Showing papers in "Journal of Engineering for Power in 1970"
305 citations
218 citations
TL;DR: Rotor wakes intrastator transport effects on high Mach number axial flow compressors performance, considering stagnation temperature profile and rotor blade loss factor, were investigated in this article, where they showed that rotor wake intrastation transport effects had a significant impact on axial Flow Compressor performance.
Abstract: Rotor wakes intrastator transport effects on high Mach number axial flow compressors performance, considering stagnation temperature profile and rotor blade loss factor
193 citations
TL;DR: In this paper, the interactions between thermodynamics and economics for complex systems in a manner which assures a wise use of non-renewable energy resources are formulated in a way which assures the use of renewable energy resources.
Abstract: This paper formulates the interactions between thermodynamics and economics for complex systems in a manner which assures a wise use of nonrenewable energy resources. The concept of “essergy” (generalized potential work) is used to reduce all thermodynamic processes to a common basis of evaluation and comparison. The concept of “internal economy” is used as a means of estimating the economic value of essergy, thus permitting a designer to trade essergy dissipation against capital expenditure in the main dissipative zones of a thermodynamic system. This approach extends the classical optimization problem of balancing running expenses against fixed charges of single-zone, single-degree-of-freedom systems to stagewise as well as interconnected multi-zone multidegrees-of-freedom systems. A companion paper discusses some detailed applications.
147 citations
TL;DR: In this article, an experimental study of an air-cooled gas turbine disk using the model of a disk rotating near a shrouded stator is presented. Measurements of pressure distribution, frictional moment, and cooling air flow necessary to prevent the ingress of hot gases over the turbine disk are described for a range of rotational speeds, mass flow rates, and different geometries.
Abstract: This paper describes an experimental study of an air-cooled gas turbine disk using the model of a disk rotating near a shrouded stator. Measurements of pressure distribution, frictional moment, and the cooling air flow necessary to prevent the ingress of hot gases over the turbine disk are described for a range of rotational speeds, mass flow rates, and different geometries. The pressure distribution is shown to be calculable by the superposition of the pressure drop due to the shroud and the unshrouded distribution. Moment coefficients are shown to increase with increasing mass flow rate and decreasing shroud clearance, but are little affected by the rotor/stator gap. Applying Reynolds analogy to the moment coefficients, it is estimated that heat transfer from the rotor will be controlled primarily by rate of radial cooling flow at low rotational Reynolds numbers, and will be governed primarily by Reynolds number at large rotational speeds.
118 citations
TL;DR: In this paper, it was shown that manufacturing tolerances of several thousandths of an in. in passage dimension have a significant influence on the overall heat transfer and flow friction behavior.
Abstract: Several current designs for high effectiveness gas turbine regenerators involve low Reynolds number fully developed, laminar flow type surfaces. Such surfaces consist of cylindrical flow passages, of small hydraulic radius, in parallel. The cylinder geometry may, as examples, be triangular, as in some glass-ceramic surfaces, or rectangular, as in deepfold metal foil surfaces. This presentation demonstrates that manufacturing tolerances of several thousandths of an in. in passage dimension have a significant influence on the overall heat transfer and flow friction behavior. The analysis is also useful in rationalizing the difference between theory and test results for the basic heat transfer (j factor) and friction (f factor) characteristics as a function of Reynolds number for various surfaces of the laminar flow type.
30 citations
27 citations
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19 citations
TL;DR: In this paper, two approaches to avoid cracking in graphite-epoxy composites were presented to avoid the cracking during fabrication, based on the transverse tensile strength of the unidirectional composite layers and the stress developed during fabrication.
Abstract: Residual thermal stresses are present in cross-plied graphite-epoxy composites due to the anisotropic thermal and mechanical properties of the individual layers. Experimental measurements and analytical calculations of the thermal stress induced in two different cross-plied composites during fabrication are presented and shown to be in good agreement. The occurrence of cracking in certain composites is explained in terms of the transverse tensile strength of the unidirectional composite layers and the stress developed during fabrication. Two approaches are presented to avoid cracking during fabrication.
TL;DR: In this paper, a program of experimental and analytical research designed to evaluate the aerodynamic and thermodynamic performance of transpiration-cooled porous surfaces in the high-temperature gas turbine was described.
Abstract: This paper describes a program of experimental and analytical research designed to evaluate the aerodynamic and thermodynamic performance of transpiration-cooled porous surfaces in the high-temperature gas turbine. The aerodynamic penalties of effusing coolant through a set of nozzle blades are shown to be small, particularly when compared with the thermodynamic advantages which accrue from the effective cooling obtained. Although the effusing coolant can in certain circumstances increase gas to blade heat transfer rates by destabilizing a laminar boundary layer, in the turbulent boundary layers which predominate in turbine practice there is inevitably a reduction in heat transfer which can be satisfactorily predicted theoretically. In the combustion system of the gas turbine, transpiration cooling appears also to be very attractive, but much work remains to be done on heat transfer rates in the flame-tube.
TL;DR: In this paper, an investigation was made of the reaction between SO2 and limestone and dolomite particles in flue gas, and the initial reaction products are sulfites, and as the particle temperature rises above about 1400 deg F, SO2 is lost by thermal decomposition of the sulfite.
Abstract: An investigation was made of the reaction between SO2 and limestone and dolomite particles in flue gas. Reaction data were generated by exposing the particles to flue gas in a dispersed-phase reactor that simulates localized boiler-furnace conditions. Variables included in the study were residence time, temperature, particle size, SO2 concentration, and chemical state of the stone. A model is hypothesized for the SO2 - particle reaction that is consistent with the experimental data. The hypothesis states that the initial reaction products are sulfites, and that as the particle temperature rises above about 1400 deg F, SO2 is lost by thermal decomposition of the sulfite. Concurrently the sulfite can oxidize and/or disproportionate to form sulfate.
TL;DR: In this paper, basic heat transfer and flow friction design data are presented for three straight, triangular passage, glass-ceramic heat exchanger surfaces, with heat transfer area density ratios ranging from 1300 to 2400 feet square/foot cubed, corresponding to a passage count of 526 to 2215 passages per sq. in.
Abstract: : Basic heat transfer and flow friction design data are presented for three straight, triangular passage, glass-ceramic heat exchanger surfaces. These surfaces have heat transfer area density ratios ranging from 1300 to 2400 foot square/foot cubed, corresponding to a passage count of 526 to 2215 passages per sq. in. Glass-ceramic heat exchangers are of importance to vehicular gas turbine technology as they give promise of allowing low mass production costs for the high effectiveness rotary regenerator required in most of the vehicular turbine engine concepts now under development. (Author)
TL;DR: In this paper, an incompressible, two-dimensional, potential flow analysis for thick, highly cambered multibodies in cascade is presented and extended to include compressibility.
Abstract: The performance of axial flow compressors can be improved when it becomes possible to achieve higher loading per stage than currently attainable. The major obstacles to attaining this objective are the limitations on loading in the end wall region and the limited range of operating incidence of compressor blades. A possible method of achieving a wide range of operating incidence is the use of slotted or multibody airfoils. An incompressible, two-dimensional, potential flow analysis for thick, highly cambered multibodies in cascade is presented. The analysis is extended to include compressibility. A boundary-layer calculation, including a wake model, is described and used to predict cascade losses. Theoretical predictions are compared against slotted and unslotted cascade and compressor stator experimental results and adequate agreement obtained. The slotted blade concept is shown to offer performance benefits, provided that end-wall loading limitations can be overcome.
TL;DR: Turbine blade designs considered for increasing load capacity covering tandem, jet-blade and base plain blade configurations and test results were presented in this article, where the authors considered a variety of blade configurations.
Abstract: Turbine blade designs considered for increasing load capacity covering tandem, jet-blade and base plain blade configurations and test results
TL;DR: In this paper, two-dimensional cascade results were obtained in transonic and supersonic cascade windtunnels, which were analyzed with the aid of a simple calculation, which showed that the axial velocity-density ratio has to be considered as an important parameter.
Abstract: : The paper presents two-dimensional cascade results which were obtained in transonic and supersonic cascade windtunnels. The upstream Mach number range is 1.0 < or = M < or = 1.4. Tests were carried out with three different blade shapes; these are double-circular-arc and wedge profiles. The influence of solidity on the performance of these cascades was investigated. A detailed analysis and calculation of the shock losses shows the great influence of profile shape on the total pressure loss coefficient. The profile losses are roughly constant in the investigated Mach number range. In addition, some measurements for different back pressures are presented. These results are analyzed with the aid of a simple calculation, which shows that the axial velocity-density ratio has to be considered as an important parameter in supersonic cascade measurements. (Author)
TL;DR: In this paper, the empirical expression Nu = 0.643 (GrSc)0.25 developed for the evaporation of water was used to predict sodium vapor deposition in LMFBRs.
Abstract: Sodium vapor deposition is acknowledged to be a potential problem in several activities associated with Liquid Metal Fast Breeder Reactors (LMFBRs). Attempts were made to predict sodium evaporation rates using the empirical expression Nu = 0.643 (GrSc)0.25 developed for the evaporation of water. Small scale experiments were performed which indicate the general validity of this expression for sodium evaporation. The experiments also demonstrated that deposition of sodium within inert gas filled enclosures can be substantially reduced by circulating and filtering the atmosphere of the enclosure.
TL;DR: In this article, an experimental method for measuring the temperature of luminous flames with a two-color pyrometer and radiant intensity by means of a total radiation pyrometers is described.
Abstract: The radiation heat load assumes an important role in gas turbine life and performance as firing temperatures and pressures are increased. This first phase of a program for assessing radiant heat loading was mainly concerned with devising measurement techniques. An experimental method for measuring the temperature of luminous flames with a two-color pyrometer and radiant intensity by means of a total radiation pyrometer is described. Emittance data from two combustion liner configurations is included for chamber pressures of from 2 to 7.5 atmospheres over the turbine inlet temperature range of 900 to 1950 deg F.