Thermal conductivity and heat transfer coefficient of concrete

Abstract

A very simple model for predicting thermal conductivity based on its definiensis was presented. The thermal conductivity obtained using the model provided a good coincidence to the investigations performed by other authors. The heat transfer coefficient was determined by inverse analysis using the temperature measurements. From experimental results, it is noted that heat transfer coefficient increases with the increase of wind velocity and relative humidity, a prediction equation on heat transfer coefficient about wind velocity and relative humidity is given.

Keywords

thermal conductivity / heat transfer coefficient / relative humidity / wind velocity

References

[1] Morabito P. Measurement of the Thermal Properties of Different Concretes [J]. High Temp. High Press, 1989, (21):51–59

[2] Nevile A.M. Properties of Concrete [M], 1995 UK Longman 50-60.

[3] ACI Committee 207. Mass Concrete, ACI Manual of Concrete Practice, Part 1[R], 1994 Detroit American Concrete Institute

[4] Kim Kook-Han, Jeon Sang-Eun, Kim Jin-Keun, et al. An Experimental Study on Thermal Conductivity of Concrete[J]. Cement and Concrete Research, 2003, (33):363–371

[5] Branco F.A., Mendes P.A., Mirambell E. Heat of hydration effects in concrete structures[J]. ACI Mater.J., 1992, 89(2): 139-145.

[6] Mendes P. Temperature Gradients for Concrete Bridges [D], 1989 Lisbon Technical University 89

[7] Lee Yun, Choi Myoung-Sung, Yi Seong-Tae, et al. Experimental Study on the Convective Heat Transfer Coefficient of Earlyage Concrete[J]. Cement & Concrete Composites, 2009, (31): 60–71

[8] Zhu B.F. Thermal Stresses and Temperature Control of Mass Concrete [M], 1998 Beijing China Electric Power Press 12-17.

[9] MB A.-e.-M., MM Helal. Group Method Solution for Solving Nonlinear Heat Diffusion Problems [J]. Applied Mathematical Modeling, 2006, 30(9): 930-940.

[10] Lanciani A, Morabito P, Rossi P. Measurement of the Thermo Physical Properties of Structural Materials in Laboratory and in site: Methods and Instrumentation [J]. High Temp High Press, 1989, (21): 391–400

[11] Japan Concrete Institute. The Measuring Methods of Conductivity, Diffusivity and Specific heat of Concrete and Their Application[M]. J. Jpn. Concr, Inst. Mass Concr. Div, 1982

[12] Liley P.E. Steam Table in SI Units, Private communication [M], 1978 West Lafayette Purdue University

[13] Epifanov A.P., Lukyanov A.T., Rozenfeld G.O., . Heat Transfer of Concrete Through External Surfaces [J]. Power Technology and Enginee-ring, 1974, 8(5): 438-440.

[14] Dorignac E. Experimental Heat Transfer on the Windward Surface of a Perforated Flat Plate [J]. International Journal of Thermal Sciences, 2005, (44): 885–894

[15] Ozawa S. Study on the Early Age Cracking of Massive Concrete and Its Prevention Measure [J]. Water Power for Electric Generation,1962,(57): 254–261

[16] Holman J.P., Gajda W.J. Jr. Experimental Methods for Engineers [M], 1989 New York McGraw-Hill 37-83.

[17] Kim K.H., Jeon S.E., Kim J.K., Yang S.C. An Experimental Study on Thermal Conductivity of Concrete[J]. Cement Concrete Research, 2003, 33(3): 363-371.