A theory for flame extinction based on flame temperature

The extinction and suppression of diffusion flames is examined theoretically. The effects of oxygen reduction and external heat flux are examined compared to data in the literature. An application of extinction in compartment fires is also examined. The theory developed is based on a critical flame temperature, and that theory includes transient effects and the addition of water as well. Copyright © 2004 John Wiley & Sons, Ltd.     

An integrated model for predicting the flame propagation in crimped ribbon flame arresters

Crimped ribbon flame arresters are important safety devices in the chemical industry,especially for the dangerous situations.Although proper design of arresters by the numerical simulation method is promising,its reliability and accuracy are dependent upon the mathematical model.In this work,an integrated mathematical model for the microchannel in the crimped ribbon flame arresters was set up;the fluid flow behavior and the sensitivities of four chemical kinetics mechanisms of propane-air on the accuracy were analysed.It is shown that turbulence is predominant in the microchannel of the crimped ribbon flame arresters under the deflagration and detonation conditions,and a new quenching criterion for the numerical simulation is proposed.The kinetics mechanism of Mansouri et al.among the four ones is the most accurate due to the best agreement of the predicted outlet temperature at the experimental flameproof velocity with the autoignition temperature of propane-air.The species mass fraction profiles and the temperature distribution,which are too difficult to measure due to the tiny dimension of the microchannel in experiments,are captured.The fundamental insights into chemical reactions and heat loss are well portrayed.It can be concluded that the integrated mathematical model established in this work can be used as a reliable tool for modeling,selecting and designing such type of crimped ribbon flame arresters with the propane-air medium in the future.     

基于单片机的胎面自动称量系统

介绍采用8051单片机的胎面自动称量系统。该系统采用A/D574对采集到的胎面质量进行A/D转换,然后输入单片机并与键盘预先输入的工艺要求值进行比较,不符合要求的胎面则由翻送装置放入不合格区。该自动控制称量系统与原手动翻送装置相比,大大提高了生产效率,减轻了操作人员的劳动强度。     

基于PLC的厨余垃圾分选自动控制系统

在我国高速发展的经济条件下,环境问题成为大家普遍关注的问题。针对厨余垃圾的油腻,含水率高,有机物含量高等特点,本文以重庆市某厨余垃圾分选系统项目为例,详细介绍以西门子S7-1500 PLC为核心的自动控制系统的设计。项目实际应用表明,该控制系统实现了对厨余垃圾分选处理的自动化操作。     

基于CC-Link现场总线的脱腊装置控制系统的设计

从制腊生产的实际出发，阐述了以CC—Link现场总线为基础的脱腊装置控制系统的设计及其应用。     

Energy savings bottleneck diagnosis of cooling system based on integrated correlation analysis

The circulation cooling system is an important auxiliary system in industry and has great potential for saving energy. However, a holistic energy savings retrofit of the system can cause high costs and a low input–output ratio. To address this problem, this paper integrates grey correlation analysis and partial correlation analysis to propose a new energy savings bottleneck diagnosis method for the circulating cooling system. This method deeply analyzes the operation mechanism of the industrial circulating cooling system and summarizes the main energy-savings factor. Through the energy savings bottleneck diagnosis method based on grey correlation analysis and partial correlation analysis, the energy savings correlation coefficient and energy savings difference coefficient are calculated, and the relationship between each energy savings factor and the specific energy consumption is accurately described and quantified. Furthermore, the system energy savings bottleneck diagnosis is performed and the quantified energy savings priority of each system link is obtained. It can effectively guide the implementation of system energy savings optimization and retrofit. Finally, the effectiveness of the diagnosis method is demonstrated by simulation verification with actual network data.     

Reconstruction of electrical capacitance tomography images based on fast linearized alternating direction method of multipliers for two-phase flow system

Electrical capacitance tomography (ECT) has been applied to two-phase flow measurement in recent years. Image reconstruction algorithms play an important role in the successful applications of ECT. To solve the il-posed and nonlinear inverse problem of ECT image reconstruction, a new ECT image reconstruction method based on fast lin-earized alternating direction method of multipliers (FLADMM) is proposed in this paper. On the basis of theoretical analysis of compressed sensing (CS), the data acquisition of ECT is regarded as a linear measurement process of permittivity distribution signal of pipe section. A new measurement matrix is designed and L1 regularization method is used to convert ECT inverse problem to a convex relaxation problem which contains prior knowledge. A new fast alternating direction method of multipliers which contained linearized idea is employed to minimize the objective function. Simulation data and experimental results indicate that compared with other methods, the quality and speed of reconstructed images are markedly improved. Also, the dynamic experimental results in-dicate that the proposed algorithm can fulfil the real-time requirement of ECT systems in the application.     

硅橡胶阻燃材料的研究

分别探讨了氢氧化铝、氢氧化镁和硼酸锌等无机阻燃剂的用量对硅橡胶的阻燃性能及力学性能的影响。结果表明：当用量超过15份时，3种阻燃剂都能满足电缆附件的阻燃要求；在相同的用量下，氢氧化铝的阻燃性能优于氢氧化镁和硼酸锌；氢氧化铝用量为30份时，硅橡胶综合性能达到最佳。并且考察了软化剂1，2-丙二醇用量对硅橡胶综合性能的影响，得出其最佳用量为2份。     

Thermodynamic modeling of a nuclear energy based integrated system for hydrogen production and liquefaction

A nuclear based integrated system for hydrogen production and liquefaction with a newly developed four-step magnesium–chlorine cycle is proposed. The system uses nuclear energy to supply heat for the Rankine cycle and Mg–Cl cycle, where the power produced by the Rankine cycle is used to run the electrolysis steps of the Mg–Cl cycle and liquefaction cycle compressors. The four-step Mg–Cl cycle is specifically designed to decrease the electrical work consumption of the cycle by capturing HCl in dry form with an additional step to conventional three-step cycle. A performance assessment study is undertaken based on energy and exergy analysis of the subsystems, and total energy and exergy efficiencies of the plant are found to be 18.6%, and 31.35%. The comparisons of the subsystem efficiencies and total exergy destructions show that highest irreversibility ratio belongs to the Mg–Cl cycle by 41%, respectively.     

工程塑料阻燃体系市场发展概况

简要介绍了包括阻燃剂、阻燃工程塑料和抗滴落剂在内的工程塑料阻燃体系,分析了工程塑料用阻燃剂和抗滴落剂的市场发展概况,总结了阻燃工程塑料中不同基础树脂适用的阻燃剂.阻燃聚碳酸酯和丙烯腈-丁二烯-苯乙烯三元共聚物合金(PC/ABS)、阻燃聚碳酸酯(PC)主要使用双酚A-双磷酸二苯酯(BDP)等有机无卤磷系阻燃剂并添加抗滴落...