Pressure probe adopting single-row-hole air film cooling
Technical Field
The invention relates to the technical field of high-temperature flow field testing, in particular to a pressure probe cooled by a single-row-hole air film, which can prevent the probe from being damaged by high-temperature incoming flow in the high-temperature flow field testing.
Background
In experiments or industrial production, pressure in a high-temperature flow field is often required to be measured, however, a common pressure probe has no cooling device, and if the high-temperature flow field is directly measured, the probe is often deformed or even broken due to too high temperature. In order to increase the temperature that the probe can withstand, cooling protection must be provided. Compared with various cooling methods developed at present, the research on the air cooling direction is more, and the research mainly comprises convection cooling, impingement cooling, column rib cooling and the like, and air film cooling and the like. The probe used for the high-temperature flow field test is reasonably cooled and designed, so that the probe can be prevented from being damaged by high temperature, and the test task is completed.
Disclosure of Invention
The invention mainly solves the technical problem of providing a pressure probe cooled by a single-row-hole air film, which can reduce the temperature of the probe through an air film cooling technology, and can effectively protect the probe through the air film when the incoming flow direction is more stable, thereby realizing the measurement in a high-temperature flow field.
In order to solve the technical problems, the invention adopts a technical scheme that:
there is provided a pressure probe cooled by a single row of holes film, comprising: probe head, branch, pressure tube, air film hole, changeover portion, intake pipe. The probe head is welded with the supporting rod, the number of the pressure guiding pipes corresponds to the number of the holes in the probe head, one end of each pressure guiding pipe is arranged at the pressure measuring hole in the probe head, and the other end of each pressure guiding pipe penetrates through the supporting rod and extends out of the hole in the switching section.
Further, a gas film hole is processed on the surface of the support rod, low-temperature gas is sent into the support rod through the gas inlet pipe, the low-temperature gas is blown out of the gas film hole and attached to the surface of the support rod under the action of incoming flow, and therefore the low-temperature gas film is formed and the probe is prevented from being damaged by high-temperature incoming flow.
Furthermore, the air inlet pipe needs to adjust the flow and the temperature of the cooling air sent into the support rod according to the main flow and the temperature, so that the proper air blowing ratio and temperature ratio are kept.
Further, the pressure probe head has an outer diameter of 4 to 8 mm and a length of 10 to 15 mm.
Furthermore, the included angle between the axis of the air film hole and the dead point on the probe supporting rod is +/-10 degrees to +/-45 degrees, and the hole is a circular hole with the diameter of 0.5 to 1 mm.
Furthermore, the included angle between the axis direction of the air film holes and the axis direction of the supporting rod is 30 degrees to 60 degrees, the distance between the air film holes and the two ends of the supporting rod are 1.5 millimeters to 5 millimeters, the air film holes are coordinated with the hole diameter, and the distance ratio is ensured to be 3 to 5.
Furthermore, the inner diameter of the supporting rod is 2-5 mm, the wall thickness is 1.5-4 mm, and the length-diameter ratio is ensured to be 3-5 according to the coordination of the aperture and the included angle between the axis direction of the air film hole and the axis direction of the supporting rod.
Furthermore, the air inlet pipe is adjusted according to the main flow, and the air blowing ratio of the air film hole is ensured to be 0.4-1.5.
Further, the air inlet pipe adjusts the temperature of the cooling air according to the temperature of the main flow, and the ratio of the temperature of the cooling air flow to the temperature of the main flow is guaranteed to be 0.4-1.
The invention has the beneficial effects that: the invention forms a cooling air film on the surface of the pressure probe on the basis of internal cooling of the pressure probe, and directly transfers heat between high-temperature airflow and the surface of the probe in an area covered by the air film to form a three-temperature heat transfer system of the high-temperature airflow, the cooling air film and the surface of the probe. Meanwhile, the jet flow and the temperature of cooling air flow are adjusted according to the flow and the temperature of incoming flow, the cooling efficiency is ensured, and the probe damage caused by high temperature in a high-temperature flow field test is prevented.
Drawings
FIG. 1 is a schematic diagram of a preferred embodiment of a pressure probe employing single row hole film cooling;
FIG. 2 is a cross-sectional view of a pressure probe film hole with single row hole film cooling;
the parts in the drawings are numbered as follows: 1. a probe head; 2. a strut; 3. a pressure guiding pipe; 4. a gas film hole; 5. a switching section; 6. an air inlet pipe.
Detailed Description
The following detailed description of the preferred embodiments of the present invention, taken in conjunction with the accompanying drawings, will make the advantages and features of the invention easier to understand by those skilled in the art, and thus will clearly and clearly define the scope of the invention.
As shown in fig. 1, a pressure probe employing single row hole film cooling, comprising: the probe comprises a probe head (1), a support rod (2), a pressure leading pipe (3), a gas film hole (4), a switching section (5) and an air inlet pipe (6). The probe head (1) is welded with the supporting rod (2), the number of the pressure guiding pipes (3) corresponds to the number of the holes on the probe head (1), one end of each pressure guiding pipe is arranged at the pressure measuring hole on the probe head (1), and the other end of each pressure guiding pipe penetrates through the supporting rod (2) and extends out of the hole on the switching section (5).
The probe head (1) has an outer diameter of 4 mm and a length of 12 mm. An air film hole (4) is formed at the position of +/-15 degrees between the probe supporting rod (2) and a stagnation point, and the hole is a circular hole with the diameter of 0.6 mm. The included angle between the axial direction of the air film holes (4) and the axial direction of the supporting rod (2) is 30 degrees, and the distance between the air film holes is 2.4 millimeters. The inner diameter of the support rod (2) is 5 mm, the wall thickness is 1.5 mm, and the length is 50 mm.
The pressure probe adopting single-row-hole air film cooling introduced by the embodiment has the advantages that the air film hole distance ratio is 4 by reasonably selecting the parameters of the air film holes, the length-diameter ratio is about 3.8, the cooling efficiency is better, when the flow field is actually measured, the jet flow and the temperature are adjusted according to the main flow parameters, the cooling efficiency of the low-temperature air film is ensured, the probe is prevented from being damaged by high-temperature incoming flow, the head of the probe is avoided by the air film, the interference of jet flow on measurement is avoided, and the probe can be stably and continuously measured in the high-temperature flow field.
The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.