An experimental investigation of the effect of thermophysical properties on time lag and decrement factor for building elements

Year 2020, , 492 - 508, 01.06.2020

Hasan Oktay , Recep Yumrutaş , Zeki Argunhan

https://doi.org/10.35378/gujs.615322

Cited By: 7

Abstract

The time lag (TL) and decrement factor (DF) are essential for the heat storage capabilities of building elements, which strictly depend on the thermophysical properties of the elements. Many investigations are presented in literature arguing to find the influence of each thermophysical property on TL and DF by keeping the other properties constant. This study aims to investigate the effect of each property on TL and DF, utilizing relationships between the measurement values of the thermophysical properties of wall materials. Therefore, first, 132 new concrete wall samples were produced, and their thermophysical properties were tested. Secondly, TL and DF values for each building element are computed from the solution of the problem by Complex Finite Fourier Transform (CFFT) technique. Finally, a multivariate regression analysis has been performed, and the variations of each thermophysical property versus TL and DF are presented, and also the findings are compared with literature. The results show that each property alone (keeping the other properties constant) is not adequate to identify the thermal inertia and thermal performance of a wall element. Besides, 87.3 % decrease in thermal diffusivity corresponds to 6.03 h increase in the value of TL and 88.8 % decrease in value of DF; respectively, for W1 wall assembly. 

Keywords

Concrete, Time lag, Decrement factor, Thermophysical properties

References

• [1] Moosavi, L., Mahyuddin, N., Ghafar, N.A., Ismail, M.A., “Thermal performance of atria: An overview of natural ventilation effective designs”, Renew. Sustain. Energy Rev., 34: 654–670, (2014).
• [2] Sun, C., Shu, S., Ding, G., Zhang, X., Hu, X., “Investigation of time lags and decrement factors for different building outside temperatures”, Energy Build., 61: 1–7, (2013).
• [3] Mazzeo, D., Oliveti, G., Arcuri, N., “Influence of internal and external boundary conditions on the decrement factor and time lag heat flux of building walls in steady periodic regime”, Appl. Energy, 164: 509–531, (2016).
• [4] Gasparella, A., Pernigotto, G., Baratieri, M., Baggio, P., “Thermal dynamic transfer properties of the opaque envelope: Analytical and numerical tools for the assessment of the response to summer outdoor conditions”, Energy Build. 43: 2509–2517, (2011).
• [5] Ruivo, C. R., Ferreira, P. M., Vaz, D. C., “On the error of calculation of heat gains through walls by methods using constant decrement factor and time lag values”, Energy Build. 60: 252–261, (2013).
• [6] Mavromatidis, L. E., Mankibi, M. E., Michel, P., Santamouris, M., “Numerical estimation of time lags and decrement factors for wall complexes including Multilayer Thermal Insulation, in two different climatic zones”, Appl. Energy 92: 480–491, (2012).
• [7] Vijayalakshmi, M. M., Natarajan, E., Shanmugasundaram, V., “Thermal behaviour of building wall elements”, J. Appl. Sci., 15: 3128–3133, (2006).
• [8] Kaşka, Ö., Yumrutaş, R., Arpa, O., “Theoretical and experimental investigation of total equivalent temperature difference (TETD) values for building walls and flat roofs in Turkey”, Appl. Energy, 86: 737–747, (2009).
• [9] Stephan, E., Cantin, R., Caucheteux, A., Tasca-Guernouti, S., Michel, P., “Experimental assessment of thermal inertia in insulated and non-insulated old limestone buildings”, Build. Environ., 80: 241–248, (2014).
• [10] Ulgen, K., “Experimental and theoretical investigation of effects of wall's thermophysical properties on time lag and decrement factor”, Energy Build., 34: 273–278, (2002).
• [11] Asan, H.,” Investigation of wall’s optimum insulation position from maximum time lag and minimum decrement factor point of view”, Energy Build., 32 197–203, (2000).
• [12] Asan, H., “Effects of Wall's insulation thickness and position on time lag and decrement factor”, Energy Build., 28: 299-305, (1998).
• [13] Ozel, M., “Effect of insulation location on dynamic heat-transfer characteristics of building external walls and optimization of insulation thickness”, Energy Build., 72: 288–295, (2014).
• [14] Asan, H., “Numerical computation of time lags and decrement factors for different building materials”, Build. Environ., 41: 615–620, (2006).
• [15] Asan, H., Y.S. Sancaktar,” Effects of Wall’s thermophysical properties on time lag and decrement factor”, Energy Build 28: 159–166, (1998).
• [16] Zhang, Y., Lin, K., Zhang, Q., Di, H., “Ideal thermophysical properties for free-cooling (or heating) buildings with constant thermal physical property material”, Energy Build., 38: 1164–1170, (2006).
• [17] Kontoleon, K.J., Theodosiou, Th.G., Tsikaloudaki, K.G., “The influence of concrete density and conductivity on walls’ thermal inertia parameters under a variety of masonry and insulation placements”, Appl. Energy, 112: 325–337, (2013).
• [18] Yunsheng, X., Chung, D.D.L. , “Effect of sand addition on the specific heat and thermal conductivity of cement”, Cem. Concr. Res., 30: 59–61, (2000).
• [19] Khan, M.I., “ Factors affecting the thermal properties of concrete and applicability of its prediction models”, Build. Environ., 37: 607–614, (2002).
• [20] Oktay, H., Yumrutas, R., Akpolat, A., “Mechanical and thermophysical properties of lightweight aggregate concretes”, Constr. Build. Mater., 96: 217–25, (2015).
• [21] Unal, O., Uygunoglu, T., Yildiz, A., “Investigation of properties of low-strength lightweight concrete for thermal insulation”, Build. Environ., 42: 584–590, (2007).
• [22] H. Canakci, R. Demirboga, B. Karakoc, O. Sirin, Thermal conductivity of limestone from Gaziantep (Turkey), Build. Environ., 42: 1777–1782, (2007).
• [23] ACI Committee 122, Guide to Thermal Properties of Concrete and Masonry Systems, Ame. Concr. Inst., ISBN 9780870310850, (2002).
• [24] Jin, X., Zhang, X., Cao, Y., Wang, G., “Thermal performance evaluation of the wall using heat flux time lag and decrement factor”, Energy Build., 47: 369–374, (2012).
• [25] Zhang, Y., Du, K., He, J., Yang, L., Li, Y., Li, S., “Impact factors analysis on the thermal performance of hollow block wall”, Energy Build., 75: 330–341, (2014).
• [26] Yumrutas, R., Unsal, M., Kanoglu, M., “Periodic solution of transient heat flow through multilayer walls and flat roofs by complex finite Fourier transform technique”, Build. Environ., 40: 1117–25, (2005).
• [27] ASHRAE, ASHRAE handbook-fundamentals, ASHRAE, Atlanta, (1993).
• [28] Duffie, J.A., Beckman, W.A., Solar engineering of thermal process, fourth ed., Wiley, New York, (2013).
• [29] Mackey, C., Wright, L., “Periodic heat flow-homogeneous walls or roofs, ASHVE Transactions”, 50: 293–312, (1944).
• [30] Mackey, C., Wright, L., “Periodic heat flow-composite walls or roofs, ASHVE Transactions”, 52: 283–296, (1946).
• [31] Luo, C., Moghtaderi, B., Sugo, H., Page, A., “Time lags and decrement factors under air-conditioned and free-floating conditions for multi-layer materials”, 10th Conference of the International Build. Perform. Simul. Association, Beijing, 95-100, (2007).
• [32] Fidan, S., Oktay, H., Polat, S., Ozturk, S., “An Artificial Neural Network Model to Predict the Thermal Properties of Concrete Using Different Neurons and Activation Functions”, Adv. Mater. Sci. Engin., vol. (2019). https://doi.org/10.1155/2019/3831813.
• [33] TS EN 12667 Turkish Standards Institute, Thermal performance of building materials and products, (2003).
• [34] ASM International Materials Properties Database Committee, Thermal Properties of Metals, ISBN 0-87170-768-3, (2002).
• [35] Gagliano, A., Patania, F., Nocera, F., Signorello, C., “Assessment of the dynamic thermal performance of massive buildings”, Energy Build., 72: 361–370, (2014).
• [36] Barrios, G., Huelsz, G., Rechtman, R., Rojas, J., “Wall/roof thermal performance differences between air-conditioned and non air-conditioned rooms”, Energy Build., 43: 219–223, (2011).
• [37] Kossecka, E., “Correlations between structure dependent and dynamic thermal characteristics of building walls”, J. Build. Phys., 22: 315–333, (1999).