Rotary Regenerator Research Articles

Discussion: “Predicted and Measured Pressure Drop in Parallel Plate Rotary Regenerators” (Maclain-Cross, I. L., and Ambrose, C. W., 1980, ASME J. Fluids Eng., 102, pp. 59–63)

Discussion: “Predicted and Measured Pressure Drop in Parallel Plate Rotary Regenerators” (Maclain-Cross, I. L., and Ambrose, C. W., 1980, ASME J. Fluids Eng., 102, pp. 59–63)

Closure to “Discussion of ‘Predicted and Measured Pressure Drop in Parallel Plate Rotary Regenerators’” (1980, ASME J. Fluids Eng., 102, pp. 253–254)

Closure to “Discussion of ‘Predicted and Measured Pressure Drop in Parallel Plate Rotary Regenerators’” (1980, ASME J. Fluids Eng., 102, pp. 253–254)

Predicted and Measured Pressure Drop in Parallel Plate Rotary Regenerators

The flow in the passages of parallel plate rotary heat exchangers or regenerators is laminar and fully developed. Laminar flow theory should allow an accurate prediction of heat and mass transfer and pressure drop. Previously measured values of pressure drop have been 20 percent higher than predicted. Pressure drop is predicted here by considering the passage cross section rectangular and correcting for flow acceleration, property variations, and inlet and outlet pressure drop. The pressure drops measured on a parallel plate sensible heat regenerator were within 3 percent of theory and on a prototype parallel plate total heat regenerator within 4 percent.

A Study of Chemical Reactivity in Ceramic Heat Exchangers

Past techniques to evaluate the resistance to chemical attack of rotary ceramic regenerator structures and materials have been used as screening tests with some success. The major drawback, though, has been the lack of simulation of the thermal and chemical characteristics of the exhaust stream. A new technique has been developed which allows one to reproduce more closely the environment of the regenerator and therefore determine the response of structures and materials to various chemical species and thermal gradients. Sulfur attack results from this test are compared with those from previous laboratory tests and also gas turbine engine tests. Materials considered include both β-spodumene and cordierite compositions. The essential conclusions from this study are: 1 – The SO2-gradient furnace can simulate the chemical and thermal environments of a rotary regenerator in operation; 2 – Sulfuric acid vapor ion-exchange is the predominant sulfur related reaction in β-spodumene rotary regenerators; 3 – Leaching of cordierite regenerators by sulfuric acid will not be observed unless the temperature on the cold face of the regenerator lies below the sulfuric acid dew point of the combustion gases.

Regeneration of Spent Granular Activated Carbon Used for Kraft Pulp Waste Treatment

Spent granular activated carbon, used for treating kraft pulping waste water, was regenerated. in an atmosphere of steam. Regenerating temperature and time were 620N9000C and 35. minutes respectively. The yield of regenerated activated carbon decreased with increasing temperature of rotary kiln regenerator and the same was true of its bulk density. But its strength decreased slightly.Adsorptive capacities of activated carbon, which was regenerated at high temperature, was superior to newly activated carbon.Studies on pore-size distribution based upon mercury prosimetry showed that the regeneration at high tempera re enlarged the pore-size. Consequently, adsorptive capacities for large melecules, e. g., molasseg. and kraft lignin, markedly increased. lnternal surface area of regenerated activated carbons was estimated by means of mercury porosimetry. lnternal surface area was closely correlated with molasses number.From the thermal analysis, it was found that regenerated activated carbon and newly activated one showed the same thermal property.

Glass-Ceramic Surfaces, Straight Triangular Passages—Heat Transfer and Flow Friction Characteristics

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 1300–2400 ft2/ft3, corresponding to a passage count of 526–2215 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. The present data are compared to previously available conflicting information and are recommended for design purposes, with stipulated specification relating to the uniformity of passages. Additionally, some limited information is provided relating to the low fouling characteristics of glass ceramic surfaces in the rotary regenerator application.

Paper 11: Regenerators for High Temperature Gas Turbine Engines

In various companies throughout the world a first generation of production vehicle gas turbine engines are being engineered. A vital component involved is the regenerative heat exchanger. The relative merits of the rotary regenerative and static recuperative heat exchanger are compared. Thermal efficiency and competitive initial cost are the two vital issues involved in the design of small gas turbines for the commercial establishment of gas turbine vehicles. The selection of a material for the rotary regenerator is essentially related to resolving the two vital issues of future small gas turbines and is, therefore, analysed. The account of the pioneering work involved in engineering the glass ceramic and other non-metal rotary regenerators includes a complete failure analysis based on running experience with over 200 ceramic regenerators. The problems of sealing, supporting and manufacturing the glass ceramic rotary generator are discussed and future practical regenerative designs are outlined. Heat exchange theory applied to small gas turbines is also reviewed.

Investigation of a rotary regenerator

The rotor drum 6 consists of two concentric shells; the space between them is baffled by radial ribs 7. The resulting compartment chambers are filled with packing 8 only partially down the length of the drum barrel. The unfilled portions act as channels to aid uniform distribution of the coolant over the front of the packings. The packing can be corrugated sheet metal, mesh, shot, or chips. The drum is mounted on a special flange 9 made of heat-insulating material(Textoli te, Teflonwith glass reinforced plastic filler, etc.). The flange features an extension machined to match the bearing 10, and gear toothing to drive the rotor shaft. The drum and flange are bolted together to form the shaftless overhung rotor of the regenerator. The shaftless rotor design makes it possible to minimize the amount of heat flowing in over the body of the drum (by reducing the area presented by the cross section}, while the overhung design and the heatinsulating flange set up favorable thermal conditions for the operation of the rotor bearings. In our case, the regeneratorbeari ngs function at room temperature, so that standard bearings can be used in the assembly. Sealing and gas distribution over the rotor packing in the low-pressure and high-pressure streams are achieved with the aid of packing plates in the fixed shaft-end seals. There are two of these shaft-end seals, one on the warm side, the other on the cold side of the rotor. The end plates have contoured ports allowing the high-pressure and low-pressure streams to pass through. These ports communicate with the

Thermal calculation of rotary regenerators with a dispersed packing

The integral Laplace transformation and the reduction of differential equations to Volterra integral equations are used to obtain a solution to the equation of the packing and gas temperature distribution over the thickness of the section of a rotary radially sectioned regenerator with a dispersed packing in relation to time for the initial period of operation of the regenerator.

Summary—Selected References on Gas Turbines, Regenerative Cycles, Rotary Regenerators, and Associated Heat-Exchange and Pressure-Drop Information

Summary—Selected References on Gas Turbines, Regenerative Cycles, Rotary Regenerators, and Associated Heat-Exchange and Pressure-Drop Information

Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines

Abstract An analysis of rotary-regenerator seal leakage is presented which predicts the leakage quantity and the variations of pressure gradient under the sealing shoe. The verifying results obtained from tests of a simulated sealing arrangement also are given. The optimum efficiency conditions of the gas-turbine cycle including leakage and pressure loss are studied; and a sample regenerator design for a specific gas-turbine plant is carried as far as the presentation of design-point curves for sizing the rotary regenerator. A method of reducing leakage is presented and the results of experimental verification are shown. Conclusions are drawn regarding the best general configuration of the rotary regenerator with respect to the leakage problem.

Discussion: “Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines” (Harper, D. B., 1957, Trans. ASME, 79, pp. 233–242)

Discussion: “Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines” (Harper, D. B., 1957, Trans. ASME, 79, pp. 233–242)

Discussion: “Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines” (Harper, D. B., 1957, Trans. ASME, 79, pp. 233–242)

Discussion: “Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines” (Harper, D. B., 1957, Trans. ASME, 79, pp. 233–242)

Discussion: “Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines” (Harper, D. B., 1957, Trans. ASME, 79, pp. 233–242)

Discussion: “Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines” (Harper, D. B., 1957, Trans. ASME, 79, pp. 233–242)

Closure to “Discussions of ‘Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines’” (1957, Trans. ASME, 79, pp. 242–244)

Closure to “Discussions of ‘Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines’” (1957, Trans. ASME, 79, pp. 242–244)

Discussion: “Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines” (Harper, D. B., 1957, Trans. ASME, 79, pp. 233–242)

Discussion: “Seal Leakage in the Rotary Regenerator and Its Effect on Rotary-Regenerator Design for Gas Turbines” (Harper, D. B., 1957, Trans. ASME, 79, pp. 233–242)

The Periodic-Flow Regenerator—A Summary of Design Theory

Abstract A description is given of the periodic-flow rotary regenerator, and it is contrasted to the other types of heat-exchanger systems which may be employed to “regenerate” or “recuperate” the exhaust-gas thermal energy in a gas-turbine plant. The advantages in principle of the periodic-flow type are considered briefly, and the mathematical complexities of analysis of the more exact theory of its performance are indicated. Available special solutions, obtained by numerical-graphical methods, provided by Hausen, Nusselt, Boestad, Iliffe, and Saunders and Smoleniec are reviewed and their limitations pointed out. An algebraic equation solution corresponding to the special case of high rotative speeds is shown to be exactly the same as the well-known equation for a direct-transfer-type counterflow exchanger. These results are supplemented with an “approximate theory” solution which has the advantage of being in closed form, and the limitations on accuracy of this solution are considered. Recommended design curves are presented using a set of simple nondimensional parameters, of the same nature as those employed for direct-transfer-type exchangers, and which are readily usable for the gas-turbine regenerator-design problem. The curves result from a rational extrapolation of the special case solutions of Hausen, employing the approximate theory as well as the results of Iliffe, to other situations of interest to the gas-turbine designer. An illustrative problem is included.