中国电机工程学报
中國電機工程學報
중국전궤공정학보
ZHONGGUO DIANJI GONGCHENG XUEBAO
2011年
23期
67-73
,共7页
超临界锅炉%光管%内螺纹管%临界压力区%传热%恶化
超臨界鍋爐%光管%內螺紋管%臨界壓力區%傳熱%噁化
초림계과로%광관%내라문관%림계압력구%전열%악화
supereritical internally ribbed tube%near transfer deterioration pressure boiler%smooth tube%critical pressure region%heat
在压力p=19.0-22．5MPa，管内质量流速（7=540-1200kg／（m2·s），内壁热流密度q=150-650kW／m2的参数范围内，对垂直上升管内水在临界压力区的传热恶化进行了比较系统的试验研究。在试验的基础上，结合前人研究数据，对临界压力区内，水在垂直上升光管和内螺纹管内的沸腾传热恶化进行了比较全面的对比、分析。研究发现，不论是光管还是内螺纹管，在临界压力区p／p。r=0．96-0．98的区域内最易发生膜态沸腾（departurefromnucleateboiling，DNB），即发生传热恶化的临界干度最小；随着压力接近临界压力，内螺纹管的传热特性有变坏的趋势，其抑制DNB的能力有所降低：内螺纹管抑制DNB的能力主要取决于内螺纹管的结构参数，采用具有更大旋流作用的螺纹结构，有助于改善其传热性能。
在壓力p=19.0-22．5MPa，管內質量流速（7=540-1200kg／（m2·s），內壁熱流密度q=150-650kW／m2的參數範圍內，對垂直上升管內水在臨界壓力區的傳熱噁化進行瞭比較繫統的試驗研究。在試驗的基礎上，結閤前人研究數據，對臨界壓力區內，水在垂直上升光管和內螺紋管內的沸騰傳熱噁化進行瞭比較全麵的對比、分析。研究髮現，不論是光管還是內螺紋管，在臨界壓力區p／p。r=0．96-0．98的區域內最易髮生膜態沸騰（departurefromnucleateboiling，DNB），即髮生傳熱噁化的臨界榦度最小；隨著壓力接近臨界壓力，內螺紋管的傳熱特性有變壞的趨勢，其抑製DNB的能力有所降低：內螺紋管抑製DNB的能力主要取決于內螺紋管的結構參數，採用具有更大鏇流作用的螺紋結構，有助于改善其傳熱性能。
재압력p=19.0-22．5MPa，관내질량류속（7=540-1200kg／（m2·s），내벽열류밀도q=150-650kW／m2적삼수범위내，대수직상승관내수재림계압력구적전열악화진행료비교계통적시험연구。재시험적기출상，결합전인연구수거，대림계압력구내，수재수직상승광관화내라문관내적비등전열악화진행료비교전면적대비、분석。연구발현，불론시광관환시내라문관，재림계압력구p／p。r=0．96-0．98적구역내최역발생막태비등（departurefromnucleateboiling，DNB），즉발생전열악화적림계간도최소；수착압력접근림계압력，내라문관적전열특성유변배적추세，기억제DNB적능력유소강저：내라문관억제DNB적능력주요취결우내라문관적결구삼수，채용구유경대선류작용적라문결구，유조우개선기전열성능。
The heat transfer deterioration of water in near critical pressure region in vertically upward tubes was investigated experimentally. The pressure at the inlet of the test section ranged from 19.0 to 22.5 MPa, the mass flux of the fluid was from 540 to 1 200 kg/（m2-s）, and the heat flux on the inside wall of the tube was varied from 150 to 650 kW/m2. According to the experimental data, a systematic analysis and comparison was made on the heat transfer deterioration in the near critical pressure region inside the vertically upward internally ribbed tubes and the smooth tubes. It is suggested that the critical steam quality of the heat transfer deterioration is the smallest at the ratio p/pcr=0.96-0.98 whether in the internally ribbed tubes or in the smooth tubes. With the pressure close to the critical pressure of water, the capacity of the internally ribbed tube for enhancing heat transfer and inhibiting DNB decrease. The capacity of the internally ribbed tube for inhibiting DNB mainly depends on the structure parameters of the internally-ribbed tube.
