Measurement of Instantaneous Mass Flow Rate of Polypropylene Gasification Products in Airflow

Abstract

A simple semi-empirical gas-dynamic approach for measuring the instantaneous mass flow rate of gasification products of low-melting solid material (polypropylene) in a flow-through gas generator with ambient-temperature air as gasifying agent is proposed. The approach is validated experimentally in the direct-connect facility allowing for the short-term (~0.5 s) heating of incoming air up to ~1700 K by hydrogen injection and ignition or by pyrotechnic charge activation. The application of the proposed method for processing experimental data for 9 (of over 100) selected typical test fires showed that the time-averaged total yield of polypropylene gasification products varied from 43 to 120 g/s, while the air-to-gasification product mass ratio was 2.3–2.9. The results of all conducted experiments confirm the applicability of the proposed approach for determining the mass flow rate of gasification products. The universality of the proposed approach is confirmed by applying two different schemes of gas generator: one with hydrogen ignition and another with pyro-charge ignition.