67、p><p>  在這項研究中,通過模擬分析和比較高層住宅建筑和低層住宅建筑的熱負荷。通過這個實驗的控制方法可以通過精確的控制地板輻射采暖暖系統(tǒng),這個控制方法是比較在啟動加熱系統(tǒng)時,室內(nèi)溫度,地板表面溫度和上升時間的關(guān)系。</p><p><b>  2. 熱負荷分析</b></p><p>  2.1 高層住宅樓的特性</p><

68、;p>  在高層住宅樓,空氣填充墻是通過防止?jié)B透和深入的板坯來減少減輕的建筑,因此,徐熱能力比較低,圖1所示,與底層住宅相比,高層住宅樓沒有陽臺充當著因設(shè)備或熱緩沖區(qū),并通過住宅向外延伸的更多的外部墻壁和窗戶來獲得更多的光線和通風(fēng)。</p><p>  此外,雖然在低層住宅建筑中,面朝南被認為是最好的建筑方向,提供一個充分利用太陽能的特點,但在高層住宅樓中,東面和西面通常有采用雙層玻璃墻設(shè)計的窗戶。因為這個

69、窗戶的設(shè)計,使得熱損失與底層建筑相比可提高不少。</p><p>  此外,由于沒有相鄰的高樓大廈,其設(shè)計不影響其遮蔭下臨近建筑物,因此,在各個時間段內(nèi)該建筑直接影響室外溫度和太陽輻射的每個區(qū)域。</p><p><b>  2.2熱負荷模擬</b></p><p>  分析了高層住宅樓的特性,模擬了低層和高層住宅樓的比較。瞬態(tài)仿真程序(TRN

70、SYS),通過它可以用來模擬不同區(qū)域里建筑物熱負荷和太陽輻射的影響,并能夠進行比較客觀的評價,圖1 。(一)表明該程序?qū)Φ蛯幼≌M行分析的仿真。這是一個由一個客廳和4個房間組成的典型的公寓樓。每個房間都有1.2~1.5米的陽臺圖1。(二)表明該程序?qū)δ掣邔幼≌ㄖ臒嶝摵蛇M行了模擬和評價。 4個房間(LV, R1~R3)面對室外空氣沒有陽臺和一個房間( R4 )的四周鄰近房間或走廊。進行冬季( 10月1日?~3月31日)仿真,使用由韓國

71、SAREk (學(xué)會空調(diào)制冷韓國)提供的標準的氣象數(shù)據(jù),設(shè)計溫度和相對濕度是20℃和40 % 。滲透墻體為1.0的ACH的低層樓房和0.3的ACH的高層建筑( Ahn1999 )沒有考慮影響內(nèi)部熱增益。</p><p>  2.3仿真結(jié)果和討論</p><p><b>  2.3.1仿真結(jié)果</b></p><p>  圖2 。(一)介紹了一年中

72、熱負荷最高的那天的熱負荷變化。最大熱負荷為45W / ㎡ 。每一區(qū)的熱負荷,跟隨著不同的時間的變化顯示了類似的模式,也就是與室外溫度成反比。因為陽臺減少了太陽輻射的效果,可以誘導(dǎo)熱負荷變化的主要因素是室外溫度。</p><p>  要查找陽臺對熱負荷的影響,請延長到現(xiàn)有的陽臺進行模擬。圖2 ( b )項,熱負荷記錄最高價值約60W/ ㎡和波動比以往更廣泛。特別是,房間面臨南(LV, R1, R4)的太陽輻射下降和

73、上升隨時間的變化??梢哉J為,陽臺的影響可以增加太陽輻射的熱環(huán)境。</p><p>  圖3 .小區(qū)高層住宅樓熱負荷的變化。熱負荷經(jīng)過過度波動隨著時間的推移。熱負荷的每一區(qū),除R4 ,直線下降的太陽升起和太陽輻射增加。R1 ,面向南方,白天太陽輻射幾乎沒有熱負荷,這表示,如果內(nèi)部收益增加或天氣有點輕微變化,冷負荷可以產(chǎn)生熱量。R2和R3的熱負荷,面向東,過了上午10時太陽移到南方。從12時,熱負荷的趨勢表明室外溫度

74、變化時,R4的波動是非常輕微的,因為它沒有受到室外氣候直接影響。</p><p><b>  2.3.2討論</b></p><p>  低層住宅的熱負荷控制不需要應(yīng)對突然變化的熱負荷就可以保持相對穩(wěn)定。但是,如果沒有陽臺,可取的做法就是通過更精確的控制方法來補償熱負荷的波動。</p><p><b>  3.控制方法的比較</

75、b></p><p>  有效的控制系統(tǒng)供熱要求以同樣的速度,在動力條件下使建筑失去熱量,并保持穩(wěn)定和舒適的室內(nèi)溫度。為了實現(xiàn)這一目標,許多研究人員提出并實施了一些地板輻射采暖控制方法,如(MacCluer 1989, Leigh 1992, Gibbs 1994, Cho 1999, Rekstad 2003)</p><p>  對這些控制地板輻射采暖系統(tǒng)的方法,有必要在實驗室下

76、對每個方法進行分析比較研究后進行分類。在這項研究中,對每個現(xiàn)有的控制方法,已經(jīng)提出或?qū)嵤┝说谝粴w類試驗控制參數(shù)和控制方法。</p><p>  3.1 控制參數(shù)和控制方法</p><p>  3.1.1 控制參數(shù)</p><p>  地板輻射采暖系統(tǒng)的控制采納數(shù)可分為輸入變量、控制變量、操縱變量,如表1所示,輸入變量的測量值。傳輸?shù)娇刂葡到y(tǒng),使控制器輸出值,控制變量

77、作出反應(yīng),判斷是否控制空間舒適,操縱變量的對象可以處理,以便控制變量滿足設(shè)定值。</p><p>  3.1.2 分類控制方法</p><p>  如前所述,地板輻射采暖系統(tǒng)控制方法可分為供水溫度控制,供水流量控制和根據(jù)操縱變量調(diào)制流量。如表2所示。</p><p>  供水溫度的控制方法可分為室外復(fù)位控制,控制供水溫度感應(yīng)室外溫度,室外與室內(nèi)溫度重置反饋控制,控制

78、供水溫度傳感的室外溫度和房間空氣溫度( Adlam 1949)。由于室外溫度的空間熱負荷占主導(dǎo)地位的影響,這是可根據(jù)不同的室外溫度決定供水溫度。</p><p>  為了控制流量供水,有兩種類型的控制方法,可用于持續(xù)流量控制和間歇流量控制。連續(xù)流動速度有變流量控制,并有間歇性流量開/關(guān)Bang - Bang控制和開/關(guān)的脈沖寬度調(diào)節(jié)( PWM ) ( Tekmar 1996) 。</p><p

79、>  3.2控制方法實驗的比較</p><p>  根據(jù)上述分類的控制方法,如表2,試驗,比較三種控制方法(水溫度的控制方法、流量控制方法、水溫以及流量控制方法)進行實驗,圖6描述實驗的流程. 因為它的目的是找到一個準確的控制方法,可以提供一個穩(wěn)定的高層住宅環(huán)境,控制方法對彼此的觀點的穩(wěn)定,室內(nèi)空氣溫度,地面溫度和時間的增加房間空氣溫度進行了比較。</p><p><b>

80、  4.結(jié)論</b></p><p>  這項研究比較了底層與高層熱負荷特點,發(fā)現(xiàn)直接影響高層住宅熱負荷的是戶外條件。并指出,該地板采暖系統(tǒng)控制方法在高層住宅樓應(yīng)用應(yīng)該更加準確。找出共層住宅樓精確控制方法,實驗對每個控制方法進行了比較。這項研究的結(jié)果可以歸納如下:</p><p>  (1)為了保持室內(nèi)空氣和地板表面溫度的穩(wěn)定,更有利的是水溫控制方法,而不是水流量控制方法。 &

81、lt;/p><p>  (2)推薦使用室外復(fù)位控制,結(jié)合簡單的開/關(guān)Bang - Bang控制,以減少房間空氣溫度的波動。</p><p>  (3)在水溫控制或水溫加流量控制情況下,由于在供暖啟動期溫度的持續(xù)上升時間過長,有必要增加輔助設(shè)備。 </p><p>  (4)考慮到高層住宅的分區(qū)供熱,在穩(wěn)定的室溫和節(jié)能條件下,使用戶外復(fù)位開關(guān)和PWM評價控制比室外開/關(guān)控

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