一、屋頂通風器的工作原理
屋頂通風器是依靠自然(ran)風(feng)壓和熱(re)(re)壓實現室內外空(kong)氣(qi)的(de)(de)流動與置換(huan),從而達(da)到改善空(kong)氣(qi)質(zhi)量的(de)(de)目的(de)(de)。風(feng)壓和熱(re)(re)壓是屋頂通風(feng)器(qi)最基(ji)本的(de)(de)動力。
1、風壓作用下的自然通風
當風(feng)吹向建(jian)筑(zhu)(zhu)物(wu)(wu)時(shi),建(jian)筑(zhu)(zhu)物(wu)(wu)對風(feng)有(you)阻擋作用,在迎(ying)(ying)風(feng)面(mian)產生正(zheng)壓力(li),在建(jian)筑(zhu)(zhu)的(de)(de)各個(ge)側面(mian)及(ji)背(bei)(bei)面(mian)形(xing)成(cheng)負壓力(li)。屋(wu)頂自(zi)然(ran)通(tong)(tong)(tong)風(feng)器(qi)風(feng)壓通(tong)(tong)(tong)風(feng)就是利用建(jian)筑(zhu)(zhu)的(de)(de)迎(ying)(ying)風(feng)面(mian)和背(bei)(bei)風(feng)面(mian)之間的(de)(de)壓力(li)差(cha)實現空氣的(de)(de)流(liu)(liu)通(tong)(tong)(tong)。壓力(li)差(cha)是影響通(tong)(tong)(tong)風(feng)的(de)(de)關(guan)鍵因素。壓力(li)差(cha)的(de)(de)大小與建(jian)筑(zhu)(zhu)的(de)(de)造(zao)型、建(jian)筑(zhu)(zhu)周圍(wei)環境和建(jian)筑(zhu)(zhu)與風(feng)向的(de)(de)夾角有(you)關(guan)系(xi)。另外(wai),屋(wu)頂通(tong)(tong)(tong)風(feng)器(qi)流(liu)(liu)動(dong)空氣的(de)(de)壓力(li)隨其速(su)度的(de)(de)增加而減小,這(zhe)樣(yang)就形(xing)成(cheng)了低壓區。根據屋(wu)頂自(zi)然(ran)通(tong)(tong)(tong)風(feng)器(qi)的(de)(de)這(zhe)種原理(li),在設(she)計屋(wu)頂自(zi)然(ran)通(tong)(tong)(tong)風(feng)器(qi)時(shi),要注(zhu)意(yi)通(tong)(tong)(tong)風(feng)器(qi)的(de)(de)安裝位置。
2、熱壓作用下的自然通風
屋頂(ding)通(tong)(tong)(tong)風(feng)(feng)器的另一(yi)原(yuan)理是利(li)用(yong)(yong)(yong)(yong)建(jian)筑(zhu)(zhu)內(nei)(nei)(nei)部(bu)空(kong)氣(qi)的熱(re)壓差(cha)(cha),即(ji)通(tong)(tong)(tong)常講的“煙(yan)囪效應”來(lai)實(shi)現建(jian)筑(zhu)(zhu)的自然通(tong)(tong)(tong)風(feng)(feng)。利(li)用(yong)(yong)(yong)(yong)熱(re)空(kong)氣(qi)上(shang)升的原(yuan)理,在建(jian)筑(zhu)(zhu)上(shang)部(bu)設排(pai)(pai)風(feng)(feng)口(kou)可將(jiang)污濁的熱(re)空(kong)氣(qi)從(cong)室(shi)(shi)內(nei)(nei)(nei)排(pai)(pai)出,室(shi)(shi)外(wai)新鮮(xian)的空(kong)氣(qi)則從(cong)建(jian)筑(zhu)(zhu)周(zhou)圍的通(tong)(tong)(tong)風(feng)(feng)口(kou)被吸人。熱(re)壓作(zuo)用(yong)(yong)(yong)(yong)與進、出風(feng)(feng)口(kou)的高差(cha)(cha)和(he)室(shi)(shi)內(nei)(nei)(nei)外(wai)的溫(wen)(wen)差(cha)(cha)有(you)關(guan),室(shi)(shi)內(nei)(nei)(nei)外(wai)溫(wen)(wen)差(cha)(cha)和(he)進、出風(feng)(feng)口(kou)的高差(cha)(cha)越(yue)大,則熱(re)壓作(zuo)用(yong)(yong)(yong)(yong)越(yue)明顯。屋頂(ding)通(tong)(tong)(tong)風(feng)(feng)器在建(jian)筑(zhu)(zhu)設計中,可利(li)用(yong)(yong)(yong)(yong)建(jian)筑(zhu)(zhu)物內(nei)(nei)(nei)部(bu)貫(guan)穿多層的豎向空(kong)腔(qiang)。在夏季,可將(jiang)閥板打開,就像(xiang)是大型的天窗(chuang)。這樣,經過屋頂(ding)通(tong)(tong)(tong)風(feng)(feng)器冷卻的冷空(kong)氣(qi)便可吹向內(nei)(nei)(nei)部(bu),而室(shi)(shi)內(nei)(nei)(nei)的熱(re)空(kong)氣(qi)則由屋頂(ding)通(tong)(tong)(tong)風(feng)(feng)器排(pai)(pai)出。除此以外(wai),屋頂(ding)通(tong)(tong)(tong)風(feng)(feng)器還設有(you)調(diao)節(jie)室(shi)(shi)溫(wen)(wen)的啟閉(bi)系統。
二、屋頂通風器的優點
1、省電:屋(wu)頂通(tong)風(feng)器不需(xu)要使用電力,通(tong)過自然氣流實現通(tong)風(feng),具有節(jie)能環保(bao)的優點。
2、安全(quan):相比于電力驅動的通(tong)風(feng)設備(bei),屋頂通(tong)風(feng)器不易(yi)發生火災和(he)爆炸等事故,提(ti)高了安全(quan)性。
3、通(tong)風效果好(hao):屋頂通(tong)風器(qi)能(neng)夠通(tong)過自然氣(qi)流形成氣(qi)流循環,從而能(neng)夠有(you)效地排出內的有(you)害氣(qi)體和煙霧,保持(chi)空氣(qi)清新。
4、低(di)維護(hu)成本(ben):由于(yu)屋頂(ding)通風器沒有電動部分(fen),因此維護(hu)成本(ben)相對較低(di)。
5、安(an)裝方便:屋(wu)頂通風器的安(an)裝相對較簡單(dan),不需要進行復雜的電氣布線等(deng)工(gong)作。
三、屋頂通風器的缺點
1、受天氣影響(xiang)(xiang):屋頂通(tong)風(feng)器(qi)的(de)通(tong)風(feng)效(xiao)果(guo)會(hui)受到天氣因素的(de)影響(xiang)(xiang),如(ru)無風(feng)或風(feng)速較低時,通(tong)風(feng)效(xiao)果(guo)不佳。
2、不能精確調節:由于屋頂通(tong)(tong)風(feng)(feng)(feng)器(qi)不能精確調節通(tong)(tong)風(feng)(feng)(feng)量,因(yin)此(ci)在某些情況(kuang)下可能需要輔助使用其他通(tong)(tong)風(feng)(feng)(feng)設(she)備。
3、風(feng)噪音(yin)較大(da):在風(feng)速較高時(shi),屋頂通風(feng)器可能會產生較大(da)的噪音(yin),影(ying)響工作環境。
4、適用范圍有限:屋頂通風器的通風效果和受(shou)到大小和結(jie)構的限制,不適用于某些特殊(shu)工藝和環境(jing)。