Pyrolysis Modelling of PVC Cable Materials

Abstract

One of the most commonly used materials in electrical cables is flexible PVC. In this work, the effects of the modelling decisions and parameter estimation methods on the pyrolysis modelling of two PVC cables were studied. The kinetic and thermal parameters were estimated from TGA and cone calorimeter experiments. The role of the plasticizers was shown to be important for the early HRR. The effects of the reaction path and reaction order were only minor in the TGA results but significant effects were found in the cone calorimeter results, unless a specific set of thermal parameters was estimated. The results show that the thermal parameters estimated for one kinetic model should not be used for another, unless the kinetic models only differ in fuel yields or different pairs of kinetic coefficients with same reaction order.

Combustion Characteristics of Materials and Generation of Fire Products

“…The model-specific material properties alluded to above are obtained by coupling a simplified pyrolysis model to optimization algorithms and the input parameters (i.e., the material properties) are adjusted in order to obtain the best possible agreement between model outputs and experimental bench-scale pyrolysis data. In the general framework of flammability properties this approach has been seldom used [68,69] although it has recently received renewed attention [70][71][72][73][74][75][76]. Numerous similar efforts, though, exist in the literature mostly aimed at determining a limited set of thermal properties and for specific applications [77][78][79][80][81][82].…”

“…Furthermore, availability of properties that can be easily measured (e.g., virgin density) will further improve the results by reducing the dimensionality of the problem. Yet, there are cases in the literature (e.g., [76]) where optimization is performed against very limited datasets. As a last word of caution it is reiterated that the "material properties" obtained using the methodology described herein depend on the choice of pyrolysis model as well as the accuracy of the experimental data and are not universally applicable to other models or to scenarios that considerably depart from the experimental conditions used to derive the model-specific properties.…”

Numerical Fire Spread Simulation Based on Material Pyrolysis - An Application to the CHRISTIFIRE Phase 1 Horizontal Cable Tray Tests

“…However, during the inverse modelling process (IMP) the conductor thickness was repeatedly pushed to its lower limit. This behaviour was also described by Matala and Hostikka [32]. Following that example, the conductor material layer was removed, to speed up the IMP by reduction of parameters.…”

A Multi-Scale Analysis of the Fire Problems in an Urban Utility Tunnel

“…Furthermore, the cone calorimeter test results of two other kinds of cables made of similar materials, have been compared. They are the NOKIA AHXCMK 10 kV 3 × 95/70 mm 2 [12,13] and the 7/C #12AWG 600V [10]. The detailed materials of their components are summarized in Table 2.…”

“…The burning characteristics of these cables thus could be very different. Unfortunately, only a few tests on similar cables used in nuclear power plants [12,13] could be found.…”