【摘要】：為保證安全殼在LOCA、MSLB等極限事故工況下的完整性，新一代核反應(yīng)堆廣泛采用了非能動(dòng)安全殼冷卻系統(tǒng)。對(duì)于基于雙層混凝土安全殼的非能動(dòng)安全殼冷卻系統(tǒng)，位于安全殼內(nèi)的冷凝器是其最關(guān)鍵的設(shè)備之一，其傳熱能力決定著非能動(dòng)安全殼冷卻系統(tǒng)的性能。在蒸汽冷凝過(guò)程中，安全殼內(nèi)大量不凝性氣體的存在會(huì)導(dǎo)致傳熱嚴(yán)重惡化，所以必須對(duì)含不凝性氣體的蒸汽冷凝傳熱問(wèn)題開(kāi)展相關(guān)的研究工作。 本文對(duì)豎直光管管外含空氣蒸汽冷凝的傳熱特性進(jìn)行了實(shí)驗(yàn)研究和數(shù)值模擬研究，實(shí)驗(yàn)研究分析了混合氣體壓力、壁面過(guò)冷度、空氣含量對(duì)蒸汽在豎直管管外冷凝傳熱性能的影響規(guī)律，給出了含空氣蒸汽的冷凝傳熱過(guò)程中的經(jīng)驗(yàn)關(guān)聯(lián)式。試驗(yàn)結(jié)果表明，僅考慮單一因素對(duì)冷凝的影響時(shí)，管外冷凝傳熱系數(shù)隨混合氣體壓力的升高而增大；隨空氣質(zhì)量分?jǐn)?shù)的升高，管外冷凝傳熱系數(shù)成指數(shù)的規(guī)律遞減；管外冷凝傳熱系數(shù)與壁面過(guò)冷度的0.6次方成反比關(guān)系。本文得到的管外冷凝傳熱系數(shù)經(jīng)驗(yàn)關(guān)聯(lián)式與實(shí)驗(yàn)值的最大偏差在±10%以內(nèi)，與現(xiàn)有的經(jīng)驗(yàn)關(guān)聯(lián)式相比，該關(guān)聯(lián)式具有更廣的適用范圍。 利用計(jì)算流體力學(xué)（CFD）軟件通過(guò)UDF編程在控制方程中加載源項(xiàng)的方法實(shí)現(xiàn)了對(duì)含空氣蒸汽冷凝的數(shù)值模擬研究。通過(guò)將3個(gè)壓力工況下的9組數(shù)值計(jì)算結(jié)果與試驗(yàn)值對(duì)比，得到冷凝傳熱系數(shù)的最大相對(duì)誤差為28.59%，平均溫度的最大誤差為3.75℃，平均壓力及空氣質(zhì)量分?jǐn)?shù)的相對(duì)誤差都在1%以內(nèi)，說(shuō)明本文的模擬方法具有一定的精度。數(shù)值模擬結(jié)果表明，在本文實(shí)驗(yàn)條件下，潛熱換熱是冷凝傳熱的主導(dǎo)因素；潛熱換熱系數(shù)及顯熱換熱系數(shù)都隨著空氣含量的升高而減小；局部潛熱換熱系數(shù)沿傳熱管高度方向從下至上呈遞減趨勢(shì)，，而局部顯熱換熱系數(shù)則呈現(xiàn)相反變化。在此基礎(chǔ)上，應(yīng)用本文模擬方法對(duì)TOSQON試驗(yàn)進(jìn)行模擬，模擬結(jié)果和實(shí)驗(yàn)結(jié)果的相對(duì)誤差在10%以內(nèi)，證明本文模擬方法及冷凝傳熱系數(shù)經(jīng)驗(yàn)關(guān)聯(lián)式在其他實(shí)驗(yàn)條件下也有很好的適用性。
[Abstract]:In order to ensure the integrity of containment under limited accident conditions such as LOCAN MSLB, the new generation of nuclear reactors have widely used inactive containment cooling system. For the non-active containment cooling system based on double-layer concrete containment, the condenser located in the containment is one of its most important equipments, and its heat transfer ability determines the performance of the non-active containment cooling system. In the process of steam condensation, the existence of a large number of non-condensable gases in containment will lead to a serious deterioration of heat transfer, so it is necessary to carry out relevant research work on the condensation heat transfer of steam containing non-condensable gases. In this paper, the heat transfer characteristics of air vapor condensing outside vertical smooth tube are studied experimentally and numerically. The pressure of mixed gas and the undercooling degree of wall are analyzed experimentally. The effect of air content on the condensing heat transfer performance of steam outside the vertical tube is studied. The empirical correlation of condensing heat transfer with air vapor is given. The experimental results show that the external condensation heat transfer coefficient increases with the increase of the pressure of the mixed gas, and decreases exponentially with the increase of air mass fraction when considering the effect of a single factor on the condensation. The condensation heat transfer coefficient outside the tube is inversely proportional to the 0.6 power of the wall undercooling degree. The maximum deviation between the empirical correlation and the experimental value of the external condensation heat transfer coefficient obtained in this paper is less than 鹵10%. Compared with the existing empirical correlation, the correlation has a wider range of application. The numerical simulation of vapor condensation with air was carried out by means of the method of loading source term into the governing equation by UDF programming with computational fluid dynamics (CFD) software. The maximum relative error of condensation heat transfer coefficient is 28.599.The maximum error of average temperature is 3.75 鈩

本文編號(hào)：2119356