CN-122015985-A - Grid type three-dimensional pitot tube flue gas flow testing system and method

CN122015985ACN 122015985 ACN122015985 ACN 122015985ACN-122015985-A

Abstract

The invention discloses a grid type three-dimensional pitot tube flue gas flow testing system and method. Aiming at the problems of uneven large-section complex flue flow field and irregular streamline, the flue section is divided into a plurality of grids, three-dimensional pitot tubes are arranged in the center of the grids, meanwhile, a plurality of grids are set into a partition in a partition patrol mode, the plurality of grids in each partition carry out the patrol measurement, and the multi-point flow field measurement is completed by using a limited number of pressure transmitters. And fitting and integrating the acquired multidimensional flow velocity and static pressure data through a processing unit to obtain the overall flow of the flue gas. The invention can obviously improve the accuracy of measuring the flue gas flow with large cross section, simultaneously reduces equipment investment, and is particularly suitable for the scenes needing high-accuracy flow field monitoring such as carbon dioxide emission measurement and the like.

Inventors

WANG HUIQING
WANG WENLONG
Tian Zishuo
ZHAO YUANCAI
QIAO BOTAO
ZHANG PUXUAN
MENG YONG
WANG YUAN
FENG BIN
LU JIAQI

Assignees

西安热工研究院有限公司

Dates

Publication Date: 20260512
Application Date: 20260331

Claims (10)

1. A grid three-dimensional pitot tube flue gas flow test system, comprising: the grid dividing unit is used for dividing the section of the large-section flue into a plurality of regular grids; The three-dimensional pitot tube array is arranged at the center of the grid; the subarea patrol module is used for dividing a plurality of adjacent grids into subareas, and the three-dimensional pitot tubes in the subareas are sequentially switched to the measuring channel through the controller; the data transmission pipeline is used for connecting the three-dimensional pitot tube and the pressure transmitter; and the data acquisition and processing unit is used for receiving and processing the signals output by the pressure transmitter.
2. The grid three-dimensional pitot tube flue gas flow test system of claim 1 wherein the three-dimensional pitot tube is a seven-hole probe.
3. The grid three-dimensional pitot tube flue gas flow test system of claim 1 wherein the grid is a 1m x 1m square grid.
4. The grid three-dimensional pitot tube flue gas flow test system of claim 1, wherein when the flue cross section is irregularly shaped, invalid regions are eliminated by boundary clipping.
5. A grid three-dimensional pitot tube flue gas flow test system according to claim 1 wherein the large section flue grid division is combined into a single partition with a grid of 3m x 4 m.
6. The grid type three-dimensional pitot tube flue gas flow test system according to claim 1, wherein the partitioned patrol module comprises a controller and a partitioned control program, the controller controls the three-dimensional pitot tubes in the partitions to be sequentially switched, and the partitioned control program sets patrol sequence and time parameters.
7. The grid type three-dimensional pitot tube flue gas flow testing system according to claim 1, wherein the data acquisition and processing unit comprises a data preprocessing module, a data calculation module and a result output module, wherein the data preprocessing module is used for performing filtering, denoising and outlier correction, the data calculation module is used for calculating a section flow field by adopting a fitting, interpolation or integration algorithm, and the result output module is used for outputting flow velocity and flow results.
8. The grid three-dimensional pitot tube flue gas flow test system of claim 1, wherein the data transmission line is comprised of a high temperature, corrosion resistant tubing.
9. The grid three-dimensional pitot tube flue gas flow test system of claim 8, wherein the data transfer line is provided with purge and drain interfaces.
10. A method of grid three-dimensional pitot tube flue gas flow measurement, characterized in that the method is based on a grid three-dimensional pitot tube flue gas flow measurement system according to any of claims 1 to 9, comprising the steps of: Step 1, a grid model is established according to the section size of a flue, and a three-dimensional pitot tube is arranged in the center of the grid; Step 2, setting a partition scheme, and dividing a plurality of grids into a plurality of partitions; Step 3, sequentially switching the three-dimensional pitot tubes in the subareas through a controller, and collecting a speed component and a static pressure signal; Step 4, judging whether the partition data is acquired completely, continuing to patrol when the partition data is not acquired completely, and entering the next step when the partition data is acquired completely; Step 5, inputting the partitioned measurement data into a data acquisition and processing unit, and carrying out pretreatment and numerical calculation to obtain flow field distribution of the section of the flue; And 6, carrying out integral operation on the convection field to obtain the section average flow velocity and the whole flue gas flow.

Description

Grid type three-dimensional pitot tube flue gas flow testing system and method Technical Field The invention belongs to the technical field of industrial flue gas flow measurement, and particularly relates to a grid type three-dimensional pitot tube flue gas flow test system and method. Background In the industrial production process, the accurate measurement of the smoke emission is of great significance to energy conservation and emission reduction, emission accounting and carbon transaction. Conventional flue gas flow measurement methods include single-hole pitot tubes, multi-hole sampling probes, ultrasonic flow meters, and the like. The pitot tube measurement is widely applied due to simple structure and high reliability, but has the following defects in a large-section complex flue: 1. the measurement accuracy is insufficient, the flow velocity distribution of the section of the flue is uneven, and a single point or a small number of sampling points are difficult to represent the whole flow; 2. The adaptability is poor, the smoke streamline is often in three-dimensional irregular distribution, and the traditional pitot tube can only measure unidirectional speed and can not reflect the complete flow field; 3. the system has high cost, and if the full-section multipoint arrangement is adopted and the measurement is carried out simultaneously, a large number of pressure transmitters and acquisition channels are needed, and the equipment cost and the maintenance amount are obviously increased. Therefore, a flue gas flow testing method and a flue gas flow testing system which are compatible with measurement accuracy and system economy are urgently needed to meet high-accuracy requirement scenes such as carbon emission monitoring. The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person of ordinary skill in the art. Disclosure of Invention The invention aims to provide a grid type three-dimensional pitot tube flue gas flow testing system and method for solving the problems of insufficient precision, poor flow field adaptability, high hardware cost and the like of flue gas flow measurement for a large-section complex flue in the prior art. According to the invention, based on the technical characteristics defined in the claims, the three-dimensional pitot tube array is arranged in the center of the cross-section grid, the partitioned patrol control is adopted, and the signal transmission and the numerical reconstruction algorithm are combined, so that the high-precision coverage and measurement of the complex three-dimensional flow field are realized, and the consumption of expensive hardware such as a pressure transmitter in a system is obviously reduced. In order to achieve the above purpose, the present invention adopts the following technical scheme: A grid three-dimensional pitot tube flue gas flow measurement system comprising: the grid dividing unit is used for dividing the section of the large-section flue into a plurality of regular grids; The three-dimensional pitot tube array is arranged at the center of the grid; the subarea patrol module is used for dividing a plurality of adjacent grids into subareas, and the three-dimensional pitot tubes in the subareas are sequentially switched to the measuring channel through the controller; the data transmission pipeline is used for connecting the three-dimensional pitot tube and the pressure transmitter; and the data acquisition and processing unit is used for receiving and processing the signals output by the pressure transmitter. The invention is further improved in that the three-dimensional pitot tube is a seven-hole probe. The invention is further improved in that the grid is a square grid of 1m x 1 m. The invention further improves that when the section of the flue is in an irregular shape, invalid areas are removed by a boundary cutting method. A further improvement of the invention is that the large-section flue grid division is combined into a partition by a grid of 3m multiplied by 4 m. The invention further improves that the subarea patrol module comprises a controller and a subarea control program, wherein the controller controls the three-dimensional pitot tubes in the subareas to be sequentially switched, and the subarea control program sets patrol sequence and time parameters. The invention further improves that the data acquisition and processing unit comprises a data preprocessing module for executing filtering, denoising and abnormal value correction, a data calculation module for calculating the section flow field by adopting fitting, interpolation or integration algorithm, and a result output module for outputting flow velocity and flow result. A further development of the invention is that the data transmission line con