Vaporizing and Endothermic Fuels for Advanced Engine Application. Part I. Preliminary Studies of Catalized Reactions and Thermal Stabilities of Hydrocarbon Fuels PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Vaporizing and Endothermic Fuels for Advanced Engine Application. Part I. Preliminary Studies of Catalized Reactions and Thermal Stabilities of Hydrocarbon Fuels PDF full book. Access full book title Vaporizing and Endothermic Fuels for Advanced Engine Application. Part I. Preliminary Studies of Catalized Reactions and Thermal Stabilities of Hydrocarbon Fuels by A. C. Nixon. Download full books in PDF and EPUB format.
Author: A. C. Nixon Publisher: ISBN: Category : Languages : en Pages : 185
Book Description
Studies leading toward the development of specifications for heat sink fuels for hypersonic aircraft are reported. Consideration of the effect of design parameters on the conditions under which endothermic reactions can be carried out has led to the conclusion that space velocities of 50 or higher would be necessary due to volume limitations in high-speed aircraft. Rate considerations favor catalytic reactions. Preliminary studies of the dehydrogenation of propane to propene and methylcyclohexane to toluene were made, and dehydrocyclization of various paraffins attempted. Thermal stability studies include the modification of two types of cokers to minimize contamination possibilities and improve reproducibility. Fuels may be tested at temperatures up to at least 1000F. The thermal stabilities of samples of n-dodecane, toluene and methylcyclohexane decreased in the order named. A 25 gal/hr fuel system simulation test rig which will be used for determining heat transfer coefficients, heat sinks and product compositions has been designed. (Author).
Author: A. C. Nixon Publisher: ISBN: Category : Languages : en Pages : 185
Book Description
Studies leading toward the development of specifications for heat sink fuels for hypersonic aircraft are reported. Consideration of the effect of design parameters on the conditions under which endothermic reactions can be carried out has led to the conclusion that space velocities of 50 or higher would be necessary due to volume limitations in high-speed aircraft. Rate considerations favor catalytic reactions. Preliminary studies of the dehydrogenation of propane to propene and methylcyclohexane to toluene were made, and dehydrocyclization of various paraffins attempted. Thermal stability studies include the modification of two types of cokers to minimize contamination possibilities and improve reproducibility. Fuels may be tested at temperatures up to at least 1000F. The thermal stabilities of samples of n-dodecane, toluene and methylcyclohexane decreased in the order named. A 25 gal/hr fuel system simulation test rig which will be used for determining heat transfer coefficients, heat sinks and product compositions has been designed. (Author).
Author: A. C. Nixon Publisher: ISBN: Category : Catalysts Languages : en Pages : 558
Book Description
Studies leading toward the development of specifications for heat-sink fuels for hypersonic aircraft are reported. Heat sinks of about 2000 Btu/lb of fuel can be achieved at 1350 F by taking advantage of latent, sensible, and endothermic heat sinks. Rate considerations favor catalytic reactions. The dehydrogenation of methylcyclohexane (MCH) to toluene and hydrogen approaches the above heat sink over a platinum on alumina catalyst. Propane dehydrogenation will yield about 1500 Btu/lb, but the reaction is neither as clean nor as rapid. The thermal stabilities of molecular types generally increase in the order monocyclic aromatic, monocyclic naphthene, bicyclic naphthene, n-paraffin. Exclusion of oxygen increases the critical thermal stability temperature by about 200 F. The introduction of alkyl groups into either the cyclohexane or benzene rings increases thermal stability. A 20-gal/hr adiabatic heat exchanger-reactor system has been constructed and shakedown tests with water have been completed following the execution of a number of changes suggested by preliminary test work. Excellent heat balances have been achieved and satisfactory correlation of heat-transfer data with the literature has been found. Ignition delay data have been obtained utilizing a single-diaphragm shock tube under conditions useful for consideration in the design of supersonic combustion ramjets. Methylcyclohexane and its reaction products and propane and its reaction products have been studied in the range 1300-2700 F. Ignition delays ranged from 100-4000 microseconds under lean conditions, decreasing with temperature. (Author).
Author: A. C. Nixon Publisher: ISBN: Category : Chemical reactions Languages : en Pages : 381
Book Description
Investigation of the feasibility of using endothermic reactions to augment the latent and sensible heat of fuels for cooling engines operating under a high mach number regime is continuing. Studies in the literature continue to maintain the desirability and feasibility of producing vehicles with hypersonic flight speeds and suggest some areas of advantage of hydrocarbons. Laboratory studies on the dehydrogenation over Pt/Al2O3 of a number of mixtures of naphthenes have been made including methyl-Decalin and dicyclohexyl as well as the pure components, with additional studies on Decalin. About 220 dehydrogenation catalysts have been prepared using a variety of metals and supports. Propane and an advanced jet fuel were tested as possible heat sink fuels in our fuel system simulation test reactor under thermal cracking conditions. Our packed bed reactor program included herein, has been rewritten and simplified resulting in a considerable saving in both human and computer time. The thermal stability of MCH, Decalin and a naphthenic jet fuel were all critically, but uniquely, dependent on O2 concentration in the region below about 10 ppm. The ignition delay behavior of both ethane and ethylene was found to be considerably different from other hydrocarbons in the shock tube, the ignition delay reaching a minimum in the region of E/R = 0.5 with two different temperature coefficients which are dependent upon total reactives concentration.
Author: A. C. Nixon Publisher: ISBN: Category : Catalysts Languages : en Pages : 401
Book Description
Investigation of the feasibility of using endothermic reactions of hydrocarbons to augment the latent and sensible heat of fuels for cooling engines operating under a high mach number regime is continuing. The dehydrogenation of Decalin over a platinum/Al2O3 catalyst has been studied extensively on a laboratory scale covering the temperature region up to 1200F and pressures to 10 atms, in order to provide kinetic data for the construction of a mathematical model. Production of catalysts have turned up a number of the 536 catalysts examined that are more active than the standard Pt/Al2O3 catalyst, but no breakthrough in either activity or cost has been achieved. Further testing has shown that catalysts which demonstrate improved activity with MCH do the same with Decalin and has confirmed the observation that improved catalyst stability is associated with small pore size. Heat transfer studies in a simulated single tube fuel system have confirmed the mathematical model for the catalytic dehydrogenation of MCH up to a heat flux of 600,000 Btu/hr/sq ft. The thermodynamic and transport properties of trans-Decalin, Shelldyne and JP-7 and a bibliography of recent literature of interest are included.
Author: A. C. Nixon Publisher: ISBN: Category : Catalysts Languages : en Pages : 284
Book Description
The investigation of the feasibility of utilizing the endothermic and enthalpic capacity of hydrocarbons to fuel and cool high speed aircraft is continued. Calculation of the cooling requirement for a Mach 8 supersonic combustion ramjet engine under standard conditions indicate that this would be about 1900 Btu per pound of fuel. The possibility of utilizing the dehydrogenation of bridged-ring naphthenes for providing additional heat sink has been studied but no suitable catalysts have been found for this reaction. Studies on methods accelerating the thermal cracking of paraffins by means of additives has shown some promise. In the dehydrogenation of naphthenes over supported platinum catalysts the stability of the catalyst was found to be inversely proportional to the pore size of the support, and is also affected by the composition of the support. Efforts to induce the dehydrogenation of methylcyclohexane using dispersed catalysts has met with some success. Also quite marked variations in the rate and type of reaction have been observed depending on the type and source of the metal used for the reactor tube. A large number of additional granular catalysts have been tested for their activity in dehydrogenation of MCH.
Author: A. C. Nixon Publisher: ISBN: Category : Fuel Languages : en Pages : 307
Book Description
Investigation of the feasibility of utilizing hydrocarbons as heat-sink fuels for hypersonic aircraft has continued. Both thermal and catalytic endothermic reactions have been considered, at temperatures up to 1400 F, pressures to 1000 psi, liquid hourly space velocities up to 260 and 150, respectively. Mono- and dicyclic naphthenes appear to be the most promising feeds to date. Utilizing dehydrogenation to the corresponding aromatics over a platinum on alumina catalyst, reaction heat sinks of about 1000 Btu/lb of feed should be achievable with the lower members of the series, such as cyclohexane, methylcyclohexane, dicyclohexyl, and decalin. Laboratory studies have been made on the dehydrogenation of a wide variety of naphthenes over Pt/Al2O3 catalysts to determine approximate reaction kinetics and selectivities. Rates of reaction generally increase with alkyl substitution. Activation energies show variable behavior. Selectivities for the corresponding aromatics are high. Some problems with catalyst life and consecutive reactions have been encountered; some solutions have been found.
Author: A. C. Nixon Publisher: ISBN: Category : Languages : en Pages : 262
Book Description
The document is comprised of figures, tables and other data in support of the basic report, AD-867 045. A bibliography of 1502 items is included.
Author: A. C. Nixon Publisher: ISBN: Category : Languages : en Pages : 327
Book Description
Investigation of the feasibility of utilizing hydrocarbons as heat-sink fuels for hypersonic aircraft has continued. Both thermal and catalytic endothermic reactions have been considered, at temperatures up to 1400 F, pressures to 1000 psi, liquid hourly space velocities up to 260 and 150, respectively. Mono- and dicyclic naphthenes appear to be the most promising feeds to date. Utilizing dehydrogenation to the corresponding aromatics over a platinum on alumina catalyst, reaction heat sinks of about 1000 Btu/lb of feed should be achievable with the lower members of the series, such as cyclohexane, methylcyclohexane, dicyclohexyl, and decalin. Laboratory studies have been made on the dehydrogenation of a wide variety of naphthenes over Pt/Al2O3 catalysts to determine approximate reaction kinetics and selectivities. Rates of reaction generally increase with alkyl substitution. Activation energies show variable behavior. Selectivities for the corresponding aromatics are high. Some problems with catalyst life and consecutive reactions have been encountered; some solutions have been found.
Author: A. C. Nixon
Author: A. C. Nixon
Author: A. C. Nixon
Author: A. C. Nixon
Author: A. C. Nixon
Author: A. C. Nixon
Author: A. C. Nixon
Author: A. C. Nixon
Author: A. C. Nixon
Author: 
Author: Defense Documentation Center (U.S.)