# Influence of Non-Structural Parameters on Dual Parallel Jet Characteristics of Porous Nozzles

^{1}

^{2}

^{*}

## Abstract

**:**

_{sp}= 22 mm and X

_{pp}= 75 mm, respectively, are not changed; and with the increase in the nozzle spacing ratio, the merging points (MPs) on the parallel jet axis are X

_{mp}= 25 mm, 32 mm and 59 mm, respectively. The merging point and the combined point move to a farther distance and the inner deflection angle of the jet is weakened.

## 1. Introduction

## 2. Establishment of the Simulation Model

#### 2.1. Arrangement of the Dual Parallel Jet

#### 2.2. Computational Domain

#### 2.3. Governing Equations

_{2}is a mixing function which constrains the wall layer as a limit number when the free shear flow does not coincide with the assumption. S is a fixed estimate of the strain rate. a = 0.031 is a constant. The biggest advantage of using the SST model in this paper is that the turbulent shear stress is considered, and the fluid separation at the beginning of flow and negative pressure gradient can be accurately predicted in order to ensure that the eddy viscosity is not over-predicted.

#### 2.4. Boundary Conditions

## 3. Simulation Results

#### 3.1. Process of the Dual Parallel Jet with Porous Nozzles

#### 3.2. Influence of Inlet Pressure on Parallel Jet Characteristics

#### 3.3. Influence of the Nozzle Spacing Ratio on the Characteristics of the Parallel Jet

## 4. Experimental Result and Discussion

_{pp}and d/w by linear regression, and the peak point X

_{pp}can be forecasted through the equation. The equation is as follows:

_{pp}are as shown in Table 4. The errors between the average value and the theoretical value are 0.38%, 1.07% and 4.70%, respectively.

## 5. Conclusions

_{mp}= 22 mm, X

_{cp}= 75 mm; the pressure starting point (SP) and the peak point (PP) are maintained, always at X

_{sp}= 22 mm and X

_{pp}= 75 mm. The pressure and velocity flow fields are consistent.

_{sp}= 27 mm, 38 mm and 69 mm, respectively, and the peak points PP are X

_{pp}= 80 mm, 102 mm and 132 mm, respectively. The two parallel jets merge further away from the jet outlet, and the pressure-boosting region and -reducing region also move further away from the outlet correspondingly.

## Author Contributions

## Funding

## Conflicts of Interest

## References

- Hnaien, N.; Aissia, H.B.; Marzouk, S. Interaction of two plane parallel jet. In Proceedings of the 2015 World Symposium on Mechatronics Engineering & Applied Physics (WSMEAP), Sousse, Tunisia, 11–13 June 2015. [Google Scholar]
- Yu, Y.Q.; Merzari, E.; Thomas, J.W.; Obabko, A.; Aithal, S.M. Steady and unsteady calculations on thermal striping phenomena in triple-parallel jet. Nucl. Eng. Des.
**2016**, 312, 429–437. [Google Scholar] [CrossRef] [Green Version] - Miles, J.; Miles, J. Wave Number Selection for Incompressible Parallel Jet Flows Periodic in Space. In Proceedings of the 28th Fluid Dynamics Conference, Snowmass Village, CO, USA, 29 June–2 July 1997. [Google Scholar]
- Cheong, K.-P.; Wang, G.; Wang, B.; Zhu, R.; Ren, W.; Mi, J. Stability and emission characteristics of nonpremixed MILD combustion from a parallel-jet burner in a cylindrical furnace. Energy
**2019**, 170, 1181–1190. [Google Scholar] [CrossRef] - Afsar, M.; Sescu, A.; Sassanis, V. Effect of non-parallel mean flow on the acoustic spectrum of heated supersonic jets: Explanation of ‘jet quietening’. Phys. Fluids
**2019**, 31, 105107. [Google Scholar] [CrossRef] - Fan, G.; Chen, X.; Saxena, K.K.; Liu, J.; Guo, Z. Jet Electrochemical Micromachining of Micro-Grooves with Conductive-Masked Porous Cathode. Micromachines
**2020**, 11, 557. [Google Scholar] [CrossRef] - Cameron, T.; Naseri, E.; MacCallum, B.; Ahmadi, A. Development of a Disposable Single-Nozzle Printhead for 3D Bioprinting of Continuous Multi-Material Constructs. Micromachines
**2020**, 11, 459. [Google Scholar] [CrossRef] - Bezerra, W.D.S.; Castelo, A.; Afonso, A.M. Numerical Study of Electro-Osmotic Fluid Flow and Vortex Formation. Micromachines
**2019**, 10, 796. [Google Scholar] [CrossRef] [PubMed] [Green Version] - Xiang, H.; Xiaolong, L.; Hang, J.; Siying, L.; Zhenxiang, B.; Gonghan, H.; Daoheng, S.; Lingyun, W. Effect of Enhanced Squeezing Needle Structure on the Jetting Performance of a Piezostack-Driven Dispenser. Micromachines
**2019**, 10, 850. [Google Scholar] - Li, D.; Xu, J.; Rong, W.; Yang, L. Simulation of Picking Up Metal Microcomponents Based on Electrochemistry. Micromachines
**2019**, 11, 33. [Google Scholar] [CrossRef] [Green Version] - Liu, P.; Zhang, H.; Wu, Y.; Zhang, M.; Lu, J. Experimental study on the flow interaction of two parallel rectangular jets through exits with sudden contraction. Exp. Therm. Fluid Sci.
**2017**, 88, 622–631. [Google Scholar] [CrossRef] - Ashok Kumar, M.; Prasad, B.V.S.S.S. Computational Investigations of Flow and Heat Transfer on an Effused Concave Surface with a Single Row of Impinging Jets for Different exit Configurations. Eng. Appl. Comput. Fluid Mech.
**2009**, 3, 530–542. [Google Scholar] - Li, W. Research on Influence of Operating Parameter on Flow Field of Micro-bubble Generator. Coal Prep. Technol.
**2010**, 1, 3. [Google Scholar] - Qian, J.Y.; Chen, M.R.; Liu, X.L.; Jin, Z.J. A numerical investigation of the flow of nanofluids through a micro Tesla valver. J. Zhejiang Univ. Sci. A (Appl. Phys. Eng.)
**2019**, 20, 50–60. [Google Scholar] - Qian, J.Y.; Hou, C.W.; Li, X.J.; Jin, Z.J. Actuation Mechanism of Microvalves: A Review. Micromachines
**2020**, 11, 172. [Google Scholar] [CrossRef] [PubMed] [Green Version] - Evans, G.M.; Rigby, G.D.; Honeyands, T.A.; He, Q.L. Gas dispersion through porous nozzles into down-flowing liquids. Chem. Eng. Sci.
**1999**, 54, 4861–4867. [Google Scholar] [CrossRef] - Okada, O.; Fujita, H. Behavior of liquid films and droplets in the non-equilibrium region of a downward annular mist flow (comparison of porous and central nozzle mixing methods). Int. J. Multiph. Flow
**1993**, 19, 79–89. [Google Scholar] [CrossRef] - Ali, S.A.S.; Azarpeyvand, M.; da Silva, C.R.I. Trailing edge bluntness noise reduction using porous treatments. J. Sound Vib.
**2020**, 474, 115257. [Google Scholar] - Wei, M.; Wu, C.; Zhou, Y. Numerical Simulation and Experimental Study on Flow of Polymer Aqueous Solution in Porous Jet Nozzle. Adv. Polym. Technol.
**2020**, 2020, 1–9. [Google Scholar] [CrossRef] - Fujisawa, N.; Nakamura, K.; Srinivas, K. Interaction of two parallel plane jets of different velocities. J. Vis.
**2004**, 7, 135–142. [Google Scholar] [CrossRef] - Khazaei, J.; Ekrami-Rad, N.; Safa, M.; Nosrati, S.Z. Effect of air-jet impingement parameters on the extraction of pomegranate arils. Biosyst. Eng.
**2008**, 100, 214–226. [Google Scholar] - Tian, S.; He, Z.; Li, G.; Wang, H.; Shen, Z.; Liu, Q. Influences of ambient pressure and nozzle-to-target distance on SC-CO
_{2}jet impingement and perforation. J. Nat. Gas Sci. Eng.**2016**, 29, 232–242. [Google Scholar] [CrossRef] - Assoudi, A.; Habli, S.; Saïd, N.M.; Bournot, H.; Palec, G.L. Experimental and numerical study of an offset jet with different velocity and offset ratios. Eng. Appl. Comput. Fluid Mech.
**2015**, 9, 490–512. [Google Scholar] [CrossRef] [Green Version] - Chandran, K.; Banerjee, I.; Padmakumar, G.; Reddy, K.S. Numerical Analysis of Thermal Striping Phenomena Using a Two Jet Water Model. Eng. Appl. Comput. Fluid Mech.
**2010**, 4, 209–221. [Google Scholar] - Wang, X.D.; Li, Z.; Liang, J.Y.; Kang, S. Numerical Simulations of Imperfect Bifurcation of Jet in Crossflow. Eng. Appl. Comput. Fluid Mech.
**2012**, 6, 595–607. [Google Scholar] - Kwon, B.; Foulkes, T.; Yang, T.; Miljkovic, N.; King, W.P. Air Jet Impingement Cooling of Electronic Devices Using Additively Manufactured Nozzles. IEEE Trans. Compon. Packag. Manuf. Technol.
**2020**, 10, 220–229. [Google Scholar] [CrossRef] - Wang, X.K.; Tan, S.K. Experimental investigation of the interaction between a plane wall jet and a parallel offset jet. Exp. Fluids
**2007**, 42, 551–562. [Google Scholar] [CrossRef] - Mondal, T.; Das, M.K.; Guha, A. Periodic vortex shedding phenomenon for various separation distances between two plane turbulent parallel jets. Int. J. Heat Mass Transf.
**2016**, 99, 576–588. [Google Scholar] [CrossRef] - Zhao, L.-Q.; Wang, X.-C. Numerical investigation of parallel plane jets at low Reynolds number. Eur. J. Mech. B Fluids
**2018**, 67, 211–219. [Google Scholar] [CrossRef] - Manigandan, S.; Vijayaraja, K.; Gunasekar, P.; Nithya, S.; Devipriya, J.; Ilangovan, N. Mixing characteristics of elliptical throat sonic jets from orifice and nozzle. Int. J. Ambient Energy
**2019**, 40, 393–395. [Google Scholar] [CrossRef] - Behrouzi, P.; McGuirk, J.J. Laser Doppler velocimetry measurements of twin-jet impingement flow for validation of computational models. Opt. Lasers Eng.
**1998**, 30, 265–277. [Google Scholar] [CrossRef] - Tanaka, E. The Interference of Two-Dimensional Parallel Jets: 1st Report Experiments on Dual Jet. Trans. Jpn. Soc. Mech. Eng.
**1969**, 35, 1257–1264. [Google Scholar] [CrossRef] [Green Version] - Tanaka, E. The Interference of Two-Dimensional Parallel Jets: 2nd Report, Experiments on the Combined Flow of Dual Jet. Jpn. Soc. Mech. Eng.
**1974**, 17, 920–927. [Google Scholar] [CrossRef] - Tanaka, E.; Nakata, S. The Interference of Two-Dimensional Parallel Jets: 3rd Report, The Region near the Nozzles in Triple Jets. Jpn. Soc. Mech. Eng.
**1975**, 18, 1134–1141. [Google Scholar] [CrossRef] - Wang, H.; Lee, S.; Hassan, Y.A. Particle image velocimetry measurements of the flow in the converging region of two parallel jets. Nucl. Eng. Des.
**2016**, 306, 89–97. [Google Scholar] [CrossRef] [Green Version] - Krothapalli, A.; Baganoff, D.; Karamcheti, K. On the mixing of a rectangular jet. J. Fluid Mech.
**1981**, 107, 201. [Google Scholar] [CrossRef]

**Figure 6.**Symmetry plane 2 contours of the first confluence: (

**a**) velocity contour; (

**b**) pressure contour.

**Figure 7.**Symmetry plane 2 contours of the secondary confluence: (

**a**) velocity contour; (

**b**) pressure contour.

**Figure 8.**Symmetry plane 2 velocity contours with different inlet pressures: (

**a**) velocity contour; (

**b**) pressure contour.

**Figure 9.**Symmetry plane 2 contours with different nozzle spacing ratios: (

**a**) velocity contours; (

**b**) pressure contours.

Parameter | Value |
---|---|

diameter of the jet port D_{1} | 1 mm |

internal diameter of the nozzle pipe D_{2} | 9 mm |

nominal diameter of the thread D_{3} | 13 mm |

height of the sector boss H_{1} | 2 mm |

Height of the hexagon H_{2} | 8 mm |

distance between the opposite sides of the hexagon H_{3} | 14 mm |

distance between the opposite jet holes w | 6 mm |

distance between the two nozzle axes d | 18/24/30 mm |

Parameter | Value |
---|---|

medium | Constant air |

pressure inlet | 0.1/0.3/0.5 MPa |

pressure outlets | 0 Mpa |

symmetrical plane | Symmetry |

other boundaries | Wall |

Parameter | Value |
---|---|

range | 0–±8000 Pa |

accuracy class | 0.5 FS |

operation temperature | 25 °C |

Spacing Ratio d/w | Theoretical Value | Average Value | Error |
---|---|---|---|

3 | 80.3 mm | 80 mm | 0.38% |

4 | 103.1 mm | 102 mm | 1.07% |

5 | 125.8 mm | 132 mm | 4.70% |

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**MDPI and ACS Style**

Zhang, J.; Lv, R.; Yang, Q.; Liu, B.; Li, Y.
Influence of Non-Structural Parameters on Dual Parallel Jet Characteristics of Porous Nozzles. *Micromachines* **2020**, *11*, 772.
https://doi.org/10.3390/mi11080772

**AMA Style**

Zhang J, Lv R, Yang Q, Liu B, Li Y.
Influence of Non-Structural Parameters on Dual Parallel Jet Characteristics of Porous Nozzles. *Micromachines*. 2020; 11(8):772.
https://doi.org/10.3390/mi11080772

**Chicago/Turabian Style**

Zhang, Jin, Ruiqi Lv, Qifan Yang, Baolei Liu, and Ying Li.
2020. "Influence of Non-Structural Parameters on Dual Parallel Jet Characteristics of Porous Nozzles" *Micromachines* 11, no. 8: 772.
https://doi.org/10.3390/mi11080772