scholarly journals Optimization of Design and Technology of Injector Nozzles in Terms of Minimizing Energy Losses on Friction in Compression Ignition Engines

2021 ◽  
Vol 11 (16) ◽  
pp. 7341
Author(s):  
Jan Monieta ◽  
Lech Kasyk
Keyword(s):  
Surface Condition ◽  
Engine Performance ◽  
Optimization Methods ◽  
Operating Conditions ◽  
Technical State ◽  
Design And Technology ◽  
Design Parameters ◽  
Pressure Losses ◽  
Injection Apparatus

The operation of injection apparatus in self-ignition engines results from the design, manufacturing technology and wear and tear during operation. The technical state of the injector apparatus significantly affects the engine performance, fuel consumption, toxicity and smoke opacity of outlet gases. The most unreliable element of the injection apparatus is the injector nozzle, the quality of which depends on the quality of construction and production, operating conditions and the of the fuels used, etc. One of the design parameters of the injector nozzles, determining the technical state is the geometry of the nozzle holes. An attempt was made to optimize the selection of the dimensions and surface condition of the spray holes to significantly affect the flow properties of the injector nozzles and, consequently, to decide on the size and form of fuel dosed streams to individual cylinders of a self-ignition engine and the quality of fuel atomization. In work, a simulation model was developed, and the pressure losses and the mass fluid of the injected fuel were minimized for selected significant geometric features, taking into account the influence of operating conditions. With the use of Mathematica software, simulation optimization methods and methods based on evolutionary algorithms were elaborated.

Gas Turbine Performance: New Application and Test Correction Curves

1995 ◽  
Author(s):  
Scott T. Cloyd ◽  
Arthur J. Harris
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Engine Performance ◽  
Exhaust System ◽  
Operating Parameter ◽  
Operating Conditions ◽  
Engine Operation ◽  
Pressure Losses ◽  
System Pressure ◽  
Oil Fuel

The gas turbine industry has adopted the practice of rating engine performance at ISO standard conditions; 15 degrees C, 1.033 ata, 100% methane fuel, and no inlet or exhaust system pressure losses with power output referenced to the generator terminals. (ISO, 1989) While these standards are useful in putting original equipment manufacturers’ (OEM’s) ratings on an equivalent basis it is not likely that an engine would be installed or tested under these types of conditions. To account for variations in engine operating conditions equipment manufacturers’ have utilized performance correction curves to show the influence of changing one operating parameter while holding all others constant. The purpose of this paper is to review the correction curves that are used for initial project application studies, and the variations to the curves that occur when a unit is put into service as a result of the methods used to control engine operation. Sample corrections curves and a brief explanation of the correction curves are presented to illustrate the variations in the curves. The paper also presents a new method for illustrating the influence of fuel heating value and composition on engine performance for natural gas and oil fuel. All data presented is for a single shaft, constant speed gas turbine. Two shaft or three shaft gas turbines will not have these correction curves.

scholarly journals Optimization of Parameters and Operating Modes of Disc Sowing Device According to Seeding Uniformity Criterion

2018 ◽  
Vol 28 (3) ◽  
pp. 379-388
Author(s):  
Vladimir A. Ovchinnikov ◽  
Mikhail N. Chatkin ◽  
Alena V. Ovchinnikova
Keyword(s):  
Experimental Studies ◽  
Operating Conditions ◽  
Design Parameters ◽  
Optimal Parameters ◽  
Plant Growth And Development ◽  
Important Condition ◽  
Operating Modes ◽  
Favorable Conditions ◽  
Uniformity Criterion

Introduction. When cultivating agricultural crops, it is necessary to take into account the plants’ need for moisture, nutrients, location by area of nutrition, determining illumination, etc. Taking into account the biological characteristics of crops, various methods of sowing are used to create favorable conditions for plant growth and development. An important condition for sowing is the uniform arrangement of seeds along the sulcus, especially in the cultivation of testes of small-seeded cultures. A key role in the uniformity of seeding is provided by the design parameters and kinematic operating conditions of the sowing device. Materials and Methods. To determine the optimal parameters and operating modes of the disk sowing device, methods of factor experiment and multi-criteria optimization were used. Results. Mathematical models of the technological process of sowing seeds were obtained based of experimental studies. Conclusions. To ensure the improvement of the seeding quality of small seeds, the design parameters of the experimental seeder: х4 – is the diameter of the cell; х5 – the number of cells on the disk, will tend to the maximum values. The optimum circumferential speed of the sowing disk should be in the range from 0.127 to 0.192 m/s, and the speed of the machine’s movement is no more than 2 m/s.

CFD Simulation of an Alfa-Stirling Engine to Study the Geometrical Parameters on the Engine Performance

2019 ◽  
Author(s):  
Ana C. Ferreira ◽  
Senhorinha F. C. F. Teixeira ◽  
Ricardo F. Oliveira ◽  
José C. Teixeira
Keyword(s):  
Heat Exchanger ◽  
Power Output ◽  
Cfd Simulation ◽  
Engine Performance ◽  
Stirling Engine ◽  
Operating Conditions ◽  
Design Parameters ◽  
Working Fluid ◽  
Cold Temperatures ◽  
Temperature Heat

Abstract An alpha-Stirling configuration was modelled using a Computational Fluid Dynamic (CFD), using ANSYS® software. A Stirling engine is an externally heated engine which has the advantage of working with several heat sources with high efficiencies. The working gas flows between compression and expansion spaces by alternate crossing of, a low-temperature heat exchanger (cooler), a regenerator and a high-temperature heat exchanger (heater). Two pistons positioned at a phase angle of 90 degrees were designed and the heater and cooler were placed on the top of the pistons. The motion of the boundary conditions with displacement was defined through a User Defined Function (UDF) routine, providing the motion for the expansion and compression piston, respectively. In order to define the temperature differential between the engine hot and the cold sources, the walls of the heater and cooler were defined as constant temperatures, whereas the remaining are adiabatic. The objective is to study the thermal behavior of the working fluid considering the piston motion between the hot and cold sources and investigate the effect of operating conditions on engine performance. The influence of regenerator matrix porosity, hot and cold temperatures on the engine performance was investigated through predicting the PV diagram of the engine. The CFD simulation of the thermal engine’s performance provided a Stirling engine with 760W of power output. It was verified that the Stirling engine can be optimized when the best design parameters combination are applied, mostly the regenerator porosity and cylinders volume, which variation directly affect the power output.

scholarly journals Problems of Friction Force Measurement between Cylindrical Outdoor and Internal Slide Parts

2018 ◽  
Vol 1 (1) ◽  
pp. 19-25
Author(s):  
Jan Monieta
Keyword(s):  
Friction Force ◽  
Surface State ◽  
Force Measurement ◽  
Surface Condition ◽  
Frictional Resistance ◽  
Experimental Tests ◽  
Technical State ◽  
Force Model ◽  
Factors Affecting

Abstract The article presents the determination of an exemplary measure in the assessment of the technical state of sets of mechanical objects at the stage of manufacture, use and maintenance. The technical state of the assemblies is influenced by the quality of the friction-cooperating elements, the quality of basic functions, the surroundings and the diameter clearance of kinematic node components. Energy wasted to overcome the frictional resistance is a significant part of the energy supplied, which is why current friction losses are minimized. The article includes analysis of the phenomena occurring in the cylindrical pairs in the presence of static and kinetic friction. The many factors affecting the course and values of friction force between cylindrical elements performing relative reciprocating motion have been indicated. The subject of the article is the method of measuring the friction force between a fixed and movable cylindrical element of the mechanical object. The gradual increase of the friction force component takes place by means of easily accessible force. The results of experimental tests of the friction force in different laboratory conditions under are also included. The effect on the measured friction force was investigated: of friction elements geometry and the surface condition after manufacture and/or operation. Scatter results of static friction force depending on the geometry and surface state can be significant. Examples of surface state images are shown. A friction force model was also developed depending on factors affecting its value.

The Operational Mixture Limits in Engines Fueled With Alternative Gaseous Fuels

2006 ◽  
Vol 128 (3) ◽  
pp. 223-228 ◽  
Author(s):  
S. O. Bade Shrestha ◽  
Ghazi A. Karim
Keyword(s):  
Engine Performance ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Design Parameters ◽  
Compression Ignition ◽  
Gaseous Fuels ◽  
Compression Ignition Engines ◽  
Wide Range ◽  
Operational Life ◽  
Experimental Values

The operation of engines whether spark ignition or compression ignition on a wide range of alternative gaseous fuels when using lean mixtures can offer in principle distinct advantages. These include better economy, reduced emissions, and improved engine operational life. However, there are distinct operational mixture limits below which acceptable steady engine performance cannot be sustained. These mixture limits are usually described as the “lean operational limits,” or loosely as the ignition limits which are a function of various operational and design parameters for the engine and fuel used. Relatively simple approximate procedures are described for predicting the operational mixture limits for both spark ignition and dual fuel compression ignition engines when using a range of common gaseous fuels such as natural gas/methane, propane, hydrogen, and some of their mixtures. It is shown that good agreement between predicted and corresponding experimental values can be obtained for a range of operating conditions for both types of engines.

CFD Thermal Analysis and Optimization of Motor Cooling Fin Design

2005 ◽  
Author(s):  
Ya-Chi Chen ◽  
Bing-Chung Chen ◽  
Chung-Lung Chen ◽  
Jimmy Q. Dong
Keyword(s):  
Parametric Design ◽  
Numerical Data ◽  
Optimization Procedure ◽  
Optimization Methods ◽  
Sensitivity Study ◽  
Operating Conditions ◽  
Design Parameters ◽  
Efficient Design ◽  
Motor Cooling ◽  
Fin Design

This study is focused on improving cooling performance of the housing fin for Total Enclosed Fan Cooled (TEFC) motors. We conducted a sensitivity study on the motor housing fin to determine key design parameters and developed an optimization procedure. The goal is to use the optimizer to achieve an efficient design process for optimal fin design under specified operating conditions. Response Surface Methodology (RSM) was constructed out of the numerical data with multi-quadratics (MQ) as basis functions to predict the response. The RSM, in conjunction with generic optimization methods, was used to find the optimal fin design in the parametric design space. The parameter database was non-dimensionalized so that the optimizer can be applied to various motor frame sizes. Compared with the original fin design, in some cases the optimal fin configuration reduces thermal resistance to heat convection from the fin surface by more than 50%.

Fluid-Dynamic Analysis and Optimization of the Quenching Process for Hardening of Change-Speed Gears Using DOE–ANOVA Method

2004 ◽  
Vol 126 (3) ◽  
pp. 365-375 ◽  
Author(s):  
Paolo M. Congedo ◽  
Antonio Ficarella ◽  
Domenico Laforgia
Keyword(s):  
Fluid Dynamic ◽  
Operating Conditions ◽  
Design Parameters ◽  
Cooling Process ◽  
Dynamic Calculation ◽  
Hardening Process ◽  
Performance Indexes ◽  
Quenching Process ◽  
Geometry Configuration

This investigation deals with the fluid-dynamic behavior of the hardening process for change-speed gears, where a Nitrogen high pressure flow is used for quenching. At the end of the process, the gears showed a high planarity error due to a slow and non-homogeneous cooling process. A detailed fluid-dynamic calculation was performed to identify some possible technical improvements, such as varying some design parameters including the geometry configuration of the quenching chamber and the operating conditions. Three performance indexes have been defined to synthesize the quality of the hardening process and their trends have been evaluated as a function of the design and operative configuration by a DOE–ANOVA statistical analysis to obtain the best configuration.

scholarly journals POROUS CONSTRUCTIONS OF WATER INTAKE STRUCTURES

2020 ◽  
pp. 149-155
Author(s):  
V. Progulny ◽  
◽  
N. Hurinchyk ◽  
I. Grachov ◽  
K. Borysenko ◽  
...  
Keyword(s):  
Water Supply ◽  
Water Intake ◽  
Juvenile Fish ◽  
Essential Element ◽  
Operating Conditions ◽  
Hydraulic Calculation ◽  
Normal Operation ◽  
Design Parameters ◽  
Polymer Concrete

Abstract. Water intake is an essential element of the water supply complex, normal operation of which depends on the quality of the water delivered to the consumer. Therefore, the water supply system should be effectively protected from various contaminants from the source, ice slurries, and juvenile fish. The authors analyze the operation of existing coarse screen devices in channel water intakes; identify their main disadvantages, such as: mechanical jamming (clogging) of the screen holes with debris, leading to its failure and the need to replace, as well as the laborious cleaning and the high cost of screen materials. The article notes that during operation there is an increase in the pressure drop affecting the screen due to the accumulation of a large amount of contaminants on its surface, which could lead to a throughput and a significant amount of pollution. To improve the quality of filtered water and operating conditions, the authors proposed to provide porous pipes installation instead of flat removable screens in the receiving section of the intake well. The material for their manufacture is a polymer concrete, based on crushed granite stones or gravel and a polymer binder – epoxy resin. The article shows the scheme of intake well pipes installation, describes the principle of the proposed design, shows a graph obtained as a result of hydraulic calculation. This design has a number of advantages over flat screens: automation of flushing, less clogging, greater throughput, lack of biofouling, high strength characteristics, low hydraulic resistance and durability. A porous polymer concrete-based structure, which is a pipe system that increases the reliability of water intakes, improves the quality of the water taken from the source and the conditions of operation, has been proposed. The method of hydraulic calculation of porous pipes makes it possible to optimize their design parameters, to determine the diameter and pressure loss in them, which is very important when designing water intakes. The aim of further research is to study the dynamics and degree of porous devices clogging by suspension at different concentrations in natural water.

The Operational Mixture Limits in Engines Fueled With Alternative Gaseous Fuels

2005 ◽  
Author(s):  
S. O. Bade Shrestha ◽  
Ghazi A. Karim
Keyword(s):  
Engine Performance ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Design Parameters ◽  
Compression Ignition ◽  
Gaseous Fuels ◽  
Compression Ignition Engines ◽  
Wide Range ◽  
Operational Life ◽  
Experimental Values

The operation of engines whether spark ignition or compression ignition on a wide range of alternative gaseous fuels when using lean mixtures, can offer in principle distinct advantages. These include better economy, reduced emissions and improved engine operational life. However, there are distinct operational mixture limits below which acceptable steady engine performance cannot be sustained. These mixture limits are usually described as the “lean operational limits”, or loosely as the ignition limits which are a function of various operational and design parameters for the engine and fuel used. Through experimental investigation and analytical simulation of engine performance, relatively simple approximate procedures are described for predicting the operational mixture limits for both spark ignition and dual fuel compression ignition engines when using a range of common gaseous fuels such as natural gas/methane, propane, hydrogen and some of their mixtures. It is to be shown that good agreement between the predicted and corresponding experimental values can be obtained for a range of operating conditions for both types of engines.

Analyzing the Effect of Engine Design Modification on the Spark-Ignition Engine Performance via Simplified Quasi-Dimensional Modeling

2017 ◽  
Author(s):  
Yirop Kim ◽  
Myoungsoo Kim ◽  
Han Ho Song
Keyword(s):  
Burning Rate ◽  
Engine Performance ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Optimization Process ◽  
Design Parameters ◽  
Ic Engine ◽  
Design Modification ◽  
Engine Design ◽  
Flow Motion

For past decades, substantial developments have been accomplished in internal combustion (IC) engine technology, but there still remain some possible improvements. The combustion in an IC engine is a highly intricate phenomenon, thus, numerous factors correlated with different forms of loss decides the efficiency of an engine. In spark-ignition (SI) engines, the combustion duration is considered important because it plays a key role in determining the combustion phasing for best possible energy conversion. The geometry of engine components may directly change the burning rate of air-fuel mixture, therefore, it should also be considered as significant as other aspects like exhaust gas recirculation (EGR) rate or boosting in investigation of the engine performance. This is the reason the development engineers are putting their effort to design an engine with optimized flow motion. Tweaking the flow dynamics via design modification or use of auxiliary device influences the turbulence level inside the combustion chamber, thus, the burning rate as well. Intake port orientation, masking, and piston shape are one of the typical design parameters manipulated for such purpose, and profound understanding on the effect of these design parameters on burning rate is encouraged in order to assist the optimization process. The design optimization process should be based on a fundamental understanding of how the design parameters affect the flow motion and combustion characteristics. This study aims for a simpler and faster method to investigate the consequences of design modifications. As a base model, a physics-based quasi-dimensional (QD) engine model is developed for simulation of SI combustion phenomenon. It is modeled to consider the change in flow motion and turbulence properties via simplified modeling. The advantages of such QD model is that it requires much less computational resource compared to 3D CFD model, and allows a greater degree of freedom within the simulation process which facilitates parametric studies. A zero-dimensional (0D) turbulence submodel is used to describe energy cascade mechanism, and turbulence intensity is calculated reflecting the effect cause by design modification. According to the sensitivities drawn from parametric study, the results of each effect on burning rate and other engine performance properties are compared individually and collectively. A qualitative analysis suggests how sensitive each effect are at given operating conditions. The result infers that the flow concentration by port design modification boosts the burning rate, but it is advantageous in terms of fuel economy to enhance the breathing ability by valve masking. The product of this comparative study assists an intuitive understanding on how the design modification would affect the engine operations, and it is encouraged to develop the model further via validation with experiment data to provide more reliable output. It is believed that it can be utilized as a good reference in engine design process.

Sign in / Sign up

Export Citation Format

Share Document