后混合磨料空气射流喷嘴结构优化及破煤效果研究

杨恒; 魏建平; 蔡玉波; 张路路; 刘勇

doi:10.12363/issn.1001-1986.22.11.0889

后混合磨料空气射流喷嘴结构优化及破煤效果研究

杨恒^1,,
魏建平^{2, 3},
蔡玉波^{2, 3},
张路路⁴,
刘勇^{2, 3,*, ,}

1.
河南能源集团有限公司，河南郑州 450046
2.
河南理工大学瓦斯地质与瓦斯治理国家重点实验室培育基地，河南焦作 454003
3.
河南理工大学煤炭安全生产与清洁高效利用省部共建协同创新中心，河南焦作 454003
4.
河南城建学院市政与环境工程学院，河南平顶山 467041

基金项目: 国家自然科学基金项目(52174170，52274192)；河南省高校科技创新人才(21HASTIT009)；河南理工大学基本科研业务费专项(NSFRF220205)

详细信息

作者简介:
杨恒，1970年生，男，河南内乡人，博士，教授级高工，从事采矿工程及矿山灾害防治. E-mail：mdskyh@163.com

通讯作者:
刘勇，1984年生，男，山东临沂人，博士，教授，从事射流理论与技术及其在能源开发中应用等方面的研究.E-mail：yoonliu@hpu.edu.cn

中图分类号: TD712
计量
- 文章访问数: 181
- HTML全文浏览量: 23
- PDF下载量: 46
出版历程
- 收稿日期: 2022-11-25
- 修回日期: 2023-01-02
- 录用日期: 2023-02-24
- 网络出版日期: 2023-03-10
- 刊出日期: 2023-02-24

Structure optimization and coal breaking effect of air jet nozzle for post-mixed abrasive

YANG Heng^1,,
WEI Jianping^{2, 3},
CAI Yubo^{2, 3},
ZHANG Lulu⁴,
LIU Yong^{2, 3,*, ,}

1.
Henan Energy Group Limited, Zhengzhou 450046, China
2.
State Key Laboratory Cultivation Base for Gas Geology and Gas Control, Henan Polytechnic University, Jiaozuo 454003, China
3.
State Collaborative Innovation Center of Coal Work Safety and Clean-efficiency Utilization, Henan Polytechnic University, Jiaozuo 454003, China
4.
School of Municipal and Environmental Engineering, Henan University of Urban Construction, Pingdingshan 467041, China

摘要

摘要:
水力化卸压增透技术在煤层瓦斯灾害治理中发挥了重要作用，但在松软煤层中应用时容易导致塌孔、抱钻和喷孔等动力现象。无水化卸压增透是突破松软煤层瓦斯高效抽采技术瓶颈的可行性技术之一。为此，利用磨料空气射流高效破煤岩能力，提出后混合磨料空气射流破煤卸压技术，采用磨料-空气分离输送的双通道方式，将磨料和空气运送至孔底，采用射流泵-拉法尔耦合的后混合喷嘴结构在孔底对磨料进行引射、混合和加速，使磨料具备高冲击动能，实现高效破煤。基于ANSYS-FLUENT气固两相流模型，分析后混合喷嘴内磨料引射、混合和加速规律，研究磨料颗粒在加速过程中的受力，获得混合磨料空气射流高效破煤最优后混合喷嘴结构；并开展后混合磨料气体射流破煤实验验证破煤性能。结果表明：磨料冲击动能决定于后混合喷嘴的引射能力和加速能力。后混合喷嘴的引射能力与引射喷嘴的喷嘴出口直径和其扩张段长度有关，合理的引射喷嘴出口直径有助于减小喷嘴出口气流波动，扩张段长度则会影响喷嘴出口气流速度，在本文条件下，引射喷嘴采用两段式，其中收缩段长度2 mm，喉部直径2 mm，扩张段长度5 mm，喷嘴出口直径为3 mm。加速结构对磨料的加速效果主要取决于加速喷嘴的膨胀比，膨胀比为1的喷嘴内部气流使磨料颗粒所受合力较大，且加速喷嘴外部磨料所受曳力、压力梯度力和虚拟质量力波动范围较小，磨料加速效果明显，在膨胀比为1条件下，设计加速喷嘴收缩管长度4 mm、出口直径7.73 mm、喉管长度40 mm、扩张管长度为15 mm。按照优化后的喷嘴结构进行破煤能力实验，在引射压力为4 MPa，靶距60 cm，磨料质量流量50 g/s，进行冲蚀实验，冲蚀30 s，优化的后混合喷嘴结构对煤块产生了直径约10 cm，深度约5 cm的冲蚀坑，证明了在设计的最优后混合喷嘴结构参数下系统具有较好的破煤效果，具有工程应用的能力。
- 气力化增透 /
- 磨料气体射流 /
- 射流泵 /
- 喷嘴结构优化 /
- 碎软煤层
Abstract:
Hydraulic pressure relief and penetration enhancement technology plays an important role in coal seam gas hozard control, but it is easy to lead to dynamic phenomena such as hole collapse, drill holding and hole spraying during its application in the soft coal seams. Non-hydraulic pressure relief and penetration enhancement is one of the feasible technologies to break through the bottleneck of efficient gas extraction technology in soft coal seams. To this end, the post-mixed abrasive air jet coal breaking and pressure relief technology was proposed with the efficient coal breaking capability of abrasive air jet. Specifically, the abrasive and air are conveyed to the bottomhole by two separate channels, and the post-mixed nozzle structure coupled with jet pump-Laval nozzle is adopted to eject, mix and accelerate the abrasive at the bottomhole, so that the abrasive has high impact kinetic energy to achieve efficient coal breaking. Based on ANSYS-FLUENT gas-solid two-phase flow model, the rule of abrasive ejection, mixing and acceleration in the post-mixing nozzle was analyzed, the force of abrasive particles in the acceleration process was studied, to obtain the optimal post-mixing nozzle structure for efficient coal breaking by mixed abrasive air jet. Besides, post-mixing abrasive gas jet coal breaking experiments were carried out to verify the coal breaking performance. The research results show that the impact kinetic energy of the abrasive is determined by the ejection and acceleration capacity of the post-mixing nozzle. The ejection capacity of the post-mixing nozzle is related to the outlet diameter of the ejecting nozzle and the length of its expansion section. A reasonable outlet diameter of ejection nozzle can help reduce the airflow fluctuation at nozzle outlet, while the length of the expansion section will affect the airflow velocity there. Herein, the two-stage nozzle is adopted, with the contraction section in 2 mm length, the throat in 2 mm diameter, the expansion section in 5 mm length, and the nozzle outlet in a 3 mm diameter. The acceleration effect of the acceleration structure on the abrasive mainly depends on the expansion ratio of the acceleration nozzle. Generally, the internal airflow of the nozzle at an expansion ratio of 1 makes the abrasive particles subjected to a larger resultant force, and the external abrasive of the acceleration nozzle subjected to the traction force, pressure gradient force and virtual mass force with less fluctuation, with obvious abrasive acceleration effect. Conclusively, the acceleration nozzle is designed with a contraction tube with 4 mm length and 7.73 mm outlet diameter, a 40 mm long throat, and a 15 mm long expansion tube at the expansion ratio of 1. On this basis, a coal breaking capacity experiment was conducted with the optimized nozzle structure. Meanwhile, the erosion experiment was carried out at the ejection pressure of 4 MPa, target distance of 60 cm, and abrasive mass flow of 50 g/s. After 30 s of erosion, an erosion pits of about 10 cm in diameter and 5 cm in depth was produced by the optimized post-mixing nozzle structure on the coal blocks. Thus, it is proved that the system has good coal breaking effect with the designed parameters of the optimal post-mixing nozzle structure and has the capability of engineering application.
- pneumatization penetration enhancement /
- abrasive gas jet /
- jet pump /
- nozzle structure optimization /
- crushed soft coal seam

HTML全文

图 1 后混合磨料空气射流系统原理

Fig. 1 Post-mixed abrasive air jet system

下载: 全尺寸图片幻灯片

图 2 后混合磨料空气射流物理模型

l_s1、l_s2、l_s3—引射喷嘴收缩段、喉部和扩张段长度；d_s1、d_s2—引射喷嘴喉部和出口截面直径；l_a1、l_a2、l_a3—加速喷嘴收敛段、喉部和扩张段长度；d_a1、d_a2—加速喷嘴喉部和出口截面直径

Fig. 2 Physical model of post-mixed abrasive air jet

下载: 全尺寸图片幻灯片

图 3 引射喷嘴不同出口直径下钻杆外层和喉部气流速度

Fig. 3 Airflow velocity in the outer layer of drill pipe and throat at different outlet diameters of ejection nozzle

下载: 全尺寸图片幻灯片

图 4 引射喷嘴出口截面外的气体压力

Fig. 4 Gas pressure outside the outlet section of the ejection nozzle

下载: 全尺寸图片幻灯片

图 5 引射喷嘴各阶段对出口气流速度的影响

Fig. 5 Effect of each sections of ejection nozzle sections on outlet gas velocity

下载: 全尺寸图片幻灯片

图 6 喷嘴轴线密度与速度变化

Fig. 6 Nozzle axis density and velocity variation

下载: 全尺寸图片幻灯片

图 7 喷嘴内的磨料运移速度与受力情况

Fig. 7 Migration velocity and force of abrasive in the nozzle

下载: 全尺寸图片幻灯片

图 8 喷嘴外气流与磨料参数

Fig. 8 Air flow and abrasive parameters outside the nozzle

下载: 全尺寸图片幻灯片

图 9 磨料在喷嘴外的受力

Fig. 9 Force of abrasive outside the nozzle

下载: 全尺寸图片幻灯片

图 10 出口磨料和气流速度随收敛段长度变化

Fig. 10 Variation of outlet abrasive and airflow velocity with the length of convergent section

下载: 全尺寸图片幻灯片

图 11 喷嘴各阶段加速能力

Fig. 11 Acceleration capability of nozzle in different sections

下载: 全尺寸图片幻灯片

图 12 不同膨胀比的加速喷嘴结构

Fig. 12 Acceleration nozzle structure with different expansion ratios

下载: 全尺寸图片幻灯片

图 13 不同膨胀比喷管结构的射流速度变化

Fig. 13 Variation of jet velocity of nozzle structures at different expansion ratios

下载: 全尺寸图片幻灯片

图 14 实验系统

Fig. 14 Experimental system

下载: 全尺寸图片幻灯片

图 15 不同膨胀比喷嘴煤样冲蚀坑

Fig. 15 Erosion pits caused by nozzles with different expansion ratios

下载: 全尺寸图片幻灯片

图 16 系统对煤体的冲蚀效果

Fig. 16 Erosion effect of the system on coal

下载: 全尺寸图片幻灯片

表 1 加速喷嘴数值模拟边界条件

Table 1 Numerical simulation boundary conditions of acceleration nozzle

项目	数值
外层钻杆气压/MPa	0.4
内层钻杆气压/MPa	4
磨料平均粒径/mm	0.178
质量流量/(g·s⁻¹)	18
气体黏度/(Pa·s)	17.894 × 10⁻⁶
气体比热容/(J·kg⁻¹·K⁻¹)	1006
气体热导率/(W·m⁻¹·K⁻¹)	0.0242
磨料密度/(kg·m⁻³)	3500
磨料泊松比	0.25
磨料比热容/(J·kg⁻¹·K⁻¹)	880
弹性刚度/(N·m⁻¹)	1000
摩擦因数	0.5

下载: 导出CSV

表 2 引射喷嘴出口直径优选方案

Table 2 Optimum outlet diameters for ejection nozzle

引射喷嘴喉部直径/mm	加速喷嘴喉部直径/mm	外层输运压力/MPa	内层钻杆压力/MPa	引射喷嘴出口直径/mm
2	6	0.4	4	2、3、4、5、6

下载: 导出CSV

表 3 引射喷嘴不同阶段长度优选数值模拟方案

Table 3 Numerical simulation scheme for optimum length of different sections in ejection nozzle

外层输运压力/MPa	内层钻杆压力/MPa	引射喷嘴喉部直径/mm	引射喷嘴出口直径/mm	收敛段长度/mm	喉部长度/mm	扩张段长度/mm
0.4	4	2	2	0~10、15、20	0~10、15、20	0~15、20、25、30
			3	0~10、15、20	0~10、15、20	0~15、20、25、30
			4	0~10、15、20	0~10、15、20	0~15、20、25、30
			5	0~10、15、20	0~10、15、20	0~15、20、25、30
			6	0~10、15、20	0~10、15、20	0~15、20、25、30

下载: 导出CSV

表 4 加速喷嘴膨胀比优选数值模拟方案

Table 4 Numerical simulation scheme for optimal expansion ratio of acceleration nozzle

组别	收敛段长度/mm	喉部长度/mm	扩张段长度/mm	喉部直径/mm	膨胀比	出口直径/mm
1	10	50	40	6	0.5	9.4
2					1	7.73
3					2	6.55

下载: 导出CSV

表 5 收敛段长度对磨料加速影响数值模拟方案

Table 5 Numerical simulation scheme for the effect of convergence length on abrasive acceleration

最优膨胀比	收敛段长度/mm	喉部长度/mm	扩张段长度/mm
1	2、4、6、8、10	50	40

下载: 导出CSV

表 6 喉部长度对磨料加速效果影响数值模拟方案

Table 6 Numerical simulation scheme for the effect of throat length on abrasive acceleration

最优膨胀比	最优收敛段长度/mm	喉部长度/mm	扩张段长度/mm
1	4	10、20、30、40、50	40

下载: 导出CSV

表 7 扩张段长度对磨料加速影响数值模拟方案

Table 7 Numerical simulation scheme for the effect of expansion section length on abrasive acceleration

最优膨胀比	最优收敛段长度/mm	最优喉部长度/mm	扩张段长度/mm
1	4	40	10、20、30、40、50、60、70

下载: 导出CSV

表 8 引射喷嘴各结构参数引射能力试验方案

Table 8 Test scheme for ejection capacity of various structural parameters of ejection nozzle

内层钻杆气压/MPa	外层输运气压/MPa	喷嘴喉部直径/mm	磨料质量流量/(g·s⁻¹)	喉部长度/mm	实验组	收敛段长度/mm	喷嘴出口直径/mm	扩张段长度/mm
4	0.4	2	50	0	①	1、2、3	3	5
					②	2	2、3、4	5
					③	2	3	3、4、5、6

下载: 导出CSV

表 9 喷嘴结构参数

Table 9 Structural parameters of nozzle

结构参数	引射喷嘴	加速喷嘴
结构参数	引射喷嘴	(a)	(b)	(c)
收敛段长度/mm	2	4	4	4
喉部直径/mm	2	6	6	6
喉部长度/mm	0	40	35	42
扩张段长度/mm	5	15	20	13
喷嘴出口直径/mm	3	7.73	9.4	6.55

下载: 导出CSV

表 10 不同引射结构磨料引射量

Table 10 Abrasive ejection flow of different ejection structures

实验时间/s	提供磨料质量流量/(g·s⁻¹)	实验组别	收敛段长度/mm	引射喷嘴出口直径/mm	扩张段长度/mm	引射磨料质量流量/(g·s⁻¹)
30	50	①	1 2 3	3	5	47.21
						48.67
						48.64
		②	2	2	5	45.21
				3		48.74
				4		46.34
		③	2	3	3	45.27
					4	47.56
					5	48.71
					6	48.67

下载: 导出CSV

表 11 不同膨胀比喷嘴靶体的质量损失

Table 11 Mass loss of target caused by nozzles with different expansion ratios

膨胀比	组1	组2	平均值
0.5	31.2	34.6	32.9
1	74.5	68.9	71.7
2	48.6	46.3	47.5

下载: 导出CSV

参考文献(23)

[1]	徐凤银,闫霞,林振盘,等. 我国煤层气高效开发关键技术研究进展与发展方向[J]. 煤田地质与勘探,2022,50(3):1−14. XU Fengyin,YAN Xia,LIN Zhenpan,et al. Research progress and development direction of key technologies for efficient coalbed methane development in China[J]. Coal Geology & Exploration,2022,50(3):1−14.
[2]	孙四清,郑凯歌. 井下高压水射流切割煤层增透效果数值模拟[J]. 煤田地质与勘探,2017,45(2):45−49. SUN Siqing,ZHENG Kaige. Numerical simulation study on permeability enhancement effect of high pressure water cutting coal seam[J]. Coal Geology & Exploration,2017,45(2):45−49.
[3]	卢义玉,黄杉,葛兆龙,等. 我国煤矿水射流卸压增透技术进展与战略思考[J]. 煤炭学报,2022,47(9):3189−3211. LU Yiyu,HUANG Shan,GE Zhaolong,et al. Research progress and strategic thinking of coal mine water jet technology to enhance coal permeability in China[J]. Journal of China Coal Society,2022,47(9):3189−3211.
[4]	王建伟. 松软低透气性煤层水力压裂增透瓦斯抽采技术研究[J]. 矿业安全与环保,2021,48(6):47−52. WANG Jianwei. Research on gas drainage hydraulic fracturing improvement technology for soft and low permeability coal seam[J]. Mining Safety & Environmental Protection,2021,48(6):47−52.
[5]	HUANG Fei,MI Jianyu,LI Dan,et al. Comparative investigation of the damage of coal subjected to pure water jets,ice abrasive water jets and conventional abrasive water jets[J]. Powder Technology,2021,394:909−925. DOI: 10.1016/j.powtec.2021.08.079
[6]	邱德才,武贵生,陈冬冬,等. 复合水力化增透技术在低渗突出煤层瓦斯抽采中的应用[J]. 煤田地质与勘探,2015,43(1):13−16. QIU Decai,WU Guisheng,CHEN Dongdong,et al. Compound–hydraulic technology enhancing permeability in lowly permeable and outburst–prone seam[J]. Coal Geology & Exploration,2015,43(1):13−16.
[7]	王耀锋,何学秋,王恩元,等. 水力化煤层增透技术研究进展及发展趋势[J]. 煤炭学报,2014,39(10):1945−1955. WANG Yaofeng,HE Xueqiu,WANG Enyuan,et al. Research progress and development tendency of the hydraulic technology for increasing the permeability of coal seams[J]. Journal of China Coal Society,2014,39(10):1945−1955.
[8]	虎维岳,李静,王寿全. 瓦斯在煤基多孔介质中运移及煤与瓦斯突出机理[J]. 煤田地质与勘探,2009,37(4):6−8. HU Weiyue,LI Jing,WANG Shouquan. The flowing and outburst mechanism of gas in coal–based pore and fractured medium[J]. Coal Geology & Exploration,2009,37(4):6−8.
[9]	刘勇,崔家玮,魏建平,等. 自激振荡脉冲超临界二氧化碳射流发生机制[J]. 煤炭学报,2022,47(7):2643−2655. LIU Yong,CUI Jiawei,WEI Jianping,et al. Generating mechanism of self–excited oscillation pulsed super–critical carbon dioxide jet[J]. Journal of China Coal Society,2022,47(7):2643−2655.
[10]	LIU Yong,ZHANG Juan,WEI Jianping,et al. Optimum structure of a laval nozzle for an abrasive air jet based on nozzle pressure ratio[J]. Powder Technology,2020,364(3):343−362.
[11]	高杰,王海锋,仇海生. 高压氮气致裂增透实验系统的研发及应用[J]. 煤矿安全,2017,48(8):13−15. GAO Jie,WANG Haifeng,QIU Haisheng. Development and application of testing system of high pressure nitrogen blasting experiment for increasing permeability[J]. Safety in Coal Mines,2017,48(8):13−15.
[12]	刘勇,何岸,魏建平,等. 高压气体射流破煤应力波效应分析[J]. 煤炭学报,2016,41(7):1694−1700. LIU Yong,HE An,WEI Jianping,et al. Analysis of stress wave effect during coal breakage process by high pressure gas jet[J]. Journal of China Coal Society,2016,41(7):1694−1700.
[13]	刘勇,代硕,魏建平,等. 低压磨料空气射流破硬岩规律及特征实验研究[J]. 岩石力学与工程学报,2022,41(6):1172−1182. LIU Yong,DAI Shuo,WEI Jianping,et al. Experimental study on hard rock breaking laws and characteristics by low–pressure abrasive air jet[J]. Chinese Journal of Rock Mechanics and Engineering,2022,41(6):1172−1182.
[14]	HUANG Fei,ZHAO Zhiqi,LI Dan,et al. Investigation of the breaking manifestations of bedded shale impacted by a high–pressure abrasive water jet[J]. Powder Technology,2022,397:117021. DOI: 10.1016/j.powtec.2021.11.065
[15]	卢义玉,李良伟,汤积仁,等. 前混合磨料水射流连续加料系统设计与实验研究[J]. 重庆大学学报,2018,41(8):111−120. LU Yiyu,LI Liangwei,TANG Jiren,et al. Design and experimental research of the continuous feeding system of premixed abrasive water jet[J]. Journal of Chongqing University,2018,41(8):111−120.
[16]	左伟芹,卢义玉,夏彬伟,等. 前混合磨料射流新型连续加砂系统设计与实验[J]. 应用基础与工程科学学报,2013,21(2):328−335. ZUO Weiqin,LU Yiyu,XIA Binwei,et al. System design of continuous feeding abrasive for pre–mixed abrasive jet and its experiment[J]. Journal of Basic Science and Engineering,2013,21(2):328−335.
[17]	张成光,张勇,张飞虎,等. 新型后混合式磨料水射流系统的研制[J]. 机械工程学报,2015,51(5):205−212. DOI: 10.3901/JME.2015.05.205 ZHANG Chengguang,ZHANG Yong,ZHANG Feihu,et al. Development of new entrainment abrasive waterjet system[J]. Journal of Mechanical Engineering,2015,51(5):205−212. DOI: 10.3901/JME.2015.05.205
[18]	李良元,黄威,王锐,等. 后混合式磨料水射流的磨料供给系统[J]. 采矿技术,2013,13(5):47−48. DOI: 10.3969/j.issn.1671-2900.2013.05.015 LI Liangyuan,HUANG Wei,WANG Rui,et al. Abrasive supply system with post–mixed abrasive water jets[J]. Mining Technology,2013,13(5):47−48. DOI: 10.3969/j.issn.1671-2900.2013.05.015
[19]	郭鑫辉, 刘勇, 刘笑天, 等. 一种用于后混式磨料气体射流输送磨料的双层钻杆装置: 202120629218. 9[P]. 2021-11-16.
[20]	张东鑫, 刘勇, 刘笑天, 等. 一种自动精准控制磨料质量流量的磨料供给装置: CN202220208635. 0[P]. 2022-06-14.
[21]	刘勇,李志飞,魏建平,等. 磨料空气射流破煤冲蚀模型研究[J]. 煤炭学报,2020,45(5):1733−1742. LIU Yong,LI Zhifei,WEI Jianping,et al. Erosion model of abrasive air jet used in coal breaking[J]. Journal of China Coal Society,2020,45(5):1733−1742.
[22]	刘勇,魏建平,王登科,等. 磨料气体射流冲蚀磨损岩石特征分析[J]. 煤炭学报,2018,43(11):3033−3041. LIU Yong,WEI Jianping,WANG Dengke,et al. Erosive wear characteristic of rock impacted by abrasive gas jet[J]. Journal of China Coal Society,2018,43(11):3033−3041.
[23]	张娟. 膨胀比对高压磨料气体射流破煤影响规律研究[D]. 焦作: 河南理工大学, 2020. ZHANG Juan. Study on the influence of nozzle pressure ratio on coal breaking by high pressure abrasive air jet[D]. Jiaozuo: Henan Polytechnic University, 2020.

施引文献

资源附件(0)

图(16) / 表(11)

计量

文章访问数: 181
HTML全文浏览量: 23
PDF下载量: 46
被引次数: 0

后混合磨料空气射流喷嘴结构优化及破煤效果研究

作者简介: 杨恒，1970年生，男，河南内乡人，博士，教授级高工，从事采矿工程及矿山灾害防治. E-mail：mdskyh@163.com

通讯作者: 刘勇，1984年生，男，山东临沂人，博士，教授，从事射流理论与技术及其在能源开发中应用等方面的研究.E-mail：yoonliu@hpu.edu.cn

计量

出版历程

Structure optimization and coal breaking effect of air jet nozzle for post-mixed abrasive

计量

出版历程

目录

作者简介:
杨恒，1970年生，男，河南内乡人，博士，教授级高工，从事采矿工程及矿山灾害防治. E-mail：mdskyh@163.com

通讯作者:
刘勇，1984年生，男，山东临沂人，博士，教授，从事射流理论与技术及其在能源开发中应用等方面的研究.E-mail：yoonliu@hpu.edu.cn