Accelerated Life Tests of a Pair of Naval Gas Turbines

This paper presents the results of a 2500-hr evaluation test performed at the U. S. Naval Engineering Experiment Station under the auspices of the Bureau of Ships. Test procedures, results, and conclusions are presented. The primary purpose of this test was to evaluate a compressor-turbine wheel with blades heavier than were in Fleet service at the time of test. This and other improvements have resulted in a forced downtime of 0.6 per cent over a thousand-hour period, and have shown justification for extension of the present 500-hr overhaul period to 1000 hr.

Nonsteady Aerodynamics of the Comprex Supercharger

A brief outline is given of the method of characteristics for the analysis of one-dimensional nonsteady flow. Two typical types of experiments are discussed which indicate the degree of accuracy possible if this method is applied to machinery like the Comprex supercharger. As an example, a typical analysis is presented for one particular engine-performance point. It is possible to duplicate engine test results with acceptable accuracy.

Valveless-Gas-Turbine Combustors With Pressure Gain

A valveless combustor has been developed which has been tested at one to three atmospheres of pressure. It discharged combustion products at practical turbine-inlet temperatures and at a total pressure above that of the inlet. Developmental problems encountered and results are discussed. The smooth combustor cycle, a phased system of combustor tubes and pulsation traps, achieves steady flow at the inlet and outlet of the combustor system to preserve the high efficiency of today’s turbines and compressors. The combustor will soon be tested on a gas-turbine compressor to verify efficiency gain estimates.

Design Analysis of the General Electric T58 Engine

The General Electric T58 is a lightweight, compact 1050 HP shaft powered gas turbine designed primarily for helicopters. Under sponsorship of the Navy Bureau of Aeronautics, this design was initiated with a development contract in June 1953.

Gas Turbines in the Arabian Desert

No men within 50 miles: But Tapline’s portable, radio-controlled, gas-turbine pumping units move oil across Saudi Arabia. The investment: One sixth that of a community-type station in that barren desert.

A Model W-121 Gas Turbine for Power Generation and Mechanical Drive

This paper presents the basic design of a Model W-121 gas turbine with a nominal rating of 12,000 hp and 8500 kw for mechanical and electrical drive applications. The over-all performance and efficiency are presented together with a description of the essential features of construction and design of the basic components.

Economic Considerations in Applying Gas Turbines to Electric Utility and Industrial Applications

Although there is tremendous interest in the gas turbine and it has become a fully recognized prime mover, there have been relatively little data collected in one paper which would aid in evaluating various gas turbine cycles. This paper presents estimating cost data which can be used for preliminary evaluations and discusses factors, unique with the gas turbine, which should be considered. Although well known, two of the common methods of evaluating power plants are discussed with particular reference to gas turbines.

Operating Experience With 750/1000-KW Gas Turbines

After giving a brief survey of some of the salient design features of the Mark TA 750/1000-kw gas turbine, an account is given of some of the different categories of application found for this machine on all six Continents of the World, indicating the economic factors which have led to the selection of gas turbines rather than alternative types of prime mover. The main portion of the paper deals with the operating experience which has been obtained on turbines burning natural gas, distillate, and crude oil fuels. The operation of twenty-nine Mark TA turbines which are now in service has been noteworthy for its complete freedom from blade breakages or other major failures. The few service troubles which have arisen, in nearly all cases, have been concerned with the operation of auxiliary equipment, and further development work is actively in progress on these items, in conjunction with the specialist manufacturers concerned, where necessary. The paper ends with an assessment of likely future trends in the application of medium-power gas turbines. Attention is given to the integration of the turbine with packaged assisted circulation boilers in order to provide compactness and flexibility of output.

Gas Turbines for Blast-Furnace Blowing

The steel-mill blast furnace consumes large quantities of coke, iron ore, limestone, and air. In addition to producing iron and slag, it also is a producer of large quantities of gas. For every ton of iron produced in the blast furnace, approximately 3 1/2 tons of air are consumed and 4 to 5 tons of blast-furnace gas are produced, which represents a calorific heat content equivalent to 9000 lb of steam at 450 psi and 750 F. Eighty per cent of this heat is available for the production of power and for blowing blast furnaces. This blast-furnace gas is of low btu content, ranging between 85 to 100 btu per cu.

The Effect of Treated High-Vanadium Fuel on Gas Turbine Load, Efficiency, and Life

Tests were run on four inter-cooled regenerative high-temperature gas turbines of like design to measure the effect of burning several different residual fuels. Some of the tests were made with the help and co-operation of the Central Vermont Public Service Corporation on two of their units at Rutland, Vermont. Other tests were made at Bangor, Maine, with the help and co-operation of The Esso Research and Engineering Company, and the Bangor Hydroelectric Company, on the two units in the Graham Station. The results of the tests can be summarized as follows: 1. After a few hundred hours of intermittent operation, the first-stage nozzle area reaches a steady-state condition wherein it oscillates between zero and a maximum of about 8 percent reduction in area due to oil ash. The maximum reduction varies from 4 percent to 8 percent, depending on the fuel; 2. With continuous operation the first-stage nozzle area does not reach a steady-state value in 100 hours but plugs more or less continuously at rates varying from 5 to 24 percent per hundred hours, depending on the fuel. The load decreases also at rates varying from one to twenty percent in the same period; 3. Increasing the magnesium content of the fuel with respect to its vanadium content increases the deposition rate, but increasing the aluminum with respect to the vanadium content has the opposite effect; 4. Substantial temperature changes due to load variations and changes of firing temperature have little or no effect on dislodging the ash, but shutdowns in excess of two hours duration cause recoveries of over 70 percent in the area and over 50 percent in the load; 5. Introducing about 15 pounds of spent refinery catalyst into the low-pressure compressor inlet results in more than 40 percent recovery in the nozzle area and about the same recovery in the load. This cleaning operation, followed by a shutdown, results in practically complete recovery in both load and area during subsequent operation. A test was run for 2400 hours with a single residual fuel containing about 360 ppm of vanadium following 2700 hours operation on distillate fuel. Comparisons of the gas-path parts with those of two other units of the same design, one using a residual oil having 80 ppm of vanadium and the other using natural gas, lead to the following conclusions: 1. The life of the gas-path parts is no different whether a high vanadium or a low vanadium residual fuel is used; 2. The corrosion of the nozzles and buckets is not much greater with treated residual oil than with natural gas.