Burn rate (chemistry)

About: Burn rate (chemistry) is a research topic. Over the lifetime, 847 publications have been published within this topic receiving 8908 citations. The topic is also known as: Burning rate.

Electronic Unit for Ultrasonic Solid-propellant Burn Rate Measurement System

Abstract: The paper envisages the development of a controlling electronic unit for the Ultrasonic Solid Propellant Burning Rate Measurement System (USBRMS). The electronic unit is an embedded system, consists of FPGA, ARM processor and Microcontrollers as its controlling parts. The product is designed and developed for the measurement of burning rate of solid propellant using in rocket motors. The system works on the principle of ultrasonic technique by measuring repeatedly the thickness of a cylindrical propellant specimen burning in a combustion chamber. User can measure the burning rate of different solid propellant samples using USBRMS system, which can be used for predicting the performance of large solid propellant motors used in space/strategic applications.

Improved propulsion system

Abstract: A propellant burning system and method useful in a rocket motor or projectile firing device burns a continuous main propellant grain (122) of relatively soft propellant material selected from uncatalyzed or partially catalyzed propellants. A separating device (112) divides the propellant grain into a large number of fragments of high-surface area during the burn and an activation mechanism (120, 124, 126) for causing said separating device to operate on the main propellant grain and to ignite and control the burning thereof.

Burn rate nanotube modifiers

Abstract: Nanotubular structures of high energy materials are used in high energy compositions, such as propellants.

Comprehensive Characterization of Pyrolysis and Combustion of Genista Salzmannii Needles (GSN) for Fire Hazard Analysis

Abstract: This article presents a first attempt of implementation of a lab scale methodology proposed to describe the thermal decomposition behavior of vegetative fuels, by using thermogravimetric (TG) methods, with respect to forest fire. Experiments within this method include testing the usual grinded form of samples compared to a continues fuel layer (intact form), which can render reliable and useful information to improve the understanding of the ignitability and combustibility of forest fuels along with predicting fire propagation. Moreover, slow (20 and 40 °C/min) and fast (60, 80 and 100 °C/min) heating rate were chosen to get close from the actual conditions of wildland fires (preheating/smoldering and flame region, respectively). In this work, we report the thermal decomposition behavior under inert (N2) and oxidative (air) atmospheres of Genista Salzmannii Needles (GSN) involved in fires of Mediterranean forests. TG analyses were performed to assess thermal reactivity and combustion indices (ignition, devolatilization, combustion and burnout indices) of grinded and cut GSN samples at fives heating rates of 20, 40, 60, 80 and 100 °C/min. The use of the set of thermal indices practical investigation, ignitability, combustibility and sustainability of forest fuels are important properties to be determined when talking to efficient wildland fire management. Moreover, Activation energy was calculated by means of two iso-conversional methods. The results showed that the cut GSN was characterized by a higher mass loss rate compared to grinded samples. As the heating rate increases, reactivity and combustion indices increase linearly. At low heating rates (20 and 40 °C/min), these parameters are quite similar for both samples, while the gap becomes more and more significant at elevated heating rates (60, 80 and 100 °C/min). High correlation coefficients (R2 > 0.96) were obtained, which indicate a good degree of fitting reliability between combustion characteristics and the tested heating rates. Furthermore, the variation of activation energy (Ea) with the conversion rate has exhibited a quite similar behavior during the whole pyrolysis and combustion process. Char formation, at the end of an intense devolatilization, was the most complex process. The oxidation of the remaining char was characterized by a significant decrease of Ea, which is not considered as a major event in the combustion process. Finally, the obtained data provide systematic knowledge for understanding the thermal decomposition of forest fuels (considered as the first stage in fire process), while the developed methodology can be used for comparison and classification of vegetative fuels related to fire risk potential.

A Novel Burn Rate Prediction Model of Rotating Solid Rocket Motors

Abstract: In solid rocket motors which rotate during operation, the combustion behavior is significantly different from ordinary motors because of centripetal acceleration. Most of the existing combustion rate prediction models are complex and require the support of material parameters and empirical parameters. To simplify the calculation while maintaining simulation accuracy, a novel burn rate prediction model, which tries to minimizes the physical simulation requirements and mainly relies on free parameters to fit actual burn rate distribution, is proposed in this article. The proposed model is proven to fit with the experiment data accurately, and doesn’t require fluid or thermo-chemical simulations.