Seven performance parameters of cone calorimeter

Seven performance parameters of cone calorimeter

1. Mass Loss Rate (Mass Loss Rate, MLR for short)

MLR refers to the rate of change of the mass of the burning sample over time during the combustion process, and it reflects the degree of thermal cracking, volatilization and combustion of the material under a certain fire intensity. The MLR value is calculated by a 5-point numerical differential equation. The unit of MLR is g/s. In addition to the mass loss rate, the mass loss curve can also be obtained from CONE, so as to obtain the residual mass at different times, which is convenient for visual analysis of the cracking behavior of the combustion sample.

2. Smoke Produce Rate (SPR)

SPR is defined as the ratio of specific extinction area to mass loss rate, in m2/S, where SEA is the specific extinction area (Specific Extinction Area), SEA represents the smoke produced by volatilizing a unit mass of material, it does not directly represent the production The amount of smoke is just a conversion factor for calculating the amount of smoke, and the unit is m?/kg. Similarly, the total smoke rate (Total Smoke Rate) can be obtained by integrating, TSR=∫SPR, TSR represents the cumulative total smoke generated when a unit sample area is burned, and the unit is m?/m?.

3. Effective Heat Combustion (EHC)

EHC represents the ratio of the measured heat release rate to the mass loss rate at a certain time t. It reflects the degree of combustion of volatile gases in the gas phase flame and is very helpful for analyzing the flame retardant mechanism. The unit of EHC is MJkg-1.

4. Time to Ignition (TTI)

TTI is an important parameter (unit: s) for evaluating the fire resistance of a material. It refers to the time from the surface of the material being heated to the continuous burning of the surface under the preset intensity of the incident heat flow. TTI can be used to evaluate and compare the fire resistance of materials.

5. Toxicity determination

When the material burns, it emits a variety of gases, including CO, HCN, SO2, HCl, H2S and other toxic gases. Toxic gases have a great harmful effect on the human body. The composition and percentage content can be added to the cone calorimeter. Equipment collection and analysis.

6. Heat Relea se Rate (HRR for short)

HRR refers to the heat release rate per unit area after the material is ignited under the preset intensity of incident heat flow.

HRR is the most important performance parameter to characterize fire intensity, and its unit is kW/m2; the maximum value of HRR is the peak of heat release rate (Peak of HHR, referred to as pkHRR), and the size of pkHRR characterizes the maximum heat release degree when the material burns. The greater the HRR and pkHHR, the greater the burning heat of the material and the greater the fire hazard.

7. Total Heat Release (THR)

THR refers to the total amount of heat released by the material from ignition to flame extinguishment under the preset intensity of incident heat flow, and the unit is MJ/m?. Combining HRR and THR can better evaluate the flammability and flame retardancy of materials, and have a more objective and comprehensive guiding role for fire research.