Combustion Effects of Coal Liquid and Other Synthetic Fuels in Gas Turbine Combustors: Part I — Fuels Used and Subscale Combustion Results

Combustion tests on over twelve types of coal derived liquid fuels from the EDS, H-coal, SRC-I and SRC-II processes and three shale oil fuels have been conducted in gas turbine type combustors. Emission measurements were made of Nox, smoke, CO, and unburned hydrocarbons. Combustor wall temperature profiles were measured. The results are correlated with the fuel properties-percent nitrogen, hydrogen and aromaticity. This part of the paper discusses the fuels used in subscale combustion tests along with the test results. A companion paper (Part II) describes the results of full-scale combustor tests and a long term corrosion/deposition test.

Selection of a Closed Brayton Cycle Gas Turbine for an Intermediate-Duty Solar-Electric Power Plant

Subsystem and system analyses were performed to select the preferred working gas, performance characteristics and size of a closed cycle gas turbine for an intermediate-duty solar-electric power plant. Capital costs for all major subsystems were evaluated, but the principal selection criterion was the projected cost of electricity produced by the plant. Detailed analyses of the power conversion loop were conducted for both air and helium systems. Since the plant was intended for use on an intermediate-duty cycle, thermal storage was required. The coupling of the storage and power conversion loops in combination with the daily operating cycle influenced plant performance and energy costs in addition to the selection of the power conversion cycle. This work was done under contract of DOE as part of the Advanced Solar Electric Central Receiver Program.

Operation and Test of a New 37 MW Gas Turbine Package Power Plant

A new 37-MW, single-shaft gas turbine power plant has been designed for electric power generation, for use in either simple-cycle or combined-cycle applications. This paper describes the design features, instrumentation, installation, test, and initial operation.

Smoke Characteristics of Distillate and Residual Fuel Burning in Gas Turbine Combustors

During the development of a rich-lean staged dry low NOx combustor, the conventional trend of increasing smoke with increasing operating equivalence ratio was found when tests were run with distillate fuel (%H = 13.0). However, when tests were run with residual fuel (%H = 11.4), the trend was reversed. In addition, when the same combustor was run with blends of distillate fuel and residual fuel, a drastic improvement of smoke was observed when only 6 percent of residual fuel was mixed with distillate fuel, and for any blending of more than 10 percent of residual fuel the combustor was practically smoke free. A chemical analysis of fuel samples revealed an appreciable amount of trace metals in the residual fuel, giving rise to the suspicion that the smoke reduction may have been due in part to these trace metals. Of these elements found, vanadium is believed to be the most likely to cause smoke reduction because of its relatively high concentration.

Time Between Overhaul vs Premature Removal Rates as Turbine Design Considerations

A general knowledge of aviation practices constituted the background for the identification of three distinct variables as the major drivers for engine removals in the operation of an aircraft. This study provides an insight into the interrelationships of the major drivers which determine engine removals for an aircraft: utilization rate (U), time between overhaul (TBO), and premature removal rate (PRR). Each of these elements is of concern to nearly every aircraft operator. For this study, it was assumed to be the same as aircraft flight hours per month.

An Analytical Study of Nitrogen Oxides and Carbon Monoxide Emissions in Hydrocarbon Combustion With Added Nitrogen: Preliminary Results

This work is one part of a four-part Critical Research and Technology Fuels Combustion Program funded by the Department of Energy. The primary objective of this part of the program is to analytically determine the effect of combustor operating conditions on the conversion of fuel-bound nitrogen (FBN) to nitrogen oxides (NOx). The effect of FBN and of operating conditions on carbon monoxide (CO) formation was also studied.

Fuel Character Effects on J79 and F101 Engine Combustor Emissions

Results of a program to determine the effects of fuel properties on the pollutant emissions of two US Air Force aircraft gas turbine engines are presented. Thirteen test fuels, including baseline JP-4 and JP-8, were evaluated in a cannular (J79) and a full annular (F101) combustor. The principal fuel variables were hydrogen content, aromatic structure, volatility, and distillation end point. Data analysis shows that fuel hydrogen content is a key fuel property, particularly with respect to high power emissions (oxides of nitrogen and smoke), and that low power emissions (carbon monoxide and hydrocarbons) are more dependent on fuel atomization and evaporation characteristics.

An Aerodynamic Method for Control and Range Improvement of Rotary Compressors

An aerodynamic method is proposed to replace the variable inlet guide vanes used for imparting compressor inlet prewhirl. High pressure jets are injected obliquely into the inflow, from orifices spaced around the periphery of the inlet pipe. A mathematical model of the flow situation was developed, which considers an unbounded axisymmetric jet ejected obliquely at various angles into a cross flow. The solution for the trajectory and growth of the jet was found to be in good agreement with relevant published experimental data. Prewhirl producing jet arrangements were designed and the flow deflection resulting from the combined action of the jets was measured for a range of jet velocities and cross flow velocities.

Atomizing Characteristics of Swirl Can Combustor Modules With Swirl Blast Fuel Injectors

Cold flow atomization tests of several different designs of swirl can combustor modules were conducted in a 7.6 cm diameter duct at airflow rates (per unit area) of 7.3 to 25.7 g/cm2 sec and water flow rates of 6.3 to 18.9 g/sec. The effect of air and water flow rates on the mean drop size of water sprays produced with the swirl blast fuel injectors were determined. Also, from these data it was possible to determine the effect of design modifications on the atomizing performance of various fuel injector and air swirler configurations. The trend in atomizing performance, as based on the mean drop size, was then compared with the trends in the production of nitrogen oxides obtained in combustion studies with the same swirl can combustors.

A User Programmable General Purpose Microprocessor Control System

This paper describes the hardware structure and design of a general-purpose microprocessor based controller intended for the full authority control of gas turbine and diesel engines in ground based vehicle and industrial applications. Particular attention is paid to the digital processor and how it’s design was influenced by the user requirements of a general purpose, real-time system. The system is currently being manufactured in production form. An accompanying paper describes the supporting software and user program facilities (Ref 1). Such systems based on the use of microprocessors must not only provide general purpose hardware, but also software structured so that a wide range of control algorithms may be programmed and performed within strict limits of real-time. This paper describes the development of the Type C4E87 General Purpose Controller (REF Fig. 1) with particular reference to its hardware structure and design within a system intended primarily for application as a full authority control of gas turbine and diesel engines etc.