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Summary: The burning rate emulator (BRE) is a burner that emulates condensed fuel flames using gaseous fuel/inert mixtures by matching four properties: the heat of combustion; the heat of gasification; the laminar smoke point; and the surface temperature. Matching the heat of gasification requires measuring the burner heat flux, for which the BRE has embedded heat flux gauges and a copper top‐plate calorimeter. Seven condensed fuels were emulated: acetone, ethanol, methanol, polyethylene, polymethylmethacrylate, polypropylene, and polystyrene. The gaseous fuels were methane, ethylene, and propylene, diluted with nitrogen. Emulation data and flame images are shown to demonstrate emulation accuracy. A new method of emulation is developed that shifts the focus on which properties are prioritized and yields ~15% improvement in flame height. Calibration and use of the calorimeter are shown to have improved accuracy (within 5%) which provides confidence in the results. [ABSTRACT FROM AUTHOR]

The ASTM Standard Test Method E2584 'Standard Practice for Thermal Conductivity of Materials Using a Thermal Capacitance (Slug) Calorimeter' was developed by National Institute of Standards and Technology to measure thermal conductivity of fire-resistive and reactive materials during monotonic heating and cooling. The heating regime adopted in ASTM E2584 is very reasonable because change of materials' composition and structure during a fire can depend on kinetic factors and thermal story of the materials. The main problem in experimental measurements of thermophysical properties is the impossibility of using standard steady-state methods during time-dependent processes in materials accompanied by latent heat effect. Using standard transient methods, such as hot wire or laser flash methods, is also incorrect, because the transient measurement heat process can be started only after steady-state temperature field is established in the sample, that is, at the time when the involved physical or chemical processes could be finished. The objectives of this paper are to review and to analyze scientific problems to be taken into account in the revised version of ASTM E2584 Standard. Examples of experimental results are presented for measurement of thermophysical properties during chemical and physical processes in solid materials, powders, metals, and ceramic materials; building materials during fire; and so on. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The thermal properties of fire resistive materials (FRMs) as a function of temperature critically influence their ability to protect a (steel) structure during a fire exposure. Measurement of these properties is complicated by the microstructural heterogeneity of typical FRMs, the need to measure properties over a wide temperature range from room temperature to 1000°C and higher, and the reactions, phase changes, and volumetric changes that the materials may undergo during exposure to elevated temperatures. This paper presents an integrated approach for determining thermal properties via a combination of two experimental techniques, namely the transient plane source and the slug calorimeter methods. The former is utilized to provide an estimate of the volumetric heat capacity and a room temperature thermal conductivity value for the FRM under study, while the latter is employed to estimate the variation in effective thermal conductivity with temperature, including the influences of reactions and mass transport during multiple heating/cooling cycles. The combination of the two techniques is demonstrated for four different inorganic-based FRMs. Their extension to organic (intumescent) systems is also discussed. [ABSTRACT FROM AUTHOR]

This paper describes the first steps toward developing a highly-accurate multi-layered slug calorimeter for estimating the surface heat flux in high-enthalpy flows associated with hypersonic ground test campaigns. Slug geometry, material choices, test conditions, manufacturing method, mathematical modeling and instrumentation selection must be integrated into the design process in order to achieve the desired accuracy outcome. Integration is often overlooked in lieu of simplified data reduction equations that relate in-depth temperature measurements to the desired surface heat flux. Simplified models are often physics deficient and can lead to misleading interpretations. This paper illustrates the need for inclusive modeling in arriving at the data reduction equation for the heat flux gauge. Several important results are highlighted in this paper including the: (a) identification of data reduction model discrepancies; (b) significance of Volterra integral formulations for algorithm development; (c) implementation of a parameter-free preconditioner operated on data reduction model for low-pass filtering; (d) development of the approximation thread for uncertainty propagation; (e) achievement of stability through the future-time method; and, (f) extraction of the optimal regularization parameter through phase-plane and cross-correlation concepts for estimating the "best" heat flux. [ABSTRACT FROM AUTHOR]