湖南大学学报（自然科学版）
湖南大學學報（自然科學版）
호남대학학보（자연과학판）
JOURNAL OF HUNAN UNIVERSITY(NATURAL SCIENCES EDITION)
2015年
1期
115-119
,共5页
频域有限差分法%内嵌管式辐射地板%频域热特性%CFD
頻域有限差分法%內嵌管式輻射地闆%頻域熱特性%CFD
빈역유한차분법%내감관식복사지판%빈역열특성%CFD
FDFD (frequency-domain finite-difference)model%pipe-embedded concrete radiant floor%frequency thermal characteristics%Computational Fluid Dynamics
基于经典有限差分原理建立了内嵌管式辐射地板的频域有限差分(FDFD)模型,同时采用Fluent软件建立了内嵌管式辐射地板的CFD模型作为参考模型,将内嵌管式辐射地板FDFD模型在典型频域点的计算结果转换成时域内的幅值与相角,并与CFD模型的计算结果进行对比.FDFD模型能准确预测内嵌管式辐射地板的热特性.采用FDFD模型进一步计算了不同厚度绝热层的辐射地板的频域热特性,分析了绝热层厚度对内嵌管式辐射地板热特性的影响.结果表明,在高频区域,绝热层厚度对地板传热的影响较小,而在低频区域内影响较为明显,尽管绝热层厚度取到40 mm,地板下表面仍存在较大的热流损失,约占管道热流的16%.
基于經典有限差分原理建立瞭內嵌管式輻射地闆的頻域有限差分(FDFD)模型,同時採用Fluent軟件建立瞭內嵌管式輻射地闆的CFD模型作為參攷模型,將內嵌管式輻射地闆FDFD模型在典型頻域點的計算結果轉換成時域內的幅值與相角,併與CFD模型的計算結果進行對比.FDFD模型能準確預測內嵌管式輻射地闆的熱特性.採用FDFD模型進一步計算瞭不同厚度絕熱層的輻射地闆的頻域熱特性,分析瞭絕熱層厚度對內嵌管式輻射地闆熱特性的影響.結果錶明,在高頻區域,絕熱層厚度對地闆傳熱的影響較小,而在低頻區域內影響較為明顯,儘管絕熱層厚度取到40 mm,地闆下錶麵仍存在較大的熱流損失,約佔管道熱流的16%.
기우경전유한차분원리건립료내감관식복사지판적빈역유한차분(FDFD)모형,동시채용Fluent연건건립료내감관식복사지판적CFD모형작위삼고모형,장내감관식복사지판FDFD모형재전형빈역점적계산결과전환성시역내적폭치여상각,병여CFD모형적계산결과진행대비.FDFD모형능준학예측내감관식복사지판적열특성.채용FDFD모형진일보계산료불동후도절열층적복사지판적빈역열특성,분석료절열층후도대내감관식복사지판열특성적영향.결과표명,재고빈구역,절열층후도대지판전열적영향교소,이재저빈구역내영향교위명현,진관절열층후도취도40 mm,지판하표면잉존재교대적열류손실,약점관도열류적16%.
A two-dimensional frequency-domain finite-difference (FDFD)model was developed on the basis of the classical finite-difference principle for a pipe-embedded concrete radiant floor to predict its fre-quency thermal responses.In the meantime,a CFD for this floor was also developed for this floor by using a reference model.The calculated frequency thermal responses of the floor by using FDFD model at typical frequency points were expressed in the form of amplitude and phase lag in time domain,and were then compared with the results by using CFD model.The results indicate that the FDFD model can predict the thermal characteristics accurately.The FDFD model was used to predict the frequency thermal characteris-tics of the pipe-embedded concrete radiant floor with insulation of different thicknesses,and the effects of the insulation thickness on the thermal responses of the pipe-embedded concrete radiant floor were analyzed and presented.The results indicate that the effect of the insulation thickness on the heat transfer of the floor is obvious in low frequency range while not obvious in high frequency range.Even if the thickness of the insulation is 40mm,the heat loss from the bottom surface of the floor constitutes about 1 6% of the heat transfer on the pipe surface and cannot be neglected.
