Patent Application
20120009055
The present invention relates to a reaction-type turbine using steam, gas, or compressed air.
In general, a steam turbine is one of motorized devices to convert thermal energy from pressurized steam into mechanical motion. Due to low vibration, great efficiency, and high-speed and large-horsepower, the steam turbine has been widely used as a main engine for thermal power plants and ships.
The steam turbine injects high-temperature and high-pressurized steam produced by a boiler from nozzles or fixed blades, and expands the steam to generate a steam flow at high velocity. Then, the high-velocity steam flow is directed to strike turbine blades, which results in impact or reaction that drives a shaft to rotate.
Thus, the steam turbine may include a plurality of nozzles to convert thermal energy from steam into velocity energy and a plurality of turbine blades arranged in parallel to the nozzles to convert the velocity energy into mechanical motion.
In the conventional steam turbine, pressurized steam flowing into a steam chest from a boiler expands, rotates a turbine shaft coupled to the turbine blades as passing through the nozzles and the turbine blades, and then moves to an exhaust chest. The steam in the exhaust chest is sent to a condenser to be cooled, and then may be returned to the boiler by a feedwater pump or may be exhausted to atmosphere.
However, the conventional steam turbine as described above is characterized in generating rotation torque by a flow of a high velocity steam striking turbine blades that rotate at a high speed, and thus when condensate water is mixed with the steam, the turbine blades may be damaged. Hence, the steam flowing into the turbine blades is required to be managed, avoiding the condensate water being generated. Further, the turbine blades need to be manufactured with expensive materials, and assembling such turbine blades is complicated, thereby increasing the manufacturing cost.
A force to rotate the turbine axis is in proportion to momentum of steam entering the turbine blades, and the momentum of the steam is determined by various factors, such as the number and the surface area of the turbine blades and an inlet angle of the steam. However, since the steam striking the turbine blades changes velocity and direction, designing the shapes and angles of the blades in consideration of these changes increases design complexity, and thus there is a limitation in manufacturing a high-efficiency turbine.
Moreover, since a plurality of turbine blades rotate, enclosed by a housing, a space should be provided between an end of each turbine blade and an inner circumference of the housing in consideration of a thermal expansion of the turbine blade. However, steam is leaked through the space, and therefore a loss of pressure occurs, thereby deteriorating a thermal efficiency of the turbine.
The present invention is to solve the above-mentioned problems of the conventional steam turbine and provide a reaction-type steam turbine which can prevent component damage upon an impact by condensate water generated in steam and thus can facilitate the management of steam, allowing the use of low-cost materials and simplifying assembly process, which contributes to reduction of manufacturing costs.
Moreover, the present invention is to provide a reaction-type steam turbine which is a high-efficiency turbine obtained by reducing factors to determine the momentum from steam.
Further, the present invention is to provide a reaction-type steam turbine which has a thermal efficiency increased by reducing a loss of steam pressure
The present invention provides a reaction-type turbine including: a housing configured to include at least one injection casing; one or more jet and rotating units installed in the housing, each being configured to inject a fluid in a circumference direction and rotate by reaction to the injecting of the fluid; and a turbine shaft configured to rotatably coupled to the housing or coupled to rotate along with the housing and transmit rotary force to another device while rotating along with the jet and rotating units.
Additional features of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention.
According to the exemplary embodiments of the present invention, the reaction-type steam turbine is configured such that a jet and rotating unit and a turbine shaft rotate by the repulsive force generated when steam spurts from the jet and rotating unit, so as to generate propulsion force. Thus, the operating stability of a steam turbine can be maintained even when condensate water is mixed with the steam, and manufacturing costs can be significantly reduced. Further, in order to reduce a loss of energy, the flow resistance of the steam is remarkably reduced or pressure leakage is prevented, thereby obtaining a low-cost and high-efficiency turbine.
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention, and together with the description serve to explain the principles of the invention.
A reaction-type turbine is described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments of the invention are shown.
As shown in
The housing 110 includes a cylinder-shaped inlet 111, the injection casing 12, a guiding unit 113, and an outlet 114. The inlet 111 is provided with steam from a boiler (not illustrated), and the injection casing 112 expands to form a cylinder-shape, extending from the inlet 111. The guiding unit 113 extends to connect to the injection casing 112 and form a conical shape with top cut off, and the outlet 114 is a cylindrical shape extending to connect to the guide unit 113.
The inlet 111 may be formed concentrically to the outlet 114, and its outer circumference surface may be supported by a first bearing 141 in such a manner that allows the steam turbine to rotate. The inlet 111 may be formed to penetrate through one side of the injection casing 112. In this case, an extension portion (not illustrated), which extends from the first jet and rotating unit 120A in such a manner that penetrates through the inlet 111 and is hermetically coupled to the inlet 111, may be supported by the first bearing 141.
An inner circumference of the injection casing 112 may be formed in a shape of a smooth tube, and a steam guiding unit may be formed in a forward direction with respect to a rotation direction of the jet and rotating units 120A, 120B, and 120C to guide the moving of the steam injected from the third jet and rotating unit 120C. The steam guiding unit may be formed as grooves 112a which are arranged at regular intervals along a circumference direction of the injection casing 112 as shown in
The guiding unit 113 may have a tilted inner circumference surface such that a diameter of the guiding unit 113 decreases from the injection casing 112 to the outlet 114, thereby smoothly guiding the steam passing through the injection casing 112 to the outlet 114. The guiding unit 113 may be vertically formed, having a rounded or sloped contacting portion that meets the outlet 114.
The outlet 114 may be formed as a cylindrical shape as shown in
The first, the second, and the third jet and rotating units 120A, 120B, and 120C, respectively, include chambers (hereinafter, referred to as a first chamber 121, a second chamber 122, and a third chamber 123 from innermost to outermost) and sets of a plurality of injecting passages (hereinafter, referred to as a set of first injecting passages 124, a set of second injecting passages 125, and a set of third injecting passages 126 from innermost to outermost). Each of the first, the second, and the third chambers 121, 122, and 123 is formed as a hollow cylindrical shape with closed ends in a shaft direction, and the first, the second, and the third chambers 121, 122, and 123 are disposed in a manner to radially expand in size. The first, the second, and the third injecting passages are formed on the outer circumferences of the respective chambers 121, 122, and 123 along a circumference direction, such that steam can be consecutively injected from an inner space S1 of the first chamber 121 to an inner space S2 of the second chamber 122, from the inner space S2 of the second chamber 122 to an inner space S3 of the third chamber 123, and from the inner space S3 of the third chamber 123 to the injecting room 112 in a circumference direction.
The first, the second, and the third chambers 121, 122, and 123 have the inner spaces S1, S2, and S3 of the same volume, as shown in
The first, the second, and the third chambers 121, 122, and 123 may have the inner spaces S1, S2, and S3 of different volumes. For example, the size of each of the inner spaces S1, S2, and S3 of the respective chambers 121, 122, and 123 may increase or decrease in proportion to the whole cross-sectional area of each of the respective jet passages 124, 125, and 126.
The first, the second, and the third jet passages 124, 125, and 126 may be provided as a set of jet passages of a circular shape being arranged at regular intervals from one another on the respective chambers 121, 122, and 123 in a shaft direction as shown in
As shown in
Furthermore, a net cross-sectional area of all jet passages on the respective chambers 121, 122, and 123 may be adjusted by differentiating the cross-sectional area of the jet passages of each of the chambers 121, 122, and 123, or by differentiating the numbers of the jet passages among the chambers 121, 122, and 123. For example, as shown in
The jet passages 124, 125, and 126 may have different shapes. For example, as shown in
The turbine shaft 130 penetrates through the center of the housing 110 and the jet and rotating units 120A, 120B, and 120C and is welded to the chambers 121, 122, and 123 of the respective jet and rotating units 120A, 120B, and 120C. In addition, one end of the turbine shaft 130 may be rotatably supported by a second bearing 142 such that the whole steam turbine including the turbine shaft 130 can rotate. In this case, the turbine shaft 130 is designed to have a smaller diameter than that of the inlet 111 or the outlet of the housing 110 in order to allow steam to flow outside of the turbine shaft 130.
The reaction-type steam turbine according to the exemplary embodiment of the present invention operates as described below.
When steam produced from the boiler is provided to the inlet 111 of the housing 110 through a pipe, the steam flows into the first chamber 121 of the first jet and rotating unit 120A, and the steam in the first chamber 121 is injected in a circumference direction through the first jet passages 124 and thereby flows into the second chamber 122 of the second jet and rotating unit 120B. Additionally, the steam is injected in the circumference direction through the second jet passages 125 and flows into the third chamber 123 of the third jet and rotating unit 120C. Then, the steam in the third chamber 123 is injected in the circumference direction to the injection casing 112 through the third jet passages 126, and the steam in the injecting casing 112 is exhausted to atmosphere through the guiding unit 113 and the outlet 114 or is collected in a condenser (not illustrated) to be returned to the boiler, and these procedures are repetitively performed. A pressure of the steam decreases stepwise while passing through the jet and rotating units 120A, 120B, and 120C, and the steam turbine thus can obtain effective jet velocity.
As described above, the jet and rotating units rotate by the propulsion force generated from the reaction force produced as the steam is injected in a circumference direction through the jet passages of the respective jet and rotating units, and accordingly the turbine shaft coupled to the jet and rotating units obtains rotary motion and is thereby rotated and can transmit the rotary force to an external device.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.
According to the first exemplary embodiment, the turbine shaft 130 penetrates through the housing 110 and has one side supported by the first bearing 141 while one side of the housing 110 is supported by the second bearing 142, whereas according to the second exemplary embodiment, as shown in
In this case, one end of the turbine shaft 130 may be supported by the first bearing 141 at an outer edge of the outlet 114, or in some cases, may be supported by the first bearing 141 between the turbine shaft 130 and the outlet 114 of the housing 110. Here, if the first bearing 141 is disposed at the outer edge of the outlet 114, the outlet 114 is formed as a cylindrical shape. On the other hand, if the first bearing 141 is interposed between the turbine shaft 130 and the outlet 114, the outlet 114 may have a plurality of ribs 114a formed radially thereon so as to effectively discharge the steam. In addition, the other end of the turbine shaft 130 may be supported by the second bearing 142 at an outer edge of the inlet 11 of the housing 110, and in some cases, may be supported by the second bearing 142 interposed between the turbine shaft 130 and the inlet 111 of the housing 110. In this case, if the second bearing 142 is disposed at the outer edge of the inlet 111, the inlet 111 is formed as a cylindrical shape, and if the second bearing 142 is interposed between the turbine shaft 130 and the inlet 111, the inlet 111 may have a plurality of ribs 111a formed radially thereon so as to allow the steam to effectively flow into the first jet and rotating unit 120A.
Other configurations and effects of the second exemplary embodiment are significantly the same as those of the first exemplary embodiment, and thus a detailed description thereof will not be reiterated. However, the steam turbine according to the second exemplary embodiment is configured such that the housing 110 and each of the jet and rotating units 120A, 120B, and 120C can be slidably in contact with each other, as shown in
In the first and second exemplary embodiments as described above, the turbine shaft 130 penetrates through the housing 110 and is supported by the first bearing 141, while in the third exemplary embodiment, one end of the turbine shaft 130 is welded to the third jet and rotating unit 120C inside the housing 110, and the other end of the turbine shaft 130 is rotatably supported by the first bearing 141, as illustrated in
Other configurations and effects of the third exemplary embodiment are similar to those of the first and second exemplary embodiments as described above, and accordingly a detailed description thereof will be omitted. In the steam turbine according to the third exemplary embodiment, as illustrated in
In the first, the second, and the third exemplary embodiments as described above, the turbine shaft 130 provided separately from the housing 110 is coupled with the housing 110 in a manner to penetrate through the housing 110, while in the fourth exemplary embodiment, the turbine shaft 130 is integrated with the housing 110, as illustrated in
Other configurations and effects of the fourth exemplary embodiment are similar to those of the first through third exemplary embodiments as described above, and accordingly a detailed description will be omitted. Since the steam turbine according to the fourth exemplary embodiment requires no turbine shaft, as illustrated in
In the first through fourth exemplary embodiments as described above, the first, the second, the third jet and rotating units 120A, 120B, and 120C are arranged radially in a manner to be placed one upon another in one housing 110, while in the fifth exemplary embodiment, a plurality of housings and a plurality of jet and rotating units are disposed at regular intervals in the shaft direction.
For example, in the steam turbine according to the fifth exemplary embodiment, as illustrated in
The first, the second, and the third housings 210, 220, and 230 respectively have guiding units 213, 223, and 233 whose inner circumference surfaces are respectively tilted toward the jet and rotating units 250 and 260 and the outlet 234 (will be described later), in one sides of the respective injection rooms 212, 222, and 232.
The guiding units 213, 223, and 233 smoothly guide the steam passing through the injection rooms 212, 222, and 232 to the chambers 251 and 261 of the jet and rotating units 250 and 260 or to the outside. The first, the second, and the third housings 210, 220, and 230 may be formed in a shape of a tube whose inner walls are smooth. Or, the inner walls of the first, the second, and the third housings 210, 220, and 230 may have a plurality of steam guiding units which are grooves 215, 225, and 235 or blades 216, 226, and 236 that are arranged in a forward direction with respect to a rotation direction of the jet and rotating units 240, 250, and 260, in order to smoothly guide the moving of the steam spurted from the jet and rotating units 240, 250, and 260.
The chambers 241, 251, and 261 of the first, the second, and the third jet and rotating units 240, 250, and 260 may have the same volume or different volumes. The volume of each of the chambers 241, 251, and 261 may increase or decrease in proportion to a net cross-sectional area of injection passages 242, 252, and 262 included in the respective chambers 241, 251, and 261. For example, as illustrated in
Furthermore, the whole cross-sectional areas of the injection passages 241, 251, and 261 may be adjusted by differentiating the cross-sectional areas of the individual injection passages 241, 251, and 261, or by differentiating the numbers of the injection passages 241, 251, and 261. For example, as illustrated in
Other configurations and effects of the fifth exemplary embodiment are similar to those of the first through fourth exemplary embodiment, and accordingly a detailed description thereof will be omitted.
Therefore, since the reaction-type steam turbine as described above acquires propulsion force by the repulsive force generated when steam from a boiler spurts from the jet and rotating units through the injection passages, the reaction-type steam turbine is free from component damage upon an impact by condensate water mixed in the steam. Thus, the operating stability of the steam turbine can be remarkably improved and component damage can be prevented, allowing the use of low-cost materials. Furthermore, assembly process is simplified, which leads to a significant reduction of manufacturing costs. For example, a conventional impeller-type turbine has required a precise design and fabrication of hundreds or thousands of impellers, as well as complicated assembly process, which needs high-quality human resources and precision, while the reaction-type turbine as described above obtains high efficiency with significantly low precision requirements upon the designing, fabrication or assembly of components. Accordingly, the reactive-type turbine can be manufactured with remarkably low costs compared to the conventional impeller-type turbine.
Moreover, since a plurality of jet and rotating units are arranged radially for stability improvement of the steam turbine, the size of the steam turbine can be reduced, and no flow resistance of the steam is generated between the jet and rotating units, resulting in efficiency improvement of the steam turbine and relative efficiency improvement of a boiler. In the case where the jet and rotating units are arranged in a direction of a shaft, tilted guiding units are formed in the housing to reduce the flow resistance of the steam, thereby enhancing the efficiency of the steam turbine and the relative efficiency of the boiler.
Furthermore, the steam turbine, which utilizes the Law of Action and Reaction which is Newton's third law of motion, can reduce energy consumption for generating propulsion force in the steam turbine, like the impeller-type turbine (or a momentum transfer-type turbine), thus obtaining high efficiency.
If the pressure of steam from a boiler is constant and the velocity of steam spurted from the jet and rotating units is equal to circumferential speed by rotation of the jet and rotating units, the steam is stopped with respect to the jet and rotating units and only the jet and rotating units move in the opposite direction of a tangential line at the injection velocity of the steam, so that a theoretical energy transfer ratio of the entire momentum or kinetic energy of the steam reaches 100%. Accordingly, the steam turbine can obtain high efficiency that could have never been achieved by any impeller-type turbines.
It will be apparent to those skilled in the art that various modifications and variation can be made in the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.
The present invention can be efficiently applied to a gas turbine and an engine making use of pressed air as well as the above-described steam turbine.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/KR09/01389 | 3/18/2009 | WO | 00 | 9/16/2011 |
