CN213397634U

CN213397634U - Engine exhaust pressure measuring device

Info

Publication number: CN213397634U
Application number: CN202022655877.8U
Authority: CN
Inventors: 张佛成; 李彩俊
Original assignee: Shanghai Volvo Automobile Research And Development Co ltd
Current assignee: Shanghai Volvo Automobile Research And Development Co ltd
Priority date: 2020-11-17
Filing date: 2020-11-17
Publication date: 2021-06-08
Anticipated expiration: 2030-11-17

Abstract

The present application relates to an engine exhaust pressure measurement device. The apparatus for engine exhaust pressure measurement comprises: a pressure sensor; a liquid trap connected to the pressure sensor, the liquid trap comprising a housing defining an internal cavity and first and second ports mounted to the housing, the second port constituting a port for receiving an exhaust gas flow to be measured by an engine exhaust pressure measuring device and the second port, the internal cavity and the first port constituting an exhaust gas flow delivery path to the pressure sensor, wherein the first and second ports are spaced apart away from a bottom of the housing.

Description

Engine exhaust pressure measuring device

Technical Field

The present application relates generally to the field of engine measurement, and more particularly to engine exhaust pressure measurement devices.

Background

Exhaust pressure of a vehicle engine is an important indicator that affects the performance and operation of the vehicle engine. In the engine development and test stage and the factory inspection process, measurement of the exhaust pressure of the engine is widely involved. In order to facilitate the arrangement of a plurality of devices such as sampling, measuring, analyzing and controlling in a limited test space, a tiny flexible sampling pipe is often used for communicating a sensor and a sampling site in practice. However, for long duration measurements, condensation is likely to form in the tube, which can accumulate at low potential levels in the tube and even clog the fine sampling tube, adversely affecting the real-time accurate measurement of the sensor. To remove the condensed water from the sample tube, a compressed air sweep may be used to blow the water from the sample tube into the engine exhaust, but this can only be done before or after the test, and the back and forth instrument changing process (e.g., removing the pressure sensor and purging with compressed air, or vice versa) is cumbersome and affects the continuity of the test.

Thus, there is still room for improvement in engine exhaust pressure measurement.

SUMMERY OF THE UTILITY MODEL

The application provides an engine exhaust pressure measuring device, which utilizes entrainment of condensed water in a pipeline by exhaust airflow and a liquid collector which can separate and collect liquid is arranged at the upstream of a pressure sensor, so that accumulated water in the pipeline is gathered at the bottom of the liquid collector far away from a main flow path, thereby preventing measurement path blockage and measurement distortion. The liquid trap is arranged such that water separates from the gas stream in the interior chamber of the liquid trap by its own weight and settles at the bottom of the interior chamber of the liquid trap remote from the gas inlet and gas outlet of the liquid trap. The device has simple structure, easy use, convenient operation, stability and reliability.

According to an aspect of the present application, there is provided an engine exhaust pressure measuring apparatus including: a pressure sensor; a liquid trap connected to the pressure sensor, the liquid trap comprising a housing defining an internal cavity and first and second ports mounted to the housing, the second port constituting a port for receiving an exhaust gas flow to be measured by an engine exhaust pressure measuring device and the second port, the internal cavity and the first port constituting an exhaust gas flow delivery path to the pressure sensor, wherein the first and second ports are spaced apart away from a bottom of the housing.

Optionally, the first and second ports are positioned gravitationally higher than a bottom of the housing.

Optionally, the second port is located between the first port and the bottom of the housing.

Optionally, the first port is defined by a first tubular port extending from a top of the housing, and the first tubular port is oriented in a direction of gravity.

Optionally, the second port is defined by a second tubular port extending from a side of the housing between the bottom and the top, and the second tubular port is oriented horizontally.

Optionally, a selectively operable drain is provided in the bottom of the housing.

Optionally, the drain comprises a valve with an accessible valve opening adjustment.

Optionally, the pressure sensor is positioned gravitationally higher than the first port of the liquid trap.

Optionally, the engine exhaust pressure measuring device further comprises a first hose to connect the first port of the liquid trap with the pressure sensor; and/or a second hose to connect the second port of the accumulator with an engine exhaust line.

Optionally, a mounting bracket is attached to the housing of the liquid trap.

By utilizing the engine exhaust pressure measuring device, the outstanding problem that pipeline water accumulation influences exhaust pressure measurement in the prior art is solved, long-time continuous measurement is allowed, and various tests, experiments and the like related to engine exhaust pressure measurement are greatly facilitated.

Drawings

Together with the following description, the drawings serve to explain the principles of the application. In the drawings:

FIG. 1 is a conceptual schematic diagram illustrating a conceptual illustration of a liquid trap according to the principles of the present application;

FIG. 2 is a diagram illustrating an example of a liquid trap and one possible measurement arrangement associated therewith according to the principles of the present application.

It is to be understood that the drawings are solely for purposes of illustration and are not intended as a definition of the limits of the application. The dimensions of some of the features may be arbitrarily expanded or reduced for clarity.

Detailed Description

Embodiments of the present application are described below with reference to the drawings. The description is only for the purpose of enabling those skilled in the art to readily understand the present application, and is not intended to limit the scope of the present application in any way.

Spatially relative terms such as "upper," "lower," "top," "bottom," "side," and the like are used in this application for ease of description only to describe the spatial relationship of one element/feature relative to another element/feature as illustrated in the figures. It is understood that this application is intended to cover other orientations of the device prior to assembly, in use, etc., in addition to the orientation depicted in the figures.

As used herein, "upstream" and "downstream" are with respect to the flow path of the sampled gas stream in the engine exhaust from the sampling point to the pressure sensor. Accordingly, a first element/feature upstream of a second element/feature refers to: in the flow path from the sampling point to the pressure sensor, the sampled airflow passes through the first element/feature and then through the second element/feature. Similarly, a first element/feature downstream from a second element/feature refers to: in the flow path from the sampling point to the pressure sensor, the sampling gas flow passes through the second element/feature and then the first element/feature.

Furthermore, as will be understood by those skilled in the art, references herein to "connected" shall specifically encompass a gas-tight connection to adaptively meet the gas-tight requirements of various specifications for engine exhaust pressure measurements. Additionally, unless otherwise specified herein, the terms "vertical," "horizontal," and the like are with respect to a ground reference frame. Vertically upwards will mean the direction opposite to gravity.

The present application relates generally to an engine exhaust pressure measurement device. The device includes a pressure sensor, a liquid trap in fluid communication with the pressure sensor, and optionally a length of hose for connecting the pressure sensor to the liquid trap.

The pressure sensor according to the present application may be any type of pressure sensor such as a piezoelectric, capacitive, resistive pressure sensor, etc., and may be used to measure the pressure of a higher temperature gas. The higher temperature includes 200 ℃ to 1000 ℃, and preferably 200 ℃ to 600 ℃.

FIG. 1 illustrates a conceptual schematic of a liquid trap 10 according to the present application. As shown in fig. 1, the liquid trap 10 includes a housing 11, a first port 12, a second port 13, and an optional liquid drain 14.

The housing 11 is made of a material capable of withstanding a relatively high pressure, such as 300kPa, for example, stainless steel, and defines an inner chamber 15 for separating and storing condensed water 16. The housing 11 also mounts a first port 12 and a second port 13 which place the internal chamber 15 in fluid communication with upstream and downstream components, respectively. The first port 12 is arranged on top of the housing 10 and is defined by a vertical tubular extension on top of the housing. The vertical tubular extension may serve as an adapter for the housing 11 and the downstream components, and its extension and pipe diameter may be determined according to the circumstances (e.g., the positioning, size, sensing manner, etc. of the pressure sensor to be connected). The vertical orientation of the first port 12 helps to force the gas flow counter-gravitationally away from the liquid trap 10, promoting gravitational separation in the internal chamber 15. The second port 13 is arranged on the side of the housing 11, separately from the first port 12, and is defined by a horizontal tubular extension on the housing side wall. Similarly, the horizontal tubular extension acts as an adapter for the housing 11 and the upstream components, the extension length and the pipe diameter of which can be determined according to the specific circumstances (e.g., the limitations of the test site on the measurement arrangement, the measurement requirements, the measurement specifications, etc.). The horizontal orientation of the second port 13 helps to force the gas flow into the inner cavity 15 in a horizontal direction, in cooperation with the separately and preferably above-located first port 12, to avoid or reduce the gas flow (especially the gas in the gas flow) towards the bottom of the housing 11.

It is noted that references herein and elsewhere in this application to "vertical" and "horizontal" are not limited to precisely 0 and 90 degrees from the direction of gravity, but are allowed for practically acceptable deviations (e.g., + -10%, etc.), as will be understood by those skilled in the art. However, other orientations of the first port 12 and the second port 13, such as an angled orientation, are also possible.

The exhaust gas flow from upstream passes via the second port 13 into the internal chamber 15 of the liquid trap 10 and, with the internal chamber 15, liquid droplets (such as water droplets), particles and the like entrained in the exhaust gas flow are separated from the gas rising in the gas flow by their own weight as the gas flow flows from the second port 13 to the first port 12, settle and collect at the bottom of the internal chamber 15. The separated droplets and particles are collected at the bottom of the inner chamber 15, avoiding the main flow path of the exhaust gas flow from the second port 13 to the first port 12 and thereby avoiding or reducing possible re-entrainment of liquid or particles by the exhaust gas flow. Advantageously, the second port 13 is provided between the first port 12 and the bottom of the housing 11, thereby better balancing the liquid trap's function of separating droplets and particles (as described further below) with the function of preventing re-entrainment of separated droplets and particles. It is understood that although the second port 13 is shown in the figures as being approximately vertically equidistant from the first port 12 and the bottom of the housing 11, the second port 13 may be positioned at other locations away from the bottom of the housing 11.

Advantageously, the first port 12 is arranged higher than the second port 13 during exhaust pressure measurement. As shown in fig. 1, the first port 12 is disposed at a position farthest from the second port 13 on the top of the housing 11. Extending the length, particularly the vertical component length, of the flow path of the gas stream from the second port 13 to the first port 12 facilitates more adequate separation of liquid droplets and the like from the gas stream. Preferably, the vertical height of the interior cavity of the liquid trap is greater than its horizontal width. More preferably, the vertical height of the interior cavity of the liquid trap is greater than twice its horizontal width.

Optionally, a liquid drain 14 is provided in the bottom of the housing 11. The liquid discharge 14 may include a removable sealing cap or a mechanically openable and closable valve to selectively regulate or control the discharge of liquid from the interior chamber 15. The provision of the liquid discharge portion 14 eliminates the trouble of the liquid trap needing to be detached from the upstream and/or downstream components for discharging the liquid, promoting a reduction in the measurement preparation time. By way of example, a window made of transparent or translucent material (optionally marked with a scale) may also be provided on the side wall of the housing, adjacent to the bottom, to allow the operator to observe the level of liquid in the housing 11 and to decide whether it is necessary to empty the cavity 15 of liquid before the next measurement run is started.

The liquid trap 10 may be connected with the first port 12 directly to a downstream component (i.e. a pressure sensor) or indirectly via a length of hose to a pressure sensor, depending on the arrangement desired for the measurement. The use of a hose facilitates a more flexible arrangement of the measuring device to adapt to the measuring object, the measuring location, etc. In the case of a hose, it is preferred that the hose connects the liquid trap 10 and the pressure sensor in a relatively straight manner, without sharp reverse bends, which avoids constriction of the lumen caused by bending of the hose and consequent blockage of the airway by liquid.

Figure 2 illustrates an example of a liquid trap and one possible measurement arrangement associated therewith according to the principles of the present application. As shown, the liquid trap is in the form of a hollow tank 100. The canister 100 has a body 101 and a first port 102, a second port 103, a valve 104 and a mounting bracket 109 mounted to the body 101.

The body 101 is radially symmetrical, has an axially varying circular cross-section, and is generally divided from top to bottom into a rounded top section 101a, an equal diameter intermediate section 101b, and a rounded bottom section 101 c. With an exemplary 6mm diameter engine exhaust pressure sampling point hole, the exemplary constant diameter middle section 101b has a diameter of 1-6 cm and the exemplary body 101 has a height of 10-20 cm.

The first tubular fitting 102 'extends vertically upward from the domed section 101a of the main body 101 and is connected to the pressure sensor 107 via a first hose 106-1 such that one end of the first port 102 defined by the first tubular fitting 102' is in fluid communication with the cavity defined by the main body 101 and the other end is in fluid communication with the pressure sensor 107. Preferably, the pressure sensor 107 is arranged above, preferably vertically above (e.g. 30-40 cm directly above the tubular connection 102') the tank 100, such that the first hose 106-1 runs substantially in a vertical direction and droplets or the like formed in the first hose 106-1 may run downstream or even directly fall into the tank 100. In practice, the inventors observed that the first hose 106-1 remained substantially dry due to the presence of the canister 100.

The second port 103 is defined by a second tubular port 103' extending in a generally horizontal direction from the constant diameter intermediate section 101 b. The second tubular port 103' is connected to a sampling site of the engine exhaust line 108 via a second hose 106-2 such that the cavity defined within the body 101 is in fluid communication with the engine exhaust line 108 via the second port 103 and the lumen of the second hose 106-2. It is understood that the sampling points referred to herein and elsewhere in this application include designated measurement locations according to industry specifications, desired measurement locations according to engine test development requirements (e.g., near the outside of an engine cylinder exhaust valve outlet, in the exhaust manifold, any desired location after the exhaust muffler), and the like. The second hose 106-2 is made of a high temperature resistant material (e.g., teflon) and the first hose 106-1, which may be the same or different. Optionally, the second hose 106-2 is more resistant to high temperatures than the first hose 106-1. Further, the second hose 106-2 may be formed by connecting different sections of different materials. The layout of the second hose 106-2 can be flexibly adjusted according to the application environment, and in some embodiments, the length of the second hose 106-2 can be up to 1 m. In addition, as will be understood by those skilled in the art, the first and second hoses 106-1 and 106-2 are detachably connected to the pressure sensor 107, the tank 100, and the engine exhaust line 108, so that the measurement personnel can assemble, disassemble, adjust, maintain, etc., the measurement arrangement composed of the pressure sensor, the liquid trap, etc., as needed.

To facilitate retention of the tank 100, optionally, a mounting bracket 5 may be attached to the constant diameter middle section of the body 101. In the illustrated example, the mounting bracket 5 is in the form of a flat plate with two mounting holes. However, other means/devices that allow the tank 100 to be stably held during the measurement are also contemplated.

A valve 104 is provided at the bottom end of the round bottom section 101c of the main body 101 to control the discharge of the accumulated water stored in the round bottom section 101 c. As shown in fig. 2, the valve 104 is in the form of a faucet with an accessible rotary wrench for adjusting the spool movement/valve opening. The arrangement of the valve 4 provides a convenient way of draining the condensate water formed in the line from the sampling point of the engine exhaust line 108 to the pressure sensor 107, so that no air pump is needed, a significant saving in energy consumption and a saving in preparation time for the measurement is achieved.

The volume defined by the body 101, in addition to providing a space for gas-liquid separation, helps to suppress exhaust pressure pulsation noise caused by transient local pulsations in the gas flow in the conduit, providing additional benefits of mechanical smoothing and filtering the exhaust pressure measurement. In addition, the volume of the body 101 from below the second port 103 allows for the storage of a volume of accumulated water such that the frequency of water discharge using the valve 104 may be weekly, monthly, etc. without having to be performed before each measurement.

The present application has been described in conjunction with embodiments. Various modifications, alterations, etc. to the embodiments of the disclosure will become apparent to those skilled in the art upon reading the foregoing detailed description. The modifications, substitutions and the like are also intended to be included within the scope and the equivalent scope of the present application as defined by the appended claims without departing from the spirit and scope of the application.

Claims

1. An engine exhaust pressure measuring apparatus characterized by comprising:

a pressure sensor (107);

a liquid trap (10, 100) connected to the pressure sensor (107), the liquid trap (10, 100) comprising a housing (11, 101) defining an internal cavity (15) and first (12, 102) and second (13, 103) ports mounted to the housing (11, 101), the second port (13, 103) constituting a port for receiving an exhaust gas flow to be measured by an engine exhaust pressure measuring device, and the second port (13, 103), the internal cavity (15) and the first port (12, 102) constituting an exhaust gas flow delivery path to the pressure sensor (107), wherein the first (12, 102) and second (13, 103) ports are separately located away from a bottom (101c) of the housing (11, 101).

2. The engine exhaust pressure measuring device according to claim 1, characterized in that the first port (12, 102) and the second port (13, 103) are located higher in the direction of gravity than the bottom (101c) of the housing (11, 101).

3. The engine exhaust pressure measuring device according to claim 1 or 2, characterized in that the second port (13, 103) is located between the first port (12, 102) and the bottom (101c) of the housing (11, 101).

4. The engine exhaust pressure measurement device according to claim 2, wherein the first port (12, 102) is defined by a first tubular port (102 ') extending from a top portion (101a) of the housing (11, 101), and the first tubular port (102') is oriented in a direction of gravity.

5. The engine exhaust pressure measuring device according to claim 2 or 4, characterized in that the second port (13, 103) is defined by a second tubular interface (103') extending from a side portion between the bottom portion (101c) and the top portion (101a) of the housing (11, 101), and the second tubular interface (103) is horizontally oriented.

6. The engine exhaust pressure measuring device according to claim 1 or 2, characterized in that a selectively operated drain (14, 104) is provided in a bottom portion (101c) of the casing (11, 101).

7. The engine exhaust pressure measuring device of claim 6, wherein the drain (14, 104) includes a valve with an accessible valve opening adjustment.

8. The engine exhaust pressure measuring device according to claim 1 or 2, characterized in that the pressure sensor (107) is located gravitationally higher than the first port (12, 102) of the accumulator (10, 100).

9. The engine exhaust pressure measuring device according to claim 1 or 2, further comprising a first hose (106-1) for connecting the first port (12, 102) of the accumulator (10, 100) with the pressure sensor (107); and/or a second hose (106-2) to connect the second port (13, 103) of the liquid trap (10, 100) with an engine exhaust line (108).

10. The engine exhaust pressure measuring device according to claim 1 or 2, characterized in that a mounting bracket (109) is attached to the casing (11, 101) of the accumulator (10, 100).