JP2013189915A - Turbo pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a turbo pump that can cool a bearing while reducing the bearing loss.SOLUTION: A turbo pump includes a main shaft 1 that is rotated by turbine blades in a casing 2; a bearing 4 that includes a bearing inner ring 42 connected with the main shaft 1, a bearing outer ring 43 connected with the casing 2, and a rolling element 41 rotationally moving between the bearing inner ring 42 and the bearing outer ring 43; and a bearing cooling mechanism. The bearing cooling mechanism includes an orifice 22 and a guide vane 31. The orifice 22 is a fluid restricting mechanism and generates a jet flow c1 in which fluid pressurized by the impeller 10 rotating in conjunction with the main shaft 1 is jetted out. The guide vane 31 is a fluid flow straightening part, straightens the jet flow c1 by controlling it so as to increase velocity components in the rotation direction (the revolution direction B) of the main shaft 1, and cools the rolling elements 41.

Description

  The present invention relates to a turbo pump for cooling a bearing.

  Patent Document 1 describes a turbo pump in which liquid flowing into a bearing is used for lubrication and cooling of the bearing.

JP 2007-085223 A

  In the turbo pump described in Patent Document 1, the liquid that has flowed into the bearing is pushed by the rolling elements of the bearing and undergoes rotational motion. And the energy which a rolling element acts on a liquid becomes resistance with respect to rotation of the main shaft of a turbo pump. For this reason, in a turbo pump that requires cooling of the bearing, it is required to reduce the loss of the bearing.

  The present invention solves the above-described problems, and an object thereof is to provide a turbo pump capable of cooling a bearing while reducing the loss of the bearing.

  In order to achieve the above object, a turbo pump includes a main shaft that is rotated by turbine blades in a casing, a bearing inner ring that is connected to the main shaft, a bearing outer ring that is connected to the casing, and the bearing inner ring and the bearing outer ring. A rolling element that rotationally moves the fluid, a fluid throttle mechanism that generates a jet that ejects fluid pressurized by an impeller that rotates in conjunction with the main shaft, and the same direction as the rotational direction of the main shaft A bearing cooling mechanism including a fluid rectifying unit that regulates and rectifies the flow of the jet so as to increase a speed component in a circumferential direction of the rolling element that rolls.

  With this configuration, the fluid rectifying unit can reduce a loss of rolling in the circumferential direction of the rolling element. And a jet can assist the motion of the rolling direction of the rolling element to roll. As a result, the energy that the rolling elements act on the liquid can be reduced, and the resistance against rotation of the main shaft of the turbo pump can be suppressed. For this reason, the turbo pump can cool the bearing while reducing the loss of the bearing.

  As a desirable aspect of the present invention, it is preferable that the fluid rectifier does not rotate in conjunction with the main shaft.

  With this configuration, the fluid rectifying unit can create a jet flow having a velocity component equal to or higher than the speed of the rolling element in the circumferential direction of the rolling element that rolls in the same direction as the rotation direction of the main shaft. And a jet can assist the motion of the rolling direction of the rolling element to roll.

  As a desirable aspect of the present invention, it is preferable that the fluid rectifying unit is integrated with the fluid throttle mechanism to regulate a jet direction.

  With this configuration, the fluid throttle mechanism can create a jet flow having a speed component equal to or higher than the speed of the rolling element in the circumferential direction of the rolling element that rolls in the same direction as the rotation direction of the main shaft. And a jet can assist the motion of the rolling direction of the rolling element to roll.

  As a desirable aspect of the present invention, it is preferable that the fluid rectifying unit is a moving blade that rotates in conjunction with the main shaft.

  With this configuration, the energy of the jet can be recovered as the rotation of the main shaft in the circumferential direction. Thereby, the temperature of a jet flow falls and a cavitation margin can be widened. Further, the fluid rectification unit rectifies the jet while rotating in conjunction with the main shaft. For this reason, the fluid rectification unit can create a jet flow having a velocity component equal to or higher than the speed of the rolling element in the circumferential direction of the rolling element that rolls in the same direction as the rotation direction of the main shaft.

  ADVANTAGE OF THE INVENTION According to this invention, the turbo pump which can cool a bearing, reducing the loss of a bearing can be provided.

FIG. 1 is a schematic piping system diagram of a rocket engine to which a turbo pump according to an embodiment is applied. FIG. 2 is a schematic configuration diagram of the turbo pump according to the present embodiment. FIG. 3 is a schematic partial cross-sectional view illustrating the pump of the turbo pump according to the first embodiment. FIG. 4 is an explanatory diagram for explaining a bearing cooling mechanism of the turbo pump according to the first embodiment. FIG. 5 is an explanatory diagram for explaining a bearing cooling mechanism of the turbo pump according to the second embodiment. FIG. 6 is a schematic partial sectional view showing a pump of the turbo pump according to the third embodiment. FIG. 7 is an explanatory diagram for explaining a bearing cooling mechanism of the turbo pump according to the third embodiment.

  DESCRIPTION OF EMBODIMENTS Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements described below can be appropriately combined.

(Embodiment 1)
FIG. 1 is a schematic piping system diagram of a rocket engine to which a turbo pump according to an embodiment is applied. The rocket engine 100 uses part of the fuel as a coolant for the rocket combustor 101 and also as a drive medium for the turbo pump 50 and the turbo pump 60 that pressurize and pump the oxidant and fuel.

<Rocket engine>
The rocket engine 100 includes an injector 102 that can inject oxidant and fuel, and includes a rocket combustor 101 that can combust oxidant and fuel. Furthermore, the rocket engine 100 supplies a fuel supply line 90 for supplying fuel to the rocket combustor 101 as a piping system for supplying the oxidant and fuel to the rocket combustor 101 and circulating the oxidant and fuel to each part of the rocket engine 100; An oxidant supply line 91 for supplying an oxidant to the rocket combustor 101; a cooling medium / turbo pump drive medium supply line 92 for circulating fuel to each part of the rocket engine 100 as a cooling medium for cooling the rocket combustor 101; Is provided.

The fuel supply line 90 is composed of a plurality of pipes, and connects a fuel tank that stores liquid hydrogen as fuel (hereinafter referred to as “LH ₂ ”) and the injector 102 of the rocket combustor 101, to Configure the supply system. Similarly, the oxidant supply line 91 includes a plurality of pipes, and an oxidant tank that stores liquid oxygen (hereinafter referred to as “LOx”) as an oxidant, and the injector 102 of the rocket combustor 101. Are connected to form an oxidant supply system. The cooling medium / turbo pump drive medium supply line 92 includes a plurality of pipes, branches from the fuel supply line 90 at one end, and passes through a cooling passage 105 in the wall surface of the combustion chamber 103 in the rocket combustor 101 described later. The other end is connected to the inside of the nozzle 104 of the rocket combustor 101 to constitute a cooling medium / driving medium supply system.

  The rocket engine 100 can pump the oxidant to the rocket combustor 101 via the fuel turbo pump 50 and the oxidant supply line 91 that can pump the fuel to the rocket combustor 101 via the fuel supply line 90. It includes an oxidant turbo pump 60, a mixer 70 that mixes fuel vaporized by cooling the rocket combustor 101 and liquid fuel, and an igniter 80 that ignites the mixture of oxidant and fuel.

The fuel turbo pump 50 includes a pump 51 and a turbine 52. The turbine 52 is driven to rotate by hydrogen gas (hereinafter referred to as “GH ₂ ”) as fuel that has passed through the cooling passage 105 and is vaporized, thereby driving the pump 51. LH ₂ is pressurized and fed to the injector 102. The oxidant turbo pump 60 includes a pump 61 and a turbine 62. The turbine 62 is driven to rotate by GH ₂ as vaporized fuel that has passed through the cooling passage 105 to drive the pump 61, and the pump 61 pressurizes LOx of the oxidant supply line 91 and pumps it to the injector 102. To do.

Fuel supply line 90 includes, in order from the upstream side relative to the flow direction of the LH _2, it comprises a pump 51 of the turbo pump 50 for fuel, the main fuel valve 93, and a mixer 70. The oxidant supply line 91 includes a pump 61 of a turbo pump 60 for oxidant and a main oxidant valve 94 in order from the upstream side with respect to the flow direction of LOx.

The cooling medium / turbo pump drive medium supply line 92 branches from the fuel supply line 90 on the downstream side of the pump 51 and the upstream side of the main fuel valve 93 with respect to the flow direction of LH ₂ in the fuel supply line 90. The cooling medium / turbo pump drive medium supply line 92 is, in order from the upstream side with respect to the flow direction of LH _{2 in} the fuel supply line 90, the combustion chamber cooling valve 92c, the cooling passage 105, the thrust control valve 95, and the fuel The turbine 52 of the turbo pump 50 and the turbine 62 of the oxidant turbo pump 60 are provided.

  The turbine 52 of the turbo pump 50 for fuel and the turbine 62 of the turbo pump 60 for oxidant are arranged in series in the cooling medium / turbo pump drive medium supply line 92. The cooling medium / turbo pump driving medium supply line 92 also includes a cooling passage for cooling the nozzle 104 on the upstream side of the portion connected to the inside of the nozzle 104 at the other end. The specific configurations of the fuel turbo pump 50 and the oxidant turbo pump 60 will be described later.

  The cooling medium / turbo pump drive medium supply line 92 includes a merging pipe 96, a mixing ratio control pipe 97, and a bypass pipe 98. The merge pipe 96 branches from the main pipe of the cooling medium / turbo pump drive medium supply line 92 on the downstream side of the cooling passage 105 and the upstream side of the thrust control valve 95 and is connected to the mixer 70. The mixing ratio control pipe 97 is branched from the main pipe of the cooling medium / turbo pump drive medium supply line 92 on the upstream side of the turbine 62 of the turbo pump 60 for oxidant and on the downstream side of the turbine 52 of the turbo pump 50 for fuel. By connecting to the downstream side of the turbine 62, the turbine 62 is bypassed. The mixing ratio control pipe 97 includes a mixing ratio control valve 99. The bypass pipe 98 branches from the main pipe of the cooling medium / turbo pump drive medium supply line 92 on the downstream side of the branch portion of the merging pipe 96 and on the upstream side of the thrust control valve 95, and The turbine 52 and the turbine 62 are bypassed by connecting to the downstream side. The bypass pipe 98 includes a waist valve 98a.

The main fuel valve 93 adjusts the supply of LH ₂ to the injector 102 by opening and closing the fuel supply line 90. The main oxidant valve 94 adjusts the supply of LOx to the injector 102 by opening and closing the oxidant supply line 91. The combustion chamber cooling valve 92 c adjusts the circulation of LH ₂ and GH _{2 in} the cooling medium / turbo pump driving medium supply line 92 by opening and closing the cooling medium / turbo pump driving medium supply line 92. The thrust control valve 95 controls the number of revolutions of the turbine 52 by opening and closing the cooling medium / turbo pump drive medium supply line 92 to control the amount of GH ₂ introduced as the drive medium introduced into the turbine 52. With the above configuration, the thrust of the rocket engine 100 as a whole is controlled by controlling the pressurization of LH ₂ by the pump 51.

The mixing ratio control valve 99 controls the rotational speed of the turbine 62 by opening and closing the mixing ratio control pipe 97 to control the introduction amount of GH ₂ as a driving medium introduced into the turbine 62. With this configuration, by controlling the pressurization of LOx by the pump 61, the mixing ratio (LOx / GH ₂ ) in the entire rocket combustor 101, that is, the ratio of LOx and GH ₂ injected from the injector 102. Is controlled. When the GH ₂ vaporized by passing through the cooling passage 105 bypasses the turbine 52 and the turbine 62, the waist valve 98a opens and closes according to the bypass amount.

The mixer 70 mixes the cryogenic LH ₂ that has passed through the main fuel valve 93 and the hot GH ₂ that has vaporized after passing through the cooling passage 105, so that it can be supplied to the rocket combustor 101 as GH ₂ . Note that hydrogen as a fuel may have gas-liquid two phases of GH ₂ and LH _{2 on} the downstream side of the cooling passage 105 in the cooling medium / turbo pump drive medium supply line 92.

The rocket engine 100 configured as described above pumps LH ₂ supplied through the fuel supply line 90 to the rocket combustor 101 by the fuel turbo pump 50 and also through the oxidant supply line 91. The supplied LOx is pumped to the rocket combustor 101 by the oxidant turbo pump 60.

Rocket engine 100, a LOx and GH ₂ were mixed in the combustion chamber 103 of the rocket combustor 101, obtain the thrust by burning by ignition by the igniter 80 to the mixture. During this time, the cooling medium / turbo pump drive medium supply line 92 introduces part of the LH ₂ pumped by the fuel turbo pump 50 into the cooling passage 105 provided on the wall surface of the combustion chamber 103 in the rocket combustor 101. . Then, the low temperature LH ₂ cools the combustion chamber 103. LH _{2 that} has gained energy by cooling the combustion chamber 103 rises in temperature and gasifies to become GH ₂ . A part of the gasified GH ₂ is introduced into the mixer 70 through the junction pipe 96 and is mixed with LH _{2 in the} mixer 70.

The remaining GH ₂ is sequentially introduced into the turbine 52 of the turbo pump 50 for fuel and the turbine 62 of the turbo pump 60 for oxidant, and acts as a driving medium for the turbine 52 and the turbine 62. The turbine 62 is driven to rotate. Accordingly, as described above, the turbo pump 50 for fuel and the turbo pump 60 for oxidant pump LH ₂ and LOx. The GH ₂ that rotationally drives the turbine 52 and the turbine 62 is discarded into the nozzle 104 from the other end of the cooling medium / turbo pump driving medium supply line 92.

In this rocket engine 100, the fuel turbo pump 50, which has a high density and therefore requires a high output, is first driven by GH ₂ and then the oxidant turbo pump 60 is driven. The pressure of GH ₂ after driving the fuel turbo pump 50 and the oxidant turbo pump 60 is considerably lower than the pressure before the first turbine 52 inlet, and the pressure before the turbine 52 inlet. Therefore, it is discharged into the nozzle 104 as a low pressure portion of the rocket combustor 101.

<Turbo pump>
FIG. 2 is a schematic configuration diagram of the turbo pump according to the present embodiment. The turbo pump 50 or the turbo pump 60 includes a main shaft 1 that is rotationally driven, an impeller 10 that is fixed to the main shaft 1, a turbine blade 8 that is fixed to the main shaft 1, an inducer 6 that introduces liquid, and a casing 2. The bearing 4 and the bearing 5 that support the rotation of the main shaft 1 and the mechanical seal 7 that prevents liquid such as LOx and GH ₂ from leaking from the gap between the main shaft 1 and the casing 2 are included. In the turbo pump 50 or the turbo pump 60, the main shaft 1 connects the impeller 10 and the turbine blade 8 in series.

The inducer 6 is an axial flow type impeller, and is accommodated in the casing 2 so as to be coaxially connected to the turbine blade 8 and the impeller 10 and the main shaft 1. The direction of arrow Pi indicates the supply direction of LH ₂ or LOx supplied from the fuel tank or oxidant tank. When the turbine blade 8 is rotated by high-temperature and high-pressure gas and the interlocking impeller 10 is rotationally driven, the impeller of the inducer 6 rotates in synchronization with this. For this reason, the inducer 6 guides LH ₂ or LOx to the suction port of the impeller 10 and suppresses cavitation generated in the impeller of the impeller 10 in order to maintain the suction performance of the impeller 10.

The impeller 10 is rotated in the casing 2 and acts as a centrifugal pump. That is, the pumps 51 and 61 are centrifugal pumps that pressurize the fluid sucked through the inducer 6 with centrifugal force. The impeller 10 pressurizes the liquid (fluid) such as LOx and LH ₂ sucked through the inducer 6 and gives energy to the liquid such as LOx and LH ₂ . Pressurized liquids such as LOx and LH ₂ are discharged in the direction of the arrow Po and supplied to the fuel supply line 90 or the oxidant supply line 91 shown in FIG.

As described above, the turbines 52 and 62 pass through the cooling passage 105 shown in FIG. 1 and vaporize, and are driven to rotate by GH ₂ supplied from the direction of the arrow Gi. That is, GH _{2 as} a driving medium pushes the turbine blade 8 to rotate the main shaft 1. Note that the driving medium GH ₂ is discharged in the direction of the arrow Go and is sent to the combustion chamber 103 as shown in FIG.

  FIG. 3 is a schematic partial cross-sectional view illustrating the pump of the turbo pump according to the first embodiment. As shown in FIG. 3, the casing 2 includes a stationary wall 3 located on the impeller 10 on the turbine blade 8 side. The impeller 10 includes a front shroud 11 and a rear shroud 15 so as to cover the outer peripheral surface of the impeller 10. A first flow path 12 through which liquid flows is formed in a gap between the outer peripheral surface of the front shroud 11 and the casing 2 facing the front shroud 11. In the first flow path 12, a throttle is formed by a protrusion provided on the inner diameter side of the front shroud 11 of the impeller 10 and a protrusion formed in the casing 2 facing the protrusion.

  A second flow path 16 through which liquid flows is formed in a gap between the rear shroud 15 of the impeller 10 and the stationary wall 3 facing the impeller 10. The second flow path 16 includes a multistage orifice including a first orifice 17 and a second orifice 18. The 1st orifice 17 and the 2nd orifice 18 adjust the pressure of the 2nd flow path 16, maintain an axial direction balance, and reduce a possibility that the impeller 10 may contact with another member.

  Further, the balance hole 19 is connected to the second flow path 16, and the liquid in the second flow path 16 is returned to the blade inlet of the impeller 10. The balance hole 19 is inclined so that the side communicating with the wing is located on the radially outer side than the side communicating with the second flow path 16. For this reason, the liquid returning from the balance hole 19 can suppress turbulent flow that disturbs the inflow direction of the main flow of the impeller 10. As a result, the pumps 51 and 61 can maintain the pump performance.

<Bearing cooling mechanism>
The bearing cooling flow path 21 branched from the second flow path 16 is a flow for guiding a part of liquid such as LOx, LH ₂ pressurized to the bearing cooling mechanism for lubrication and cooling of the bearing 4 and the bearing 5. Road. The bearing 4 and the bearing 5 rotate between the bearing inner ring 42 connected to the main shaft 1, the bearing outer ring 43 connected to the casing 2, the bearing inner ring 42 and the bearing outer ring 43, and the rotation direction of the main shaft 1. Rolling elements 41 revolving in the same direction. The bearing cooling mechanism according to the first embodiment includes an orifice 22, a guide vane 31, and a rectifying space 24.

  The rectifying space 24 is a space adjacent to the bearing 4, and is partitioned by the seal member 23. The seal member 23 is fixed to the casing 2. The orifices 22 are a plurality of constricted openings in the circumferential direction, and cause a pressure difference between the bearing cooling flow path 21 and the rectifying space 24. Thereby, the orifice 22 produces the jet c1 which goes to the main shaft 1 from the outer peripheral side. The guide vane 31 rectifies the direction of the jet flow c <b> 1 in the rectifying space 24 to make a swirl flow. A plurality of guide vanes 31 are provided in the circumferential direction around the main shaft 1. With this configuration, the direction of the jet flow c1 can be made uniform in the rectifying space 24. For example, when the number provided in the circumferential direction of the orifice 22 is n, the number provided in the circumferential direction of the guide blade 31 is preferably n + 1 or more.

  The jet c1 in the rectifying space 24 passes between the bearing inner ring 42 and the bearing outer ring 43 in the bearing 4 while turning in the rotation direction of the main shaft 1 as described later. The jet flow c1 becomes a cooling flow c2 sent out toward the bearing 5 while cooling the bearing 4. The cooling flow c <b> 2 passes between the bearing inner ring 42 and the bearing outer ring 43 in the bearing 5 and becomes a cooling flow c <b> 3 that is sent toward the balance hole 19 while cooling the bearing 5. The cooling flow c <b> 3 becomes a part of the recirculation c <b> 4 discharged to the blade inlet of the impeller 10 through the balance hole 19. FIG. 4 is an explanatory diagram for explaining a bearing cooling mechanism of the turbo pump according to the first embodiment. FIG. 4 is an explanatory view of the rectifying space 24 taken along a plane orthogonal to the axial direction of the main shaft 1 of FIG.

  The main shaft 1 rotates relative to the casing 2. As shown in FIG. 4, when the rotation center of the main shaft 1 is Zr, the revolution diameter D2 of the rolling element 41 passing through the rotation center Zr is larger than the diameter D1 of the main shaft 1. Here, assuming that the circumferential speed of the main shaft 1 is V1 and the rotation speed is N, V1 can be expressed by the following formula (1).

  Further, the rolling element 41 of the bearing 4 shown in FIG. 4 revolves and rolls in the same direction as the rotation direction of the main shaft 1. If the speed of rolling in the revolution direction B of the rolling element 41 of the bearing 4 is V2, V2 can be similarly expressed by the following formula (2). Here, k is a constant inherent to the bearing 4 and is a coefficient smaller than 1.

  The velocity Vθ of the jet c1 described above is expressed by the following equation, where ρ is the viscosity of the liquid constituting the jet c1, and ΔP is the pressure difference between the bearing cooling flow path 21 and the rectifying space 24 generated by the orifice 22. (3).

  Since the revolution of the rolling element 41 of the bearing 4 is regulated between the bearing inner ring 42 and the bearing outer ring 43, the jet flow c <b> 1 is caused by the rolling element 41 by setting the component in the revolution direction of the velocity Vθ of the jet c <b> 1 to V <b> 2 or more. You can apply a force to assist in the revolution. That is, when the relationship between the speed V2 of the rolling element 41 of the bearing 4 in the revolution direction and the speed Vθ of the jet c1 satisfies the relationship expressed by the following formula (4), the jet c1 works on the rolling element 41. Can do.

  In order to increase the revolution direction component of the velocity Vθ of the jet flow c1, the guide vane 31 shown in FIG. 4 changes the direction of the jet flow c1 and turns the jet flow c1 along the revolution direction B of the rolling element 41 of the bearing 4. . For this reason, the guide vane 31 inclines the flow in the revolution direction B so that the jet distance of the jet flow c <b> 1 is longer than the linear distance from the orifice 22 to the main shaft 1. In this way, the guide vane 31 adjusts the flow of the jet c1 so as to increase the speed component of the main shaft 1 in the rotation direction.

  As described above, the turbo pump according to the first embodiment includes the main shaft 1 that is rotated by the turbine blades 8 in the casing 2, the bearing inner ring 42 that is connected to the main shaft 1, the bearing outer ring 43 that is connected to the casing 2, and the bearing inner ring. 42 and a rolling element 41 that rotates between the outer ring 43 and the bearing outer ring 43, and a bearing cooling mechanism. The bearing cooling mechanism includes an orifice 22 and guide vanes 31. The orifice 22 is a fluid throttle mechanism, and generates a jet c1 in which a fluid pressurized by an impeller 10 that rotates in conjunction with the main shaft 1 is ejected. The guide vane 31 is a fluid rectifier, and rectifies the flow of the jet c1 so as to increase the velocity component in the rotation direction of the main shaft 1, that is, the revolution direction B.

  With this configuration, the fluid of the jet c <b> 1 is used for lubricating and cooling the bearing 4. Moreover, the turbo pumps 50 and 60 can reduce the loss of rolling in the circumferential direction of the rolling element 41. Thereby, the jet flow c1 can assist the movement in the circumferential direction of the rolling element 41 that rolls. As a result, the energy that the rolling element 41 acts on the jet c1 can be reduced, and the resistance to rotation of the main shaft 1 of the turbo pumps 50 and 60 can be suppressed. The turbo pumps 50 and 60 can cool the bearing 4 while reducing the loss of the bearing 4.

  Since the rolling element 41 of the bearing 4 reduces the energy which acts on the jet flow c1, the temperature rise of the cooling flow c2 can be suppressed. For this reason, the cooling flow c <b> 2 can cool the bearing 5.

  The turbo pumps 50 and 60 include guide vanes 31 that do not rotate in conjunction with the main shaft 1. By the guide vanes 31, the jet flow c <b> 1 can create a flow of a speed component equal to or higher than the speed of the rolling elements 41 in the rotation direction of the main shaft 1, that is, the direction of the revolution direction B.

  Since the rolling element 41 of the bearing 4 reduces the energy which acts on the jet flow c1, the temperature rise of the cooling flow c2 can be suppressed. For this reason, the cooling flow c <b> 2 can cool the bearing 5.

(Embodiment 2)
Next, a bearing cooling mechanism according to the second embodiment will be described. FIG. 5 is an explanatory diagram for explaining a bearing cooling mechanism of the turbo pump according to the second embodiment. In the following description, the same components as those in the above-described embodiment are denoted by the same reference numerals, and redundant description is omitted.

  The bearing cooling mechanism according to the second embodiment includes an orifice 22, a fluid rectifying surface 32, and a rectifying space 24. The fluid rectifying surface 32 is a fluid rectifying unit and regulates the direction of the jet c1 integrally with the orifice 22 which is a fluid throttle mechanism. The jet c <b> 1 of the second embodiment is restricted by the fluid rectifying surface 32 at the time when the jet c <b> 1 is ejected from the orifice 22 and turns along the revolution direction B of the rolling element 41 of the bearing 4. The fluid rectifying surface 32 adjusts the flow of the jet c1 so as to increase the velocity component in the rotation direction of the main shaft 1. And the fluid rectification | straightening surface 32 cools the rolling element 41 with the flow of the jet flow c1.

  With this configuration, the fluid of the jet c <b> 1 is used for lubricating and cooling the bearing 4. The jet flow c <b> 1 can create a flow of a speed component equal to or higher than the speed of the rolling element 41 in the rotation direction of the main shaft 1, that is, the direction of the revolution B. Thereby, the jet flow c1 can assist the movement in the circumferential direction of the rolling element 41 that rolls. As a result, the energy that the rolling element 41 acts on the jet c1 can be reduced, and the resistance to rotation of the main shaft 1 of the turbo pumps 50 and 60 can be suppressed. The turbo pumps 50 and 60 can cool the bearing 4 while reducing the loss of the bearing 4.

  The bearing cooling mechanism can further include the guide blade 31 of the first embodiment described above. With this structure, the flow of the jet c1 is adjusted and rectified so as to further increase the velocity component in the revolution direction B.

(Embodiment 3)
Next, a bearing cooling mechanism according to the third embodiment will be described. FIG. 6 is a schematic partial sectional view showing a pump of the turbo pump according to the third embodiment. FIG. 7 is an explanatory diagram for explaining a bearing cooling mechanism of the turbo pump according to the third embodiment. In the following description, the same components as those in the above-described embodiment are denoted by the same reference numerals, and redundant description is omitted.

  The bearing cooling mechanism according to the third embodiment includes an orifice 22 and a guide vane 33. As shown in FIGS. 6 and 7, the guide vane 33 is a fluid rectifying unit and is a moving vane that rotates in conjunction with the main shaft 1. As described above, the speed of the jet c1 is higher than the rotational speed V1 in the circumferential direction of the main shaft 1 when the pressure difference ΔP between the bearing cooling flow path 21 and the rectifying space 24 is large. When the speed of the jet c <b> 1 is higher than the rotational speed V <b> 1 in the circumferential direction of the main shaft 1, cavitation may occur in the rectifying space 24.

  The bearing cooling mechanism according to the third embodiment is a moving blade in which the guide vane 33 rotates in conjunction with the main shaft 1, and can recover the energy of the jet c <b> 1 as the rotation of the main shaft 1 in the circumferential direction. Thereby, the temperature of the jet c1 can be lowered and the cavitation margin can be widened. Further, the jet c1 is rectified while the guide vane 33 rotates in conjunction with the main shaft 1. For this reason, the jet flow c1 is rectified in the direction of the jet flow c1 by the guide vanes 33 interlocked with the rotation of the main shaft 1 in the same manner as in FIG. 4 and swirled so that the jet flow c1 follows the revolution direction B of the rolling element 41 of the bearing 4. To do. The guide vane 33 adjusts the flow of the jet c1 so as to increase the velocity component in the rotation direction of the main shaft 1. And the guide blade 33 cools the rolling element 41 with the flow of the jet flow c1.

  The bearing cooling mechanism may further include one or more of the guide vanes 31 in the first embodiment and the fluid rectifying surface 32 in the second embodiment. With this structure, the flow of the jet c1 can be adjusted and rectified so as to further increase the velocity component in the revolution direction B. Further, with this structure, the energy of the jet c1 can be further recovered as the rotation of the main shaft 1 in the circumferential direction.

DESCRIPTION OF SYMBOLS 1 Main shaft 2 Casing 3 Static wall 4, 5 Bearing 6 Inducer 7 Mechanical seal 8 Turbine blade 10 Impeller 11 Front shroud 12 Channel 15 Rear shroud 16 Channel 17 First orifice 18 Second orifice 19 Balance hole 21 Bearing cooling channel 22 Orifice 23 Seal member 24 Rectifying space 31 Guide vane 32 Fluid rectifying surface 33 Guide vane 41 Rolling element 42 Bearing inner ring 43 Bearing outer ring 50, 60 Turbo pump 51, 61 Pump 52, 62 Turbine 70 Mixer 80 Igniter 90 Fuel supply line 91 Oxidant supply line 92 Cooling medium / turbo pump drive medium supply line 93 Main fuel valve 94 Main oxidant valve 95 Thrust control valve 96 Junction pipe 97 Mixing ratio control pipe 98 Bypass pipe 99 Mixing ratio control valve 100 Rocket engine 1 01 rocket combustor 102 injector 103 combustion chamber 104 nozzle 105 cooling passage B revolution direction c1 jet c2, c3 cooling flow c4 reflux

Claims (4)

A main shaft rotated by turbine blades in the casing;
A bearing including a bearing inner ring connected to the main shaft, a bearing outer ring connected to the casing, and a rolling element that rotates between the bearing inner ring and the bearing outer ring;
A fluid throttle mechanism for generating a jet flow in which a pressurized fluid is jetted by an impeller that rotates in conjunction with the main shaft, and the flow of the jet flow is adjusted and rectified so as to increase a velocity component in the rotation direction of the main shaft, A fluid rectifier that cools the rolling elements, and a bearing cooling mechanism,
The turbo pump characterized by including.   The turbo pump according to claim 1, wherein the fluid rectifier does not rotate in conjunction with the main shaft.   The turbo pump according to claim 1, wherein the fluid rectifying unit is integrated with the fluid throttle mechanism and regulates a jet direction.   The turbo pump according to claim 1, wherein the fluid rectifying unit is a moving blade that rotates in conjunction with the main shaft.

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