Experimental Study of Thermal Behavior of Insulation Material Rigid Polyurethane in Parallel, Symmetric, and Adjacent Building Façade Constructions

Abstract

Both experimental and theoretical methods were proposed to assess the effects of adjacent, parallel, and symmetric exterior wall structures on the combustion and flame spreading characteristics of rigid polyurethane (PUR) foam insulation. During the combustion of PUR specimens, the flame leading edge was found to transfer from a unique inverted ‘W’ shape to an inverted ‘V’ during flame propagation. This phenomenon is attributed to edge effects related to boundary layer theory. The effects of the adjacent façade angle on flame spreading rate and flame height were shown to be nonlinear, as a result of the combined influences of heat transfer, radiation angle, and the chimney restriction effects. A critical angle around 90 degree with maximum thermal hazards outwards by parallel fire was observed and consistent with the mass loss rate and flame height tendencies. For narrow spacing configurations or angles (e.g., 60 and 90 degrees), phenomenological two-pass processing in conjunction showed that increased preheating lengths were associated with enhanced heat transfer. The results of this study have implications concerning the design of safe façade structures for high-rise buildings, and provide a better understanding of downward flame spreading over PUR.

Recent Trends of Foaming in Polymer Processing: A Review

“…Polymer foams are widely used in several industrial applications. For example, polyurethane (PU) soft foam can be used in furniture, composite fabrics, clothing, shoes and hats, car cushions, and sports equipment [13], while PU hard foam can be used in the production of refrigerators, freezers, and refrigerated containers [14,15]. Polypropylene (PP) foam is widely used in daily necessities, military industries, transportation, and aerospace, such as in the production of various seat cushions, thermal insulation materials, shockproof materials, packaging materials, and building materials [16,17,18].…”

Effect of Organic Cage Nucleating Agent Structure on Nucleating Efficiency and the Structure-Property Relationship

“…The specific strength [ 1 , 2 , 3 , 4 , 5 ] and dimensional stability of foaming materials [ 6 ] are directly related to cell density, which is determined by the number of cells present during the foaming process. Therefore, the quality of foaming materials can be effectively improved by regulating nucleation in the foaming process [ 7 , 8 , 9 , 10 , 11 , 12 ].…”

Influences of Sub-Atmospheric Pressure on Upward Flame Spread over Flexible Polyurethane Foam Board with Multiple Inclinations

“…For example, in China, one of the interests is based on the fire safety research for important historical or Buddhism buildings in the Qinghai-Tibet plateau. As the essential parameter related to oxidation and flow in combustion, pressure was confirmed to have obvious influences on fire spreading behavior and burning characteristics for solid fuels, e.g., wood [1][2][3][4], rigid polyurethane (RPU) foam [5,6], flexible polyurethane (FPU) foam [7][8][9], extruded polystyrene (XPS) [10,11], or other polymers [12][13][14]. Nowadays, more attentions are paid to fire behavior of these materials because of rapid development in the construction industry.…”