US1800730A - Rotor blade for high-temperature turbines - Google Patents

Rotor blade for high-temperature turbines Download PDF

Info

Publication number
US1800730A
US1800730A US434871A US43487130A US1800730A US 1800730 A US1800730 A US 1800730A US 434871 A US434871 A US 434871A US 43487130 A US43487130 A US 43487130A US 1800730 A US1800730 A US 1800730A
Authority
US
United States
Prior art keywords
blade
temperature
blades
strength
curve
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US434871A
Other languages
English (en)
Inventor
Holzwarth Hans
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
HOLZWARTH GAS TURBINE CO
Original Assignee
HOLZWARTH GAS TURBINE CO
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by HOLZWARTH GAS TURBINE CO filed Critical HOLZWARTH GAS TURBINE CO
Application granted granted Critical
Publication of US1800730A publication Critical patent/US1800730A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D5/00—Blades; Blade-carrying members; Heating, heat-insulating, cooling or antivibration means on the blades or the members
    • F01D5/12—Blades
    • F01D5/14—Form or construction
    • F01D5/141—Shape, i.e. outer, aerodynamic form

Definitions

  • the present invention relates to turbines operated by a driving medium of high temperature, such as explosion turbines, and has for one of its objects to provide blades for the rotors of such turbines which are of such form and construction as to be capable of being impinged for an indefinite period of time by jets of a driving medium of a temperature above the red heat of iron (about 550 (3.), and particularly by jets of explosion gases of high temperature, without failure or interruption of the normal operation of the turbine.
  • a driving medium of high temperature such as explosion turbines
  • Combustion gases transmit heat to the blades both by conduction and by radiation as they stream through the rotor blade channel, the degree of such heat transmission depending upon the temperature of the gases at any given point and also upon the temperature of the blades themselves at different points of their surface.
  • the heat so absorbed by each blade becomes distribthe blade reach.
  • My novel form of.blade is essentially different from the explosion turbine blades of the prior art and under the same conditions, such as equal operatin safety, similar blade material, similar com ustion gas temperature, pressure and velocity, the same number of jets per unit of time, the same number of combustion chambers, the same rotor diameter, and the same rotor speed, a considerable increase in the radial length of the blades and consequently a considerable increase in the capacity of the machine (which is an important advantage from the standpoint of the initial cost of a turbine plant), is made possible as compared with known blades; or, with the same radial length of blade, my invention makes possible an increase in the combustion gas temperature and consequently an increase in the thermal efficiency.
  • creeping strength is the most determining factor in building materials for blades which are exposed to high temperatures, and this property must receive the closest attention in the study of rotor blades.
  • creeping strength is meant the maximum load which can be continuously applied at a certain temperature for an indefinite period without causing a permanent distension of the material, at least not beyond a fixed safe maximum.
  • the creeping strength curve corresponding to the average temperature of the blade made of any suitable material, it will be found that this curve is convex to the abscissae axis and that its crown lies along the same abscissae as that in which is located the crown of the average temperature curve. Thedistance beteen this creeping strength curve and the curve representing the sum-of the loads-due to centrifugal force and the pressure of the gas stream, is then a measure of the strength of the blade against creeping.
  • a blade for explosion turbines is so constructed that the blade will resist the tendency to creep over indefinite periods of time.
  • the present invention thus embodies my discovery that because of the unavoidably high temperatures 1 which exist in the middle portion of the blade, the difference between the creeping strength and the actual load resulting from centrifugal force and gas pressure is so small in known blades that no suflicient reserve strength remains.
  • Fig. 4 represents a central longitudinal section ilarly represents a plan view of theconcave face of the blade developed as in Fig. 4; Fig. 6 is a development of the rear face of the blade; and Fig. 7 is a dia ramshowing the physical properties of a lade constructed.
  • Figs. 4, 5 and 6 are shown the isotherms which represent the temperatures at various points on and in the blade when the condition of equilibrium mentioned above, has been 'tively (Fig. 7).
  • the temperature conditions existing on the concave or trough surface of the blade are different from those upon the rear surface of the blade, while in the body of the blade there is a definite gradation from the temperatures at the concave surface to those at the convex or rear surface of the blade.
  • curve 7 is based on curve 4 for a definite blade material, such as, for example, an alloy containing 10% iron, 65% nickel, 15% chromium, and 7% molybdenum.
  • the blade according to Figs. 1-3 may therefore be loaded upto the amounts indicated by curve 5; actually its load is represented by the curve 1.
  • At about the middle safety is therefore'tobe found not at the foot of the blade, as was to be expected from prior art considerations, but at the horlzontal sec- 'reserve strength at thismiddle portion of the blade can be increased only to a very slight extent by known measures, and the means for increasing such reserve strength are not proportionate to the result.
  • the present invention embodies, however, the further discovery that I have made to the effect that the'sides of the blades, contrary to the hotter middle section, take on lower temperatures with increasing width and that finally the blade can be given a width at which the sides of the blade reach temperatures which lie considerably below that at which the creeping strength is exceeded.
  • the blade shown in Figs. 1 to 3 has been given a width of this degree as can be seen from Figs. 5 and 6.
  • a blade for the rotor of a turbine driven by a fluid of a temperature above the red heat of iron said blade capable of continuous operation for indefinite periods with the middle portion thereof at a temperature above red heat, the width of the blade being such that when the blade is in operation at rated or above rated capacity, sufficiently wide zones of lower temperature will surround the hotter central portion of the blade to reinforce the same. and prevent creeping of the blade.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Turbine Rotor Nozzle Sealing (AREA)
US434871A 1929-08-22 1930-03-11 Rotor blade for high-temperature turbines Expired - Lifetime US1800730A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE355028X 1929-08-22

Publications (1)

Publication Number Publication Date
US1800730A true US1800730A (en) 1931-04-14

Family

ID=6289852

Family Applications (1)

Application Number Title Priority Date Filing Date
US434871A Expired - Lifetime US1800730A (en) 1929-08-22 1930-03-11 Rotor blade for high-temperature turbines

Country Status (4)

Country Link
US (1) US1800730A (enrdf_load_stackoverflow)
BE (1) BE372479A (enrdf_load_stackoverflow)
FR (1) FR699920A (enrdf_load_stackoverflow)
GB (1) GB355028A (enrdf_load_stackoverflow)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2447896A (en) * 1946-02-01 1948-08-24 Armco Steel Corp High-temperature turbine
US2686654A (en) * 1948-10-19 1954-08-17 Thompson Prod Inc Coated member and method of making the same
US3041040A (en) * 1955-12-23 1962-06-26 Gen Electric Metal clad blade
US20090324419A1 (en) * 2006-07-25 2009-12-31 Luciano Cozza Highly corrosion-resistant movable blade assembly for a steam turbine, in particular a geothermal impulse turbine

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2447896A (en) * 1946-02-01 1948-08-24 Armco Steel Corp High-temperature turbine
US2686654A (en) * 1948-10-19 1954-08-17 Thompson Prod Inc Coated member and method of making the same
US3041040A (en) * 1955-12-23 1962-06-26 Gen Electric Metal clad blade
US20090324419A1 (en) * 2006-07-25 2009-12-31 Luciano Cozza Highly corrosion-resistant movable blade assembly for a steam turbine, in particular a geothermal impulse turbine

Also Published As

Publication number Publication date
FR699920A (fr) 1931-02-21
GB355028A (en) 1931-08-20
BE372479A (enrdf_load_stackoverflow) 1930-08-05

Similar Documents

Publication Publication Date Title
CA1276474C (en) Gas turbine drive with devices for branching off compressor air for cooling hot parts
US2552239A (en) Turbine rotor cooling arrangement
JPH08319803A (ja) 閉回路蒸気冷却動翼
US1800730A (en) Rotor blade for high-temperature turbines
DK153101B (da) Bremseskive med forbedret ventilationskoeling
US5151012A (en) Liquid cooled aerofoil blade
US3429557A (en) Steam turbine rotor cooling arrangement
Whitfield et al. Study of incidence loss models in radial and mixed-flow turbomachinery
US2451261A (en) High and low pressure turbine rotor cooling arrangement
SU411214A1 (enrdf_load_stackoverflow)
US20170009601A1 (en) Mechanical component for thermal turbo machinery
US2410259A (en) Elastic fluid mechanism
US2407531A (en) Elastic fluid mechanism
Chang et al. Experimental study of heat-transfer and pressure-drop performances of a rotating two-pass channel with composite stepped skew ribs and internal effusion
US2472886A (en) Turbine blade lashing
Emmert Current Design Practices for Gas-Turbine Power Elements
US1676946A (en) Centrifugal pump
US2462600A (en) Turbine
US3271004A (en) Turbine vane adapted for high temperature operation
US2963269A (en) Composite turbine buckets
US1156549A (en) Elastic-fluid turbine.
US2220914A (en) Elastic fluid turbine bucket wheel
US1972175A (en) Hydraulic infinitely variable speed transmission mechanism
US2699917A (en) Turbine wheel and blade construction
US1801427A (en) Gas-turbine blade