Combustion Performance Analysis

Nozzleless rockets are very simplified and low-cost rockets because no nozzles are used. Their specific impulse is lower than that of conventional rockets even when the same mass of propellant is used. Normally, a convergent-divergent nozzle is used to expand the chamber pressure to the atmospheric pressure through an isentropic change, which is the most effective process for converting pressure into propulsive thrust The flow process without a nozzle increases entropy and there is stagnahon pressure loss. 

Hybrid rockets are intermediate between solid rockets and hquid rockets in terms of the nature of the combination of solid fuel and hquid oxidizer. Since the fuel and oxidizer components of a Hquid rocket are physically separated, two mechanical systems are needed to feed these components into the combustion chamber. On the other hand, a hybrid rocket uses a polymeric inert material as a fuel and a Hquid oxidizer, and so only one mechanical system is needed to feed this Hquid oxidizer into the combusHon chamber. 

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Performance Analysis of a Family of Solid Propellants with Details of the Computer Programme and the Theoretical Method Used , Rept No RPE TN 225, Westcott (Engl) (1963) 6) S.A. Johnson et al, Research on Combustion of Solid Propellants , Rept No 641Q3, Contract DA-04-495-AMC-239(R), Lockheed Proplsn Co, Redlands(1964) 7) R.L.Coates, Research... 

The results of calculation of AP are presented in Fig. 23.5. It can be seen from AP along the length of the combustor, the elliptic nozzles provide better combustion performance than round nozzles. A better indicator of enhancement of supersonic mixing and combustion is obtained from the analysis of the impact of the fuel supply mode on the characteristic pressure-area integral for the diverging-area supersonic combustor [6, 7]. The combustion-induced pressure-area integrals for the 2D combustor (Fig. 23.1a) were calculated from the measured axial wall pressure distributions from the following relationship [7]... 

Crouse, F. W., Nazemi, A. H., and Lewis, J. P. Performance Analysis of a Pressurized Circulating Fluidized Bed Boiler Combined Cycle Power Plant, Proc. Int. Conf. Fluid. Bed Combust., Volume Data 1982, 7th(l), p. 232 (1983). 

With the previous combustion method, analysis is performed when carbon compounds are combusted in an oxygen-rich environment, resulting in the complete conversion of carbon to carbon dioxide. This procedure is not applicable to water samples with a very low concentration in elemental carbon as used for semiconductor manufacturing processes or required in pharmaceutical industries. For these cases the organic contaminants are measured by the total carbon... 

W. Richter, Scale-Up and Advanced Performance Analysis of Boiler Combustion Chambers, ASME paper No. 85-WA/HT-80, ASME, New York, 1985. 

Bischi, A., Langprgen, 0., Morin, J.-X. et al. (2011) Performance analysis of the cold flow model of a second generation chemical looping combustion reactor system. Energy Procedia, 4,449 56. 

Standard compounds have the same structures as QC compounds and are synthesized separately and purified by reversed-phase and normal-phase high-performance liquid chromatography (HPLC). After purification, standard compounds are rigorously characterized by H- and C-nuclear magnetic resonance (NMR) and LC-MS and their purity established as > 99.6% by combustion elemental analysis. 

Note, however, that vibration analysis and performance analysis may be linked in many instances. For example, a cracked combustion liner results in a change in TIT and PA calculations. As the cracked metal distxu-hs the airflow and is set into a vibration mode of its own, vibration sensors pick up indication of the cracked hner. Depending on the accuracy of the vibration probes, the sensors may pick up the problem before monitoring of gas path parameters. 

RCRA incinerator regulations include adrninistrative as weU as performance standards. Administrative standards include procedures for waste analysis, inspection of equipment, monitoring, and facihty security. Steps needed to meet adrninistrative standards are outlined ia the permit apphcation performance standards are demonstrated during a trial bum. Trial bum operating conditions are included in the permit to assure ongoing compliance with the performance standards. Performance standards include destmction and removal efficiency (DRE), particulate emissions limits, products of incomplete combustion emission limits, metal emission limits, and HCl and Cl emission limits (see Exhaust CONTROL, INDUSTRIAL). 

Figure 10.4 shows a schematic representation of the multidimensional GC-IRMS System developed by Nitz et al. (27). The performance of this system is demonstrated with an application from the field of flavour analysis. A Siemens SiChromat 2-8 double-oven gas chromatograph equipped with two FIDs, a live-T switching device and two capillary columns was coupled on-line with a triple-collector (masses 44,45 and 46) isotope ratio mass spectrometer via a high efficiency combustion furnace. The column eluate could be directed either to FID3 or to the MS by means of a modified Deans switching system . 

As discussed in Chapter 1, a portion of the feed is converted to coke in the reactor. This coke is carried into the regenerator with the spent catalyst. The combustion of the coke produces H2O, CO, CO, SO2, and traces of NOx. To determine coke yield, the amount of dry air to the regenerator and the analysis of flue gas are needed. It is essential to have an accurate analysis of the flue gas. The hydrogen content of coke relates to the amount of hydrocarbon vapors carried over with the spent catalyst into the regenerator, and is an indication of the rcactor-stripper performance. Example 5-1 shows a step-by-step cal culation of the coke yield. 

Catalytic combustion experiments have been performed in a flow reactor operating below the lower explosion limits using HC/02/He mixtures. The product analysis was done by gas chromatography. FT-IR spectra have been recorded with a Nicolet Magna 750 instrument, using conventional IR cells connected with evacuation-gas manipulation apparatus. The powder was pressed into self-supporting disks, calcined in air at 773 K and outgassed at 773 K for 20 minutes before experiments. 

Principles and Characteristics Combustion analysis is used primarily to determine C, H, N, O, S, P, and halogens in a variety of organic and inorganic materials (gas, liquid or solid) at trace to per cent level, e.g. for the determination of organic-bound halogens in epoxy moulding resins, halogenated hydrocarbons, brominated resins, phosphorous in flame-retardant materials, etc. Sample quantities are dependent upon the concentration level of the analyte. A precise assay can usually be obtained with a few mg of material. Combustions are performed under controlled conditions, usually in the presence of catalysts. Oxidative combustions are most common. The element of interest is converted into a reaction product, which is then determined by techniques such as GC, IC, ion-selective electrode, titrime-try, or colorimetric measurement. Various combustion techniques are commonly used. 

Simultaneous analysis of C, H, and N in liquid or solid organic materials may be carried out after combustion in an oxygen atmosphere at temperatures up to 1000 °C. The gaseous combustion products (CO2, H2O, N2) are flushed with a carrier gas (helium) through a reductant, and quantification is obtained by GC. For analysis of O, the combustion is performed in helium over platinised carbon. Carbon monoxide formed is converted to CO2 by passage over CuO, and measured in the same manner as for analysis of C. A 2-3 mg sample is required. 

Because hazardous waste combustion units are a type of TSDF, they are subject to the general TSDF standards in addition to combustion unit performance standards and operating requirements. Combustion units are also subject to specific waste analysis, inspection and monitoring, and residue management requirements. 

Analysis of griseofulvin, was determined for carbon, hydrogen, and chlorine. The carbon, and hydrogen analysis was performed on a Perkin Elmer Model 240 instrument. Analysis for chlorine was performed by combustion of the sample and coulometric titration using an American Instrument Co. 

Design practices stem from standard fire test procedures in which the temperature history of the test furnace is regarded as an index of the destructive potential of a fire. Thus, the practice of describing the expected effects and damage mechanism is based on temperature histories. This standard design practice is convenient but lacks accuracy in terms of structural performance. The severity of a fire should address the expected intensity of the heat flux that will impact the structure and the duration of heat penetration. A simple analysis of the expect nature of an unwanted fire can be based on the heats of combustion and pyrolysis of the principal contents in the facility. The heat of combustion will identify the destructive nature of the fire, while the heat of pyrolysis will identify the severity of the fire within the compartment itself and will also identify the destructive potential of the fire in adjacent spaces. 

CF-IRMS provides reliable data on micromoles or even nanomoles of sample without the need for cryogenic concentration because more of the sample enters the ion source than in DI-IRMS. CF-IRMS instruments accept solid, liquid, or gaseous samples such as leaves, soil, algae, or soil gas, and process 100-125 samples per day. Automated sample preparation and analysis takes 3-10 min per sample. The performance of CF-IRMS systems is largely determined by the sample preparation technology. A variety of inlet and preparation systems is available, including GC combustion (GC/C), elemental analyzer, trace gas pre-concentrator and other. The novel... 

The Dohrmann DX 20B system is based on combustion of the sample to produce the hydrogen halide, which is then swept into a microcoulometric cell and estimated. It is applicable at total halide concentrations up to lOOOpl-10 with a precision of 2% at the lOpg L-1 level. The detection limit is about 0.5pg L-1. Analysis can be performed in 5 min. A sample boat is available for carrying out analysis of solid samples. The instrument has been applied to waste waters, soils and sediments. 

Isotopic analysis of amino acids containing natural abundance levels of 15N was performed by derivatization, GC separation, on-line combustion and direct analysis of the combustion products by isotope-ratio MS. The N2 gas showed RSD better than 0.1%c for samples larger than 400 pmol and better than 0.5%o for samples larger than 25 pmol. After on-column injection of 2 nmol of each amino acid and delivery of 20% of the combustion products to the mass spectrometer, accuracy was 0.04%e and RSD 0.23%o19. 

Tobias et al. [665] have described a method in which the GC effluent is passed into a combustion furnace to convert the organic hydrogen content into water, which is then selectively reduced to hydrogen in a reduction furnace containing Ni metal. The final stream is transmitted to the IRMS via a heated Pd filter, which passes only hydrogen isotopes to the ion source. For a benzene sample a precision of < 5 %o was obtained for <52HSMOw> which approaches the performance of off-line techniques and the requirements for studies of natural variability. This already meets requirements for analysis of D-labeled compounds used in tracer studies [666,667]. 

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