CN110481578B - Control method of drag reduction system of high-speed train - Google Patents
Control method of drag reduction system of high-speed train Download PDFInfo
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- CN110481578B CN110481578B CN201910785432.0A CN201910785432A CN110481578B CN 110481578 B CN110481578 B CN 110481578B CN 201910785432 A CN201910785432 A CN 201910785432A CN 110481578 B CN110481578 B CN 110481578B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61D—BODY DETAILS OR KINDS OF RAILWAY VEHICLES
- B61D17/00—Construction details of vehicle bodies
- B61D17/02—Construction details of vehicle bodies reducing air resistance by modifying contour ; Constructional features for fast vehicles sustaining sudden variations of atmospheric pressure, e.g. when crossing in tunnels
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T30/00—Transportation of goods or passengers via railways, e.g. energy recovery or reducing air resistance
Abstract
The invention discloses a high-speed train and a control method of a drag reduction system of the high-speed train. The high-speed train comprises a drag reduction system, a train body, a train head and a train tail, wherein the train head and the train tail are respectively connected with the two ends of the train body; the outer surface of the telescopic shell is provided with a first group of pressure sensors, and the head and the tail of the vehicle are provided with first air injection pipelines which correspond to the first group of pressure sensors one by one and are matched with the telescopic shell; a first flow guide part is arranged at the outlet of the first air injection pipeline; the other end of the first air injection pipeline is connected with a high-pressure air storage device of the air storage unit, and a first air outlet control valve is arranged on the first air injection pipeline; the air inlet end of the high-pressure air storage device is connected with an air compressor through an air inlet pipeline; the control unit is respectively connected with the first group of pressure sensors, the first air outlet control valve and the air compressor.
Description
Technical Field
The invention relates to the field of traffic, in particular to a control method of a drag reduction system of a high-speed train.
Background
In recent years, the high-speed train industry is vigorously developed in China, and the running speed of the high-speed train industry is continuously increased, so that the problems of the high-speed train industry in certain aspects are increasingly highlighted.
Among them, air resistance has become a problem to be ignored. Research shows that the air resistance of the high-speed train is in direct proportion to the square of the running speed, and when the speed of the high-speed train reaches 300km/h, the air resistance can reach 80% of the total resistance; when the speed of the high-speed train reaches 350km/h, the air resistance can reach 90 percent of the total resistance. In order to realize further speed increase of high-speed trains and improve the dynamic performance of the trains, research on the resistance reduction measures of the trains is necessary.
The surface friction resistance and the pressure difference resistance jointly form the air resistance of the high-speed train. In operation, the air flow layer near the surface of the vehicle body can generate friction with the surface of the vehicle body due to the viscosity of the air, so that surface friction resistance is formed. Meanwhile, when the train operates, the high-speed train and static air generate relative motion, the air in front of the train head is stamped to form positive pressure, the air generates vortex when flowing around to the train tail to form negative pressure, and the front and rear pressure differences generate pressure difference resistance.
Disclosure of Invention
In view of the above-mentioned disadvantages in the prior art, the present invention aims to provide a control method for a drag reduction system of a high-speed train capable of reducing air resistance
In order to achieve the purpose of the invention, the invention adopts the technical scheme that:
the high-speed train comprises a drag reduction system, a train body, a train head and a train tail, wherein the train head and the train tail are respectively connected with the two ends of the train body; the outer surface of the telescopic shell is provided with a first group of pressure sensors, and the head and the tail of the vehicle are provided with first air injection pipelines which correspond to the first group of pressure sensors one by one and are matched with the telescopic shell; a first flow guide piece for adjusting the air injection direction is arranged at the outlet of the first air injection pipeline and is controlled by a second driving part connected with the control unit; the other end of the first air injection pipeline is connected with a high-pressure air storage device of the air storage unit, and a first air outlet control valve is arranged on the first air injection pipeline; the air inlet end of the high-pressure air storage device is connected with an air compressor through an air inlet pipeline; the control unit is respectively connected with the first group of pressure sensors, the first air outlet control valve and the air compressor.
Further, the first group of pressure sensors comprises 4 pressure sensors distributed in a ring shape.
The telescopic arc-shaped plates are respectively arranged on the vehicle head and the vehicle tail and are matched with the corresponding telescopic shells, the telescopic arc-shaped plates are controlled by a third driving part connected with the control unit, the telescopic arc-shaped plates are positioned on one sides, close to the vehicle body, of the corresponding telescopic shells, the vehicle head, the corresponding telescopic arc-shaped plates and the corresponding telescopic shells are integrally streamline, and the telescopic shells are controlled by a first driving part connected with the control unit; the tail of the vehicle, the corresponding telescopic arc-shaped plate and the corresponding telescopic shell are integrally streamline; the outer surface of the telescopic arc-shaped plate is provided with a second group of pressure sensors connected with the control unit, the vehicle head and the vehicle tail are provided with a second group of pressure sensors in one-to-one correspondence with the first group of pressure sensors and a second air injection pipeline matched with the telescopic arc-shaped plate, the outlet of the second air injection pipeline is provided with a second flow guide part used for adjusting the air injection direction, the second flow guide part is controlled by a fourth driving part connected with the control unit, the other end of the second air injection pipeline is connected with a high-pressure air storage device of the air storage unit, and the second air injection pipeline is provided with a second air outlet control valve connected with the control unit.
Further, the second group of pressure sensors comprises 3 pressure sensors distributed in a fan shape.
On the other hand, the scheme also provides a control method of the drag reduction system of the high-speed train, which comprises the following steps:
s1, starting a jet output unit arranged on the tail of the vehicle, jetting corresponding to all jet pipelines at a set initial angle and a set initial jet speed, and then synchronously entering the steps S2 and S3;
s2, acquiring the pressure of the positions of all the pressure sensors to obtain first pressure difference between the corresponding positions of the vehicle head and the vehicle tail, judging whether the absolute values of all the first pressure difference are smaller than or equal to a set pressure difference, if so, entering a step S4, and otherwise, entering a step S5;
s3, collecting the pressure intensity in the high-pressure gas storage device, judging whether the pressure intensity in the high-pressure gas storage device is in a set range, if not, entering the step S6, and if yes, returning to the step S3;
s4, adjusting all the flow guide pieces on the tail of the vehicle to various angles and keeping set time, acquiring the pressure of the positions of all the pressure sensors after each adjustment is finished to obtain second pressure difference between the corresponding positions of the vehicle head and the tail of the vehicle, taking the angle of the flow guide piece corresponding to the minimum value of all the second pressure differences under each group of corresponding positions as an optimal angle, keeping the flow guide piece at the corresponding optimal angle, and then entering the step S2;
s5, adjusting the jet speed of the jet pipeline and then entering the step S2;
s6, after the working state of the air compressor is adjusted and controlled, the process goes to step S3.
The invention has the beneficial effects that:
because the high-speed train needs to go up and down, the car head and the car tail are both provided with the jet output units, so that when the high-speed train runs, the jet output units arranged on the car tail are controlled to jet air to a set area (namely the outer surface of the telescopic shell) on the surface of the car tail, thereby effectively improving the distribution of the airflow of the boundary layer on the surface of the train body and reducing the air friction resistance of the train caused by air viscosity; meanwhile, the separation of airflow at the tail of the vehicle is inhibited, and the pressure applied to the tail of the vehicle is increased, so that the pressure difference between the head of the vehicle and the tail of the vehicle is reduced. The invention realizes active drag reduction, actively controls the air injection direction and the air injection speed of the air injection pipeline in the air injection output unit in due time by combining the air storage unit, the air injection output unit and the control unit, and achieves better drag reduction effect.
When the telescopic shell is in an extending state, the telescopic shell and the corresponding vehicle head and the corresponding vehicle tail are respectively in a streamline shape, so that the surface of the vehicle head in actual operation is smoothed, and the phenomenon that the air flow separation generates interference resistance due to the newly added protruding part is avoided.
Drawings
FIG. 1 is a partial schematic view of a vehicle head in an exemplary embodiment with both the telescoping shell and the telescoping arcuate panels in an extended position;
FIG. 2 is a partial schematic view of the tailstock of FIG. 1 with the retractable housing and the retractable arc both in a retracted state;
FIG. 3 is a functional block diagram of the control portion of FIG. 1;
FIG. 4 is a left side view of the telescoping shell;
FIG. 5 is a left side view of the telescoping arcuate plate;
fig. 6 is a flowchart of a control method of the drag reduction system of a high-speed train according to the present invention.
Wherein, the arrow indicates the direction of the air jet flow, 1, the telescopic shell; 2. a retractable arc plate; 3. a headstock; 4. a jet outlet gap; 5. a first set of pressure sensors; 6. a second set of pressure sensors; 7. the tail of the vehicle.
Detailed Description
The following detailed description of the present invention will be provided in conjunction with the accompanying drawings to facilitate the understanding of the present invention by those skilled in the art. It should be understood that the embodiments described below are only some embodiments of the invention, and not all embodiments. All other embodiments obtained by a person skilled in the art without any inventive step, without departing from the spirit and scope of the present invention as defined and defined by the appended claims, fall within the scope of protection of the present invention.
As shown in fig. 1 and 2, the high-speed train comprises a drag reduction system, a train body, a train head 3 and a train tail 7, wherein the train head 3 and the train tail 7 are respectively connected with the two ends of the train body, the drag reduction system comprises jet output units positioned on the train head 3 and the train tail 7, and the jet output units comprise telescopic shells 1 positioned at the end parts. When the telescopic shell 1 is in an extending state, the telescopic shell and the corresponding vehicle head 3 and the corresponding vehicle tail 7 are respectively in a streamline shape, so that the running of a high-speed train is not influenced.
As shown in fig. 3, the retractable housing 1 is controlled by a first driving part connected to the control unit (to control the retractable state of the retractable housing), a first set of pressure sensors 5 is disposed on the outer surface of the retractable housing 1, and first air injection pipes corresponding to the first set of pressure sensors 5 and matched with the retractable housing 1 are disposed on the head 3 and the tail 7; a first flow guide part for adjusting the air injection direction is arranged at the outlet of the first air injection pipeline, and the first flow guide part is controlled by a second driving part connected with the control unit (controls the first flow guide part to act); the other end of the first air injection pipeline is connected with a high-pressure air storage device of the air storage unit, and a first air outlet control valve is arranged on the first air injection pipeline; the air inlet end of the high-pressure air storage device is connected with an air compressor through an air inlet pipeline; the control unit is connected with the first group of pressure sensors 5, the first air outlet control valve and the air compressor respectively.
As shown in fig. 2, when the jet output unit is activated, the corresponding retractable housing 1 is moved downward and toward the vehicle body by a distance so as to form a jet outlet gap 4 to expose all the outlets of the first jet ducts, during which the first group of pressure sensors 5 remains exposed.
In practice, as shown in fig. 4, the outer surface of the retractable casing 1 preferably presents a half ellipsoid shape, similar to the end of the existing high-speed train, and the first group of pressure sensors 5 comprises 4 pressure sensors distributed in a ring shape. And the first flow guide piece is a flow guide strip, and all the flow guide strips are parallel to each other.
In addition, as shown in fig. 1 and fig. 2, the high-speed train further includes two retractable arc-shaped plates 2 respectively installed on the train head 3 and the train tail 7 and matched with the corresponding retractable housing 1, the retractable arc-shaped plates 2 are controlled by a third driving portion connected with the control unit, the retractable arc-shaped plates 2 are located on one side of the corresponding retractable housing 1 close to the train body, the train head 3 is streamline with the corresponding retractable arc-shaped plates 2 and the corresponding retractable housing 1, and the train tail 7 is streamline with the corresponding retractable arc-shaped plates 2 and the corresponding retractable housing 1.
The outer surface of the telescopic arc-shaped plate 2 is provided with a second group of pressure sensors 6 connected with the control unit, the vehicle head 3 and the vehicle tail 7 are provided with a first group of pressure sensors 5 in one-to-one correspondence, and are provided with a second air injection pipeline matched with the telescopic arc-shaped plate 2, the outlet of the second air injection pipeline is provided with a second air guide part used for adjusting the air injection direction, the second air guide part is controlled by a fourth driving part connected with the control unit, the other end of the second air injection pipeline is connected with a high-pressure air storage device of the air storage unit, and the second air injection pipeline is provided with a second air outlet control valve connected with the control unit.
As shown in fig. 2, when the jet output unit is activated, the retractable arc 2 moves downward and toward the vehicle body by a distance, thereby forming a jet outlet gap 4 to expose the outlets of all the second jet ducts, which jet the jet toward the retractable arc 2, while the second group of pressure sensors 6 remain exposed.
As shown in fig. 5, the second group of pressure sensors 6 comprises 3 pressure sensors distributed in a fan shape.
As shown in fig. 6, the present scheme further provides a control method of the drag reduction system of a high-speed train, which includes:
s1, starting a jet output unit arranged on the tail 7, jetting corresponding to all jet pipelines at a set initial angle and a set initial jet speed, and then synchronously entering the steps S2 and S3; the tail 7 is the actual tail 7;
s2, acquiring the pressure of the positions of all the pressure sensors to obtain a first pressure difference between the positions corresponding to the vehicle head 3 and the vehicle tail 7, and judging whether the absolute values of all the first pressure differences are smaller than or equal to a set pressure difference, if so, entering a step S4, otherwise, entering a step S5;
s3, collecting the pressure intensity in the high-pressure gas storage device, judging whether the pressure intensity in the high-pressure gas storage device is in a set range, if not, entering the step S6, and if yes, returning to the step S3;
s4, adjusting all the flow guide pieces on the tail 7 to various angles and keeping set time, acquiring the pressure of the positions of all the pressure sensors after each adjustment is finished to obtain second pressure difference between the corresponding positions of the head 3 and the tail 7, taking the angle of the flow guide piece corresponding to the minimum value in all the second pressure differences under each group of corresponding positions as the optimal angle, keeping the flow guide piece at the corresponding optimal angle, and then entering the step S2;
s5, adjusting the jet speed of the jet pipeline and then entering the step S2; specifically, if the value of the first pressure difference is positive, the air injection speed is increased through the air outlet control valve, and if the value of the first pressure difference is negative, the air injection speed is reduced through the air outlet control valve;
and S6, adjusting and controlling the working state of the air compressor, and then entering the step S3, if the pressure in the high-pressure air storage device is lower than the set range, increasing the pressure in the high-pressure air storage device by controlling the working state of the air compressor, and if the pressure in the high-pressure air storage device is higher than the set range, decreasing the pressure in the high-pressure air storage device by controlling the working state of the air compressor.
In practice, steps S2 and S3 are not mandatory in a sequential order. And in order to make the air outlet of the jet output unit more stable, the air inlet pipeline is provided with an air inlet control valve connected with the control unit, and the working states of the air inlet control valve and the air compressor are controlled together in step S6 so that the pressure inside the high-pressure air storage device is within a set range.
Claims (4)
1. The control method of the drag reduction system of the high-speed train is characterized in that the high-speed train comprises the drag reduction system, a train body, a train head (3) and a train tail (7) which are respectively connected with the two ends of the train body, the drag reduction system comprises jet output units positioned on the train head (3) and the train tail (7), each jet output unit comprises a telescopic shell (1) positioned at the end part, when the telescopic shell (1) is in an extending state, the telescopic shell, the corresponding train head (3) and the corresponding train tail (7) are respectively in a streamline shape, and the telescopic shell (1) is controlled by a first driving part connected with the control unit; a first group of pressure sensors (5) are arranged on the outer surface of the telescopic shell (1), and first air injection pipelines which correspond to the first group of pressure sensors (5) one by one and are matched with the telescopic shell (1) are arranged on the vehicle head (3) and the vehicle tail (7); a first flow guide piece for adjusting the air injection direction is arranged at the outlet of the first air injection pipeline, and the first flow guide piece is controlled by a second driving part connected with the control unit; the other end of the first air injection pipeline is connected with a high-pressure air storage device of the air storage unit, and a first air outlet control valve is arranged on the first air injection pipeline; the air inlet end of the high-pressure air storage device is connected with an air compressor through an air inlet pipeline; the control unit is respectively connected with the first group of pressure sensors (5), the first air outlet control valve and the air compressor;
the control method comprises the following steps:
s1, starting a jet output unit arranged on the tail (7), jetting corresponding to all jet pipelines at a set initial angle and a set initial jet speed, and then synchronously entering the steps S2 and S3;
s2, acquiring the pressure of the positions of all the pressure sensors to obtain a first pressure difference between the corresponding positions of the vehicle head (3) and the vehicle tail (7), judging whether the absolute values of all the first pressure differences are smaller than or equal to a set pressure difference, if so, entering a step S4, and otherwise, entering a step S5;
s3, collecting the pressure intensity in the high-pressure gas storage device, judging whether the pressure intensity in the high-pressure gas storage device is in a set range, if not, entering the step S6, and if yes, returning to the step S3;
s4, adjusting all the flow guide pieces on the tail (7) to various angles and keeping set time, acquiring the pressure of the positions of all the pressure sensors after each adjustment is finished to obtain second pressure difference between the corresponding positions of the head (3) and the tail (7), taking the angle of the flow guide piece corresponding to the minimum value in all the second pressure differences under each group of corresponding positions as an optimal angle, keeping the flow guide piece at the corresponding optimal angle, and then entering the step S2;
s5, adjusting the jet speed of the jet pipeline and then entering the step S2;
s6, after the working state of the air compressor is adjusted and controlled, the process goes to step S3.
2. The control method of the drag reduction system of a high-speed train according to claim 1, characterized in that the first group of pressure sensors (5) comprises 4 pressure sensors distributed in a ring shape.
3. The control method of the drag reduction system of the high-speed train according to claim 1 or 2, wherein the high-speed train further comprises two retractable arc-shaped plates (2) which are respectively arranged on the head (3) and the tail (7) and are matched with the corresponding retractable shells (1), the retractable arc-shaped plates (2) are controlled by a third driving part connected with the control unit, the retractable arc-shaped plates (2) are positioned on one sides of the corresponding retractable shells (1) close to the train body, the head (3) is streamline with the corresponding retractable arc-shaped plates (2) and the corresponding retractable shells (1) as a whole, and the tail (7) is streamline with the corresponding retractable arc-shaped plates (2) and the corresponding retractable shells (1) as a whole; the outer surface of the telescopic arc-shaped plate (2) is provided with a second group of pressure sensors (6) connected with the control unit, the locomotive (3) and the tailstock (7) are provided with a second group of pressure sensors (5) in one-to-one correspondence, and the telescopic arc-shaped plate (2) is matched with a second air injection pipeline, the outlet of the second air injection pipeline is provided with a second flow guide part used for adjusting the air injection direction, the second flow guide part is controlled by a fourth driving part connected with the control unit, the other end of the second air injection pipeline is connected with a high-pressure air storage device of the air storage unit, and the second air injection pipeline is provided with a second air outlet control valve connected with the control unit.
4. The control method of the drag reduction system of a high-speed train according to claim 3, characterized in that the second group of pressure sensors (6) comprises 3 pressure sensors distributed in a fan shape.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201910785432.0A CN110481578B (en) | 2019-08-23 | 2019-08-23 | Control method of drag reduction system of high-speed train |
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| CN201910785432.0A CN110481578B (en) | 2019-08-23 | 2019-08-23 | Control method of drag reduction system of high-speed train |
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| CN110481578B true CN110481578B (en) | 2020-07-21 |
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| CN114454905B (en) * | 2021-12-23 | 2023-07-04 | 周忠宝 | Train and train drag reduction method for controlling tail vortex drag reduction by utilizing blowing |
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| US2195599A (en) * | 1937-04-19 | 1940-04-02 | Budd Edward G Mfg Co | Vehicle |
| NL8900633A (en) * | 1989-03-15 | 1990-10-01 | Sicommerce Ag | Railway locomotive with movable nose section - is hinged under windscreen allowing simple repair after minor collisions |
| CN103121454B (en) * | 2013-03-05 | 2015-05-20 | 唐山轨道客车有限责任公司 | Railway vehicle telescopic head and railway vehicle |
| CN105313910A (en) * | 2014-08-01 | 2016-02-10 | 郭宏斌 | A high speed train provided with a resistance reducing device |
| KR101743684B1 (en) * | 2015-10-27 | 2017-06-05 | 공주대학교 산학협력단 | Drag reduction system of KTX |
| CN207997862U (en) * | 2018-01-03 | 2018-10-23 | 冯政尧 | A kind of sealing pipeline bullet train system |
| CN208559342U (en) * | 2018-04-18 | 2019-03-01 | 宁波大艾激光科技有限公司 | Air layers reducing resistance system and bullet train |
| CN109278766A (en) * | 2018-09-19 | 2019-01-29 | 同济大学 | A kind of new High speed wheel rail train system |
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