CN-116127262-B - Method for measuring and calculating particulate matter blocking probability of circulating element

Abstract

The invention relates to a method for measuring and calculating the blocking probability of particles in a circulating element, which comprises the steps of enabling fuel containing particles to pass through the circulating element from an upstream containing cavity to a downstream containing cavity at a flow velocity V, measuring the volume W 1 of the fuel in the downstream containing cavity after the fuel passes through the time and the particle concentration R 1 ;W 1 ＝W 0 +V*t*π*D 2 /4 in the downstream containing cavity, wherein D is the diameter of the circular section of the throat of the circulating element or the hydraulic diameter of the throat, obtaining the quantity P of the particles contained in the fuel passing through the circulating element through a formula, wherein the formula is P=W 1 *R 1 -W 0 *R 0 , obtaining the throughput A through the formula, wherein the formula is A=P×L/V, L is the throat length of the circulating element, and obtaining the blocking probability E (A) through the formula, wherein the formula is as follows: Wherein i is greater than 0 and is a natural number, m is the minimum agglomeration number of the blocking particles, m= [ D/D ] +1, m is a dimensionless quantity, and D is the particle size or equivalent diameter of the particles.

Inventors

• LIU JING
• HU SHOUXIN
• WANG XIAOCHUN
• LI XUEMING

Assignees

• 中国航发北京航科发动机控制系统科技有限公司

Dates

Publication Date

20260505

Application Date

20221028

Claims (7)

1. 1. A method for measuring the probability of particulate matter blockage of a flow element, the method comprising the steps of: Step 1, constructing a throttle test system, wherein the throttle test system comprises an upstream cavity, a circulating element and a downstream cavity, wherein fuel containing particulate matters is arranged in the upstream cavity, and the fuel can flow to the downstream cavity through the circulating element; obtaining an initial fuel volume W 0 in the downstream cavity and an initial particulate matter concentration R 0 in the downstream cavity; measuring the volume W 1 of the fuel in the downstream cavity after the fuel circulation t time and the particle concentration R 1 ;W 1 =W 0 +V*t*π*D 2 /4 in the downstream cavity, wherein D is the diameter of the circular section of the throat part or the hydraulic diameter of the throat part of the circulation element; Step 3, obtaining the quantity P of particulate matters contained in the fuel oil passing through the circulating element through a formula, wherein the formula is P=W 1 *R 1 -W 0 *R 0 ; Step 4, obtaining throughput A through a formula, wherein the formula is that A=P×L/V, and L is the throat length of the flow element; Step 5, obtaining the blocking probability through a formula The formula is: , Wherein i is 0 and is a natural number, m is the minimum blocking particle agglomeration number, m= [ D/D ] +1, m is a dimensionless quantity, D is the particle size or equivalent diameter of the particles, and m means that the diameter of the circular section of the throat of the circulating element or the hydraulic diameter of the throat is rounded relative to the spatial size multiple of the particles and then added with 1.
2. 2. A method for measuring a probability of clogging of a flow member as set forth in claim 1, wherein the particle diameter or equivalent diameter of the particles is in the range of 50 μm to 1mm.
3. 3. A method for measuring the probability of clogging of a flow element as set forth in claim 1, wherein said flow element is a throttle valve.
4. 4. A method for measuring a probability of clogging of a flow element according to claim 1, wherein the flow element is an element having a variable cross-section flow path.
5. 5. A method for measuring the probability of clogging of a flow element as set forth in claim 1, wherein said particulate matter is a metallic particle or a nonmetallic particle.
6. 6. A method for measuring the probability of clogging of a flow element as set forth in claim 1, wherein said particulate matter is an organic or inorganic substance.
7. 7. A method for measuring the probability of particulate clogging of a flow element as set forth in claim 1 wherein the agglomeration of particulate clogging is electrostatic, van der Waals forces or adhesive bonding.

Description

Method for measuring and calculating particulate matter blocking probability of circulating element Technical Field The invention relates to the technical field of cleanliness control and reliability of an aeroengine fuel control system, relates to estimation of fault probability and anti-pollution design estimation of a circulating element, and particularly relates to a method for measuring and calculating particulate matter blocking probability of the circulating element. Background The fuel oil control device is a key part in an oil supply system of an aeroengine, and supplies fuel oil to the engine according to the command of an electronic controller of the engine, a large number of precisely matched mating parts, electrical accessories and a large number of circulating elements are arranged in the fuel oil system, the components are very sensitive to the cleanliness of the oil, the particulate pollutants in the oil can cause jamming and blockage faults, and the aeroengine can cause flameout faults when serious, so that the cleanliness of the fuel oil needs to be strictly controlled in order to ensure the normal operation of the whole fuel oil system. At present, the main measure is to filter the fuel oil by oil filtration to isolate the particle pollutants in the fuel oil, but because the particle pollutants have certain viscosity, the particle pollutants have certain probability of agglomerating into large particles under the action of static electricity, van der Waals force and the like to cause blocking faults, so that the related blocking probability is further required to be evaluated in the design process of the circulating element, the anti-pollution performance is improved, but the related quantitative evaluation means are lacking at present, and the measuring scale of the anti-pollution design of the circulating element is lacking. Disclosure of Invention The invention aims to obtain the blocking probability of the circulating element, reduce the long-time test cost, and the obtained result can be suitable for screening and evaluating the advantages and disadvantages of the anti-pollution design scheme. The technical scheme of the invention is as follows: provided is a method for measuring the probability of clogging of a flow element, comprising the steps of: Step 1, constructing a throttle test system, wherein the throttle test system comprises an upstream cavity, a circulating element and a downstream cavity, wherein fuel containing particulate matters is arranged in the upstream cavity, and the fuel can flow to the downstream cavity through the circulating element; obtaining an initial fuel volume W 0 in the downstream cavity and an initial particulate matter concentration R 0 in the downstream cavity; Measuring the volume W 1 of the fuel in the downstream cavity after the fuel circulation t time and the particle concentration R 1;W1＝W0+V＊t＊π＊D2/4 in the downstream cavity, wherein D is the diameter of the circular section of the throat part or the hydraulic diameter of the throat part of the circulation element; Step 3, obtaining the quantity P of particulate matters contained in the fuel oil passing through the circulating element through a formula, wherein the formula is P=W 1＊R1－W0＊R0; Step 4, obtaining throughput A through a formula, wherein the formula is that A=P×L/V, and L is the throat length of the flow element; Step 5, obtaining blocking probability E (A) through a formula, wherein the formula is as follows: Wherein i is greater than 0 and is a natural number, m is the minimum agglomeration number of the blocking particles, m= [ D/D ] +1, m is a dimensionless quantity, and D is the particle size or equivalent diameter of the particles. For convenience of description, the meaning of m can be understood as that the diameter of the circular section of the throat or the hydraulic diameter of the throat of the flow element is rounded relative to the spatial size multiple of the particulate matter and then added with 1. Further, if the jam probability is greater than 10 -5, it is suggested to improve the flow-through element design. Further, the particle size or the maximum space size range of the particulate matter is 50 μm-1 mm. Further, the flow element is a throttle valve. Further, the flow element is an element having a variable cross-section flow path. Further, the particulate matter is metal particles or nonmetal particles. Further, the particulate matter is an organic matter or an inorganic matter; further, the agglomeration mode of the particulate matter blockage is static electricity, van der Waals force or bonding. The method has the advantages that the method is an original method for evaluating the blocking probability of the flow element, and before the method is proposed, the flow area of the flow element is often required to be increased in order to prevent blocking, but various design improvement measures are qualitative, quantitative results are not available, blockin