An Experimental Investigation on the Effect of Various Swirl Atomizer Orifice Geometries on the Air Core Diameter

Liquid atomization is a process of changing the liquid into small droplets. There are many applications which are related to liquid atomization including fuel injection in combustion systems and also in agricultural sprays. In pressure swirl atomizer, the liquid is injected into the atomizer through tangential port and a swirling motion is formed inside the swirl chamber. In high strength of swirling motion, an air core will be visible inside the atomizer. The liquid is then discharged from the orifice to form a spray which breaks up the liquid into small droplets. The objective of this research is to investigate the effect of various orifice geometries on the air core diameter. The injection pressure was varied in the range of 2 to 8 bar and water was used as the working fluid. Experiment data shows that the air core diameter increases as the injection pressure increased, regardless the discharge orifice diameter and discharge orifice length. It also found that the air core diameter increases as the discharge orifice length decreases and the discharge orifice diameter increases.

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GAS CORE CHARACTERISTICS OF SWIRL EFFERVESCENT ATOMIZER

Jurnal Teknologi ◽

10.11113/jt.v76.5651 ◽

2015 ◽

Vol 76 (9) ◽

Author(s):

Zulkifli Abdul Ghaffar ◽

Salmiah Kasolang ◽

Ahmad Hussein Abdul Hamid ◽

Diyar I. Ahmed ◽

Khairul Imran Sainan ◽

...

Keyword(s):

High Speed ◽

Spray Angle ◽

Orifice Diameter ◽

Working Fluid ◽

Core Size ◽

Core Diameter ◽

Factors Affecting ◽

Effervescent Atomizer ◽

Core Characteristics ◽

Vane Angle

Swirl effervescent atomizer consists of two atomization mechanisms, effervescent and swirl. For a swirl-related atomizer, the air/gas core diameter was reported to be one of the factors affecting the widening of spray angle. A wider spray angle is important to provide a better spray distribution. The characteristic of gas core in an inside-out swirl effervescent atomizer was investigated as part of the study in understanding the mechanism of this type of atomization. The interaction effects between three independent parameters (i.e. swirl-generating vane angle, gas flowrate and discharge orifice diameter) on the size and characteristics of the gas core were investigated. Water and nitrogen gas were used respectively as the working fluid and atomization gas. The high-speed shadowgraph technique was utilized to record the videos of the gas core structures. The video recordings were converted to image sequences and analyzed using an image processing software. It was concluded that a larger gas core was produced with an increasing vane angle or gas flowrate. The increasing gas flowrate tends to increase the gas core size for all cases of the vane angle. Increasing the orifice diameter tends to increase the gas core size for all cases of the gas flowrate. The interaction between the orifice diameter and swirl-generating vane angle on the size of the gas core was inconclusive.

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EFFECT OF GEOMETRICAL PARAMETERS INTERACTION ON SWIRL EFFERVESCENT ATOMIZER SPRAY ANGLE

Jurnal Teknologi ◽

10.11113/jt.v76.5652 ◽

2015 ◽

Vol 76 (9) ◽

Author(s):

Zulkifli Abdul Ghaffar ◽

Salmiah Kasolang ◽

Ahmad Hussein Abdul Hamid ◽

Ow Chee Sheng ◽

Mimi Azlina Abu Bakar

Keyword(s):

High Speed ◽

Video Camera ◽

Spray Angle ◽

Orifice Diameter ◽

Working Fluid ◽

Geometrical Parameters ◽

High Speed Video Camera ◽

Effervescent Atomizer ◽

Vane Angle ◽

Discharge Orifice

A wider spray angle produced by an atomizer is often required in providing a better spray dispersion. The formation and wideness of the spray angle were reported to be affected by the changes in geometrical parameters. In the present study, the effect of the interaction between two geometrical parameters (swirl-generating vane angle and discharge orifice diameter) on the swirl effervescent atomizer spray angle was studied. A newly-designed swirl effervescent atomizer was developed with 30°, 45° and 60° swirl-generating vane angle and 1.5, 2.0 and 2.5mm discharge orifice diameter. The atomizer performance tests were carried out using water as the working fluid and nitrogen gas as the atomizing agent. High-speed shadowgraph technique was deployed to record the resultant sprays produced. Video recordings, acquired using a high-speed video camera, were converted to a sequence of images for further analysis using image processing software. It was found that geometrical parameters of the newly designed atomizer have a great impact on the formation and characteristics of the spray angle. The combined effect of both swirl-generating vane angle and discharge orifice diameter has produced an increase in the spray angle. The largest spray angle was observed at the largest dimension of both geometries.

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Effect of Dimensionless Numbers on Air Core Diameter of Pressure-Swirl Atomizer

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.899.22 ◽

2020 ◽

Vol 899 ◽

pp. 22-28

Author(s):

Zulkifli Abdul Ghaffar ◽

Salmiah Kasolang ◽

Ahmad Hussein Abdul Hamid ◽

Mohd Syazwan Firdaus Mat Rashid

Keyword(s):

Performance Test ◽

Operating Conditions ◽

Spray Angle ◽

Dimensionless Numbers ◽

Flow Area ◽

Core Diameter ◽

Air Core ◽

Swirl Atomizer ◽

Pressure Swirl ◽

Pressure Swirl Atomizer

Air core is an important parameter in pressure swirl atomizer since formation of air core determines the thickness of the discharged liquid sheet and the effective flow area of nozzle discharge. This consequently will affect the coefficient of discharge and the spray angle. This study conducted for the investigation of the relation between dimensionless numbers on the air core diameter. Dimensionless numbers are helpful aid for the quantification of independent parameters involving atomizer design and operating conditions simultaneously. Reynolds number, Re and orifice-to-swirl chamber diameter ratio, N are the dimensionless numbers selected for this study. Despite of the availability of study on the effect of dimensionless numbers on air core diameter, more study requires especially for smaller N. An experimental test-rig was constructed to conduct the performance test of the atomizer. Acquired images were analyzed using image-processing software. It was found that N has more significant effect on the change of air core diameter compared to Re. However, it is observed that at Re = 40000, N = 0.07 produces almost similar air core diameter with N = 0.25 at Re < 20000. In contrast, with N = 0.5, air core diameter produces are larger even at Re < 20000. Hence, it can be concluded that both Re and N are important parameters in characterizing the air core diameter in pressure-swirl atomizer.

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Spray cone angle and air core diameter of hollow cone swirl rocket injector

IIUM Engineering Journal ◽

10.31436/iiumej.v12i3.66 ◽

2011 ◽

Vol 12 (3) ◽

Cited By ~ 2

Author(s):

Ahmad Hussein Abdul Hamid

Keyword(s):

Cone Angle ◽

Injection Pressure ◽

Combustion Efficiency ◽

Fuel Injector ◽

Hollow Cone ◽

Spray Cone Angle ◽

Core Diameter ◽

Spray Cone ◽

Air Core ◽

Liquid Rocket

ABSTRACT : Fuel injector for liquid rocket is a very critical component since that small difference in its design can dramatically affect the combustion efficiency. The primary function of the injector is to break the fuel up into very small droplets. The smaller droplets are necessary for fast quiet ignition and to establish a flame front close to the injector head, thus shorter combustion chamber is possible to be utilized. This paper presents an experimetal investigation of a mono-propellant hollow cone swirl injector. Several injectors with different configuration were investigated under cold ï¬‚ow test, where water is used as simulation fluid. This investigation reveals that higher injection pressure leads to higher spray cone angle. The effect of injection pressure on spray cone angle is more prominent for injector with least number of tangential ports. Furthermore, it was found that injector with the most number of tangential ports and with the smallest tangential port diameter produces the widest resulting spray. Experimental data also tells that the diameter of an air core that forms inside the swirl chamber is largest for the injector with smallest tangential port diameter and least number of tangential ports.ABSTRAK : Injektor bahan api bagi roket cecair merupakan satu komponen yang amat kritikal memandangkan perbezaan kecil dalam reka bentuknya akan secara langsung mempengaruhi kecekapan pembakaran. Fungsi utama injektor adalah untuk memecahkan bahan api kepada titisan yang amat kecil. Titisan kecil penting untuk pembakaran pantas secara senyap dan untuk mewujudkan satu nyalaan di hadapan, berhampiran dengan kepala injektor, maka kebuk pembakaran yang lebih pendek berkemungkinan dapat digunakan. Kertas kerja ini mebentangkan satu penyelidikan eksperimental sebuah injektor ekabahan dorong geronggang kon pusar. Beberapa injektor dengan konfigurasi berbeza telah dikaji di bawah ujian aliran sejuk, di mana air digunakan sebagai bendalir simulasi. Kajian ini mendedahkan bahawa suntikan bertekanan tinggi menghasilkan sudut semburan kon yang besar. Kesan tekanan suntikan ke atas sudut semburan kon lebih ketara pada injektor yang mempunyai lubang tangen yang kurang Tambahan pula, injektor yang mempunyai jumlah lubang tangen yang paling banyak dan lubang tangen berdiameter paling kecil menghasilkan semburan yang paling lebar. Data eksperimental juga menunjukkan bahawa diameter teras udara terbesar terhasil di dalam kebuk pusar injektor yang mempunyai diameter lubang tangen terkecil dan jumlah lubang tangen yang paling kurang.

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High-Pressure Electronic Fuel Injection for Small-Displacement Single-Cylinder Diesel Engine

Volume 2: Emissions Control Systems; Instrumentation, Controls, and Hybrids; Numerical Simulation; Engine Design and Mechanical Development ◽

10.1115/icef2015-1029 ◽

2015 ◽

Author(s):

Andrew L. Carpenter ◽

Robert E. Mayo ◽

Jerald G. Wagner ◽

Paul E. Yelvington

Keyword(s):

High Pressure ◽

Diesel Engines ◽

Fuel Injection ◽

Injection Pressure ◽

Injection System ◽

Orifice Diameter ◽

Small Displacement ◽

Fuel System ◽

Single Cylinder ◽

Injection Parameters

Small-displacement, single-cylinder, diesel engines employ mechanically actuated fuel injection systems. These mechanically governed systems, while robust and low-cost, lack the ability to fully vary injection parameters, such as timing, pulse duration, and injection pressure. The ability of a particular injection system to vary these injection parameters impacts engine efficiency, power, noise, and emissions. Modern, multi-cylinder automotive engines employ some form of electronically controlled injection to take advantage of the benefits of fully variable injection, including advanced strategies such as multi-pulse injections and rate shaping. Modern diesel electronic fuel injection systems also operate at considerably higher injection pressures than mechanical fuel systems used in small-bore industrial engines. As the cost of electronic fuel systems continues to decrease and the demand for high-efficiency engines increases, electronic fuel injection becomes a more viable option for incorporation into small industrial diesel engines. In particular, this technology may be well-suited for demanding and critical applications such as military power generation. In this study, a small-bore, single-cylinder diesel was retrofit with a custom, four-hole, high-pressure electronic fuel system. Compared to the mechanical injector, the electronic, common-rail injector had a 50% smaller orifice diameter and was designed for a 4x higher injection pressure. The mechanical governor was also replaced with an electronic speed controller. The baseline and modified engines were installed on a dynamometer, and measurements of exhaust emissions, fuel consumption, brake torque, and in-cylinder pressure were made. The electronic injector led to lower smoke opacity and NOx emissions, while CO and hydrocarbon emissions were observed to increase slightly, likely due to some wall wetting of fuel with the initial prototype injector. Testing with low ignition quality fuels was also performed, and the electronic fuel system enabled the engine to operate with fuel having a cetane number as low as 30.

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High-Pressure Electronic Fuel Injection for Small-Displacement Single-Cylinder Diesel Engines

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4032920 ◽

2016 ◽

Vol 138 (10) ◽

Cited By ~ 2

Author(s):

Andrew L. Carpenter ◽

Robert E. Mayo ◽

Jerald G. Wagner ◽

Paul E. Yelvington

Keyword(s):

High Pressure ◽

Diesel Engines ◽

Fuel Injection ◽

Cetane Number ◽

Injection Pressure ◽

Injection System ◽

Orifice Diameter ◽

Small Displacement ◽

Single Cylinder ◽

Injection Parameters

Small-displacement single-cylinder diesel engines employ mechanically actuated fuel injection systems. These mechanically governed systems, while robust and low cost, lack the ability to fully vary injection parameters, such as timing, pulse duration, and injection pressure. The ability of a particular injection system to vary these injection parameters impacts engine efficiency, power, noise, and emissions. Modern, multicylinder automotive engines employ some form of electronically controlled injection to take advantage of the benefits of fully variable injection, including advanced strategies such as multipulse injections and rate shaping. Modern diesel electronic fuel injection (EFI) systems also operate at considerably higher injection pressures than mechanical fuel systems used in small-bore industrial engines. As the cost of electronic fuel systems continues to decrease and the demand for high-efficiency engines increases, EFI becomes a more viable option for incorporation into small industrial diesel engines. In particular, this technology may be well-suited for demanding and critical applications, such as military power generation. In this study, a small-bore single-cylinder diesel was retrofit with a custom high-pressure EFI system. Compared to the mechanical injector, the electronic, common-rail injector had a 50% smaller orifice diameter and was designed for a fourfold higher injection pressure. The mechanical governor was also replaced with an electronic speed controller. The baseline and modified engines were installed on a dynamometer, and measurements of exhaust emissions, fuel consumption, brake torque, and in-cylinder pressure were made. The electronic injector leads to lower smoke opacity and NOx emissions, while CO and hydrocarbon emissions were observed to increase slightly, likely due to some wall wetting of fuel with the initial prototype injector. Testing with low ignition quality fuels was also performed, and the electronic fuel system enabled the engine to operate with fuel having a cetane number as low as 30.

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Causes of gear pump fails and methods for their elimination

Tekhnicheskiy servis mashin ◽

10.22314/2618-8287-2020-58-3-98-107 ◽

2020 ◽

pp. 98-107

Author(s):

Vitaliy A. Zuyevskiy ◽

Daniil O. Klimyuk ◽

Ivan A. Shemberev

Keyword(s):

Adhesion Strength ◽

Production Systems ◽

Low Cost ◽

High Strength ◽

Strength Properties ◽

Research Purpose ◽

Working Fluid ◽

Gear Pump ◽

Repair Service ◽

Recovery Method

Gear pumps are an important element of many production systems and their replacement in case of failure can be quite expensive, so it is important to have a modern and well-tuned technology for their recovery. There are many methods for restoring the pump's performance, depending on the reason that led to its failure. (Research purpose) The research purpose is in determining what causes most often lead to loss of pump performance, and developing a recovery method that provides the greatest post-repair service life of the pump and low cost of repair. (Materials and methods) Authors took into account that the applied coatings must have sufficient adhesion strength and resistance to mechanical, thermal and corrosion loads during operation. It was found that most often significant leaks of the working fluid, leading to failure, occur due to an increase in the gap between the inner surface of the housing and the gears due to active wear of the housing wells. Authors determined that the method of electric spark treatment of worn-out housing wells is best suited to perform the task (a large post-repair resource and low costs). (Results and discussion) It was found by laboratory studies of the adhesion strength of electric spark coatings with various electrodes that the best transfer of the material to the substrate is provided by bronze electrodes BrMKts3-1. It was noted that the coatings applied using the BrMKts3-1 electrode have high strength properties. (Conclusions) Research conducted in the center for collective use "Nano-Center" VIM confirmed the possibility of effective recovery of the gear pump by electric spark treatment.

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Numerical investigation of injection parameters and piston bowl geometries on emission and thermal performance of DI diesel engine

SN Applied Sciences ◽

10.1007/s42452-021-04633-1 ◽

2021 ◽

Vol 3 (6) ◽

Author(s):

Ikhtedar Husain Rizvi ◽

Rajesh Gupta

Keyword(s):

Diesel Engine ◽

Thermal Performance ◽

Equivalence Ratio ◽

Fuel Injection ◽

Injection Pressure ◽

Injection Nozzle ◽

Piston Bowl ◽

Injection Parameters ◽

Nozzle Size ◽

Engine Emission

AbstractTightening noose on engine emission norms compelled manufacturers globally to design engines with low emission specially NOx and soot without compromising their performance. Amongst various parameters, shape of piston bowls, injection pressure and nozzle diameter are known to have significant influence over the thermal performance and emission emanating from the engine. This paper investigates the combined effect of fuel injection parameters such as pressure at which fuel is injected and the injection nozzle size along with shape of piston bowl on engine emission and performance. Numerical simulation is carried out using one cylinder naturally aspirated diesel engine using AVL FIRE commercial code. Three geometries of piston bowls with different tumble and swirl characteristics are considered while maintaining the volume of piston bowl, compression ratio, engine speed and fuel injected mass constant along with equal number of variations for injection nozzle size and pressures for this analysis. The investigation corroborates that high swirl and large turbulence kinetic energy (TKE) are crucial for better combustion. TKE and equivalence ratio also increased as the injection pressure increases during the injection period, hence, enhances combustion and reduces soot formation. Increase in nozzle diameter produces higher TKE and equivalence ratio, while CO and soot emission are found to be decreasing and NOx formation to be increasing. Further, optimization is carried out for twenty-seven cases created by combining fuel injection parameters and piston bowl geometries. The case D2H1P1 (H1 = 0.2 mm, P1 = 200 bar) found to be an optimum case because of its lowest emission level with slightly better performance.

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Optimization of Fuel Injection Parameters of Moringa oleifera Biodiesel-Diesel Blend for Engine-Out-Responses Improvements

Symmetry ◽

10.3390/sym13060982 ◽

2021 ◽

Vol 13 (6) ◽

pp. 982

Author(s):

Yew Heng Teoh ◽

Heoy Geok How ◽

Farooq Sher ◽

Thanh Danh Le ◽

Hwai Chyuan Ong ◽

...

Keyword(s):

Diesel Engines ◽

Fossil Fuels ◽

Moringa Oleifera ◽

Fuel Injection ◽

Injection Pressure ◽

Single Step ◽

Rapid Decline ◽

Fuel Blend ◽

Combustion Dynamics ◽

Rsm Optimization

Biodiesel has gained popularity in diesel engines as a result of the rapid decline of fossil fuels and population growth. The processing of biodiesel from non-edible Moringa Oleifera was investigated using a single-step transesterification technique. Both fuels had their key physicochemical properties measured and investigated. In a common-rail diesel engine, the effects of MB50 fuel blend on the symmetric characteristics of engine-out responses were evaluated under five load settings and at 1000 rpm. As compared to standard diesel, MB50 increased brake thermal efficiency (BTE), and nitrogen oxides (NOx) emissions while lowering brake specific fuel consumption (BSFC), and smoke emissions for all engine loads. A further study of injection pressure and start of injection (SOI) timing for MB50 fuel was optimized using response surface methodology (RSM). The RSM optimization resulted in improved combustion dynamics due to symmetry operating parameters, resulting in a simultaneous decrease in NOx and smoke emissions without sacrificing BTE. RSM is an efficient optimization method for achieving optimal fuel injection parameter settings, as can be deduced. As a result, a clearer understanding of the use of MB50 fuel in diesel engines can be given, allowing for the best possible engine efficiency.

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