Paper 2: Similarity Considerations in Assessing Diesel Engine Fuel Spray Requirements

1965 ◽  
Vol 180 (14) ◽  
pp. 10-29 ◽  
Author(s):  
B. E. Knight
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Engine Performance ◽  
Fuel Spray ◽  
Theoretical Expression ◽  
Engine Fuel ◽  
Wide Range ◽  
Air Mixing ◽  
Dimensionless Variables ◽  
Mixing Problem

A simplified dimensional analysis has been made of the fuel-air mixing problem in diesel engines. The dimensionless variables describing the mixing pattern have been expressed in terms of the dimensionless variables describing the engine and fuel injection conditions by means of explicit equations with numerical values for the constants. A wide range of such equations has been derived and tables of numerical values are given as examples, together with examples of engine air motion calculations for comparison. A theoretical expression for fuel-spray penetration into a cross-wind has been compared with a few experimental results. Engine smoke and specific consumption measurements have been plotted against the appropriate dimensionless variables in two instances. In both instances the response of the engine to the variables is quite different. It is believed that the wide range of methods of engine performance data analysis outlined in this paper will make a significant contribution to progress in understanding diesel engine combustion.

Numerical Simulation of the Effects of the Nozzle Parameters on In-Cylinder Fuel and Air Mixing Process

2013 ◽  
Vol 401-403 ◽  
pp. 218-221
Author(s):  
Qi Liu ◽  
Guang Yao Ouyang ◽  
Shi Jie An ◽  
Yu Peng Sun
Keyword(s):  
Numerical Simulation ◽  
Diesel Engine ◽  
Fuel Injection ◽  
Combustion Model ◽  
Engine Fuel ◽  
Three Dimension ◽  
Mixing Process ◽  
Fuel Injector ◽  
Injection Process ◽  
Air Mixing

In order to study the injection property of diesel engine fuel injector, the three-dimension combustion model of TBD620 diesel engine is constructed on the AVL Fire software platform. A numerical simulation of the two injectors’ fuel injection process at different load conditions has been done. The influence on fuel and air mixing process is analyzed. The results show that the special injector has a good performance at low load, but the standard injector is more favorable for fuel and air fully mixing at high load.

Diesel engine performance mapping using a parametrized mixing time model

2017 ◽  
Vol 19 (2) ◽  
pp. 202-213 ◽  
Author(s):  
Michal Pasternak ◽  
Fabian Mauss ◽  
Christian Klauer ◽  
Andrea Matrisciano
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Mixing Time ◽  
Combustion Process ◽  
Engine Performance ◽  
Injection Timing ◽  
Engine Control ◽  
Reactor Model ◽  
Time Model ◽  
Tabulated Chemistry

A numerical platform is presented for diesel engine performance mapping. The platform employs a zero-dimensional stochastic reactor model for the simulation of engine in-cylinder processes. n-Heptane is used as diesel surrogate for the modeling of fuel oxidation and emission formation. The overall simulation process is carried out in an automated manner using a genetic algorithm. The probability density function formulation of the stochastic reactor model enables an insight into the locality of turbulence–chemistry interactions that characterize the combustion process in diesel engines. The interactions are accounted for by the modeling of representative mixing time. The mixing time is parametrized with known engine operating parameters such as load, speed and fuel injection strategy. The detailed chemistry consideration and mixing time parametrization enable the extrapolation of engine performance parameters beyond the operating points used for model training. The results show that the model responds correctly to the changes of engine control parameters such as fuel injection timing and exhaust gas recirculation rate. It is demonstrated that the method developed can be applied to the prediction of engine load–speed maps for exhaust NOx, indicated mean effective pressure and fuel consumption. The maps can be derived from the limited experimental data available for model calibration. Significant speedup of the simulations process can be achieved using tabulated chemistry. Overall, the method presented can be considered as a bridge between the experimental works and the development of mean value engine models for engine control applications.

scholarly journals Performance Assessment of DI-Diesel Engine using the Blend of Sunflower Oil and Rice Bran Oil

2019 ◽  
Vol 8 (4) ◽  
pp. 4048-4052
Keyword(s):  
Diesel Engine ◽  
Sunflower Oil ◽  
Fuel Injection ◽  
Rice Bran Oil ◽  
Engine Performance ◽  
Performance And Emission ◽  
Animal Fats ◽  
Di Diesel Engine ◽  
Hc Emissions ◽  
Direct Fuel Injection

Biodiesel, a derivative of vegetable oils and animal fats, is used nowadays as an alternative renewable and sustainable fossil fuel. In this work, the investigation of manufacture, characterization, and results of biodiesel blends are carried out using two important feedstock’s, sunflower oil and ricebran oil on engines. For the collective advantageous of sunflower oil and ricebran oil, the two biodiesels are combined together and the mixture is analysed to assess the engine performance and emission characteristics. NaOH catalyzed transesterification process is used for producing the Biodiesels A 4.4 kW, four-stroke, single-cylinder and direct fuel injection diesel engine is used for measuring physic-chemical with full load and varying speed conditions and using the specifications of ASTM D6751 standard, the properties are compared. It is observed that the Biodiesel mixtures produce a low brake torque and high brake-specific fuel consumption (BSFC) in addition to the reduction of CO and HC emissions. NOx, however, is reduced considerably with the improvement of brake thermal efficiency. The Performance analysis indicates that the mixture of sunflower oil and ricebran oil improves performance and emission characterizes over sunflower oil and ricebran oil biodiesel when they are unmixed..

Analysis of Throttle Opening Variation Impact on a Diesel Engine Performance Using Second Law of Thermodynamics

2009 ◽  
Author(s):  
B. B. Sahoo ◽  
U. K. Saha ◽  
N. Sahoo ◽  
P. Prusty
Keyword(s):  
Diesel Engine ◽  
Direct Injection ◽  
Fuel Efficiency ◽  
Engine Performance ◽  
Second Law Of Thermodynamics ◽  
Operating Conditions ◽  
Second Law ◽  
Engine Fuel ◽  
Availability Analysis ◽  
Second Law Analysis

The fuel efficiency of a modern diesel engine has decreased due to the recent revisions to emission standards. For an engine fuel economy, the engine speed is to be optimum for an exact throttle opening (TO) position. This work presents an analysis of throttle opening variation impact on a multi-cylinder, direct injection diesel engine with the aid of Second Law of thermodynamics. For this purpose, the engine is run for different throttle openings with several load and speed variations. At a steady engine loading condition, variation in the throttle openings has resulted in different engine speeds. The Second Law analysis, also called ‘Exergy’ analysis, is performed for these different engine speeds at their throttle positions. The Second Law analysis includes brake work, coolant heat transfer, exhaust losses, exergy efficiency, and airfuel ratio. The availability analysis is performed for 70%, 80%, and 90% loads of engine maximum power condition with 50%, 75%, and 100% TO variations. The data are recorded using a computerized engine test unit. Results indicate that the optimum engine operating conditions for 70%, 80% and 90% engine loads are 2000 rpm at 50% TO, 2300 rpm at 75% TO and 3250 rpm at 100% TO respectively.

scholarly journals Comparison of the Emissions, Noise, and Fuel Consumption Comparison of Direct and Indirect Piezoelectric and Solenoid Injectors in a Low-Compression-Ratio Diesel Engine

Energies ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 4023 ◽  
Author(s):  
Stefano d’Ambrosio ◽  
Alessandro Ferrari ◽  
Alessandro Mancarella ◽  
Salvatore Mancò ◽  
Antonio Mittica
Keyword(s):  
Diesel Engine ◽  
Fuel Consumption ◽  
Compression Ratio ◽  
Fuel Injection ◽  
Engine Performance ◽  
Combustion Noise ◽  
Driving System ◽  
Performance And Emissions ◽  
Direct Acting ◽  
Engine Performance And Emissions

An experimental investigation has been carried out to compare the performance and emissions of a low-compression-ratio Euro 5 diesel engine featuring high EGR rates, equipped with different injector technologies, i.e., solenoid, indirect-acting, and direct-acting piezoelectric. The comparisons, performed with reference to a state-of-the-art double fuel injection calibration, i.e., pilot-Main (pM), are presented in terms of engine-out exhaust emissions, combustion noise (CN), and fuel consumption, at low–medium engine speeds and loads. The differences in engine performance and emissions of the solenoidal, indirect-acting, and direct-acting piezoelectric injector setups have been found on the basis of experimental results to mainly depend on the specific features of their hydraulic circuits rather than on the considered injector driving system.

Study on Altitude Adaptability of a Turbocharged Off-Road Diesel Engine

2020 ◽  
Vol 142 (11) ◽  
Author(s):  
Fenlian Huang ◽  
Jilin Lei ◽  
Qianfan Xin
Keyword(s):  
Diesel Engine ◽  
Engine Performance ◽  
Spray Angle ◽  
Fuel Spray ◽  
Intake Manifold ◽  
Bench Test ◽  
Boost Pressure ◽  
Exhaust Manifold ◽  
Power Performance ◽  
Operating Characteristics

Abstract This paper investigates the operating characteristics of an off-road diesel engine to enhance its power performance in plateau. First, the impacts of altitude on the power, fuel economy, and emissions characteristics were analyzed by a bench test. Second, the combustion and overall performance working at different altitudes were studied by three-dimensional numerical simulation, including the relationship between fuel injection parameters and engine performance. The results showed that altitude significantly affects the performance of the off-road diesel engine. As the altitude increased from 0 m to 2000 m, the engine power decreased as much as 4.3%, and the brake-specific fuel consumption (BSFC) increased as much as 6%. At the peak torque condition, the intake manifold boost pressure and the exhaust manifold pressure both reduced with a rise of altitude, while the intake and exhaust manifold temperatures both increased with a rise of altitude. Finally, after comparing the in-cylinder flow conditions and combustion characteristics given by six combustion chamber designs that have different shrinkage ratios, the engine performance at 4000 m altitude with five different fuel spray angles were further optimized. The engine rated power increased by 8.2% when the shrinkage ratio was 7.28% and the fuel spray angle was 150 deg at the 4000 m altitude.

Diesel Engine Fuel Injection Control Using a Model-Guided Extremum-Seeking Method

2015 ◽  
Author(s):  
Prasad Divekar ◽  
Qingyuan Tan ◽  
Xiang Chen ◽  
Ming Zheng ◽  
Ying Tan
Keyword(s):  
Diesel Engine ◽  
Fuel Injection ◽  
Online Optimization ◽  
Extremum Seeking ◽  
External Boundary ◽  
Experimental Investigations ◽  
Control Input ◽  
Engine Fuel ◽  
Engine Model ◽  
Injection Control

Diesel engine fuel injection control is presented as a feedback based online optimization problem. Extremum seeking (ES) approach is used to address the online optimization formulation. The cost function is synthesized from extensive experimental investigations such that the indicated thermal efficiency of the engine is maximized while minimizing the NOx emissions under external boundary conditions. Knowledge of the physical combustion and emission formation process based on a pre-calibrated non-linear engine model output is used to determine the ES initial control input to minimize the seeking time. The control is demonstrated on a hardware-in-the-loop engine simulator bench.

Scaling liquid penetration in evaporating sprays for different size diesel engines

2019 ◽  
Vol 21 (9) ◽  
pp. 1662-1677 ◽  
Author(s):  
Xinyi Zhou ◽  
Tie Li ◽  
Yijie Wei ◽  
Ning Wang
Keyword(s):  
Diesel Engine ◽  
Diesel Engines ◽  
High Speed ◽  
Scaling Laws ◽  
Fuel Injection ◽  
Pollutant Emissions ◽  
Liquid Penetration ◽  
Spray Characteristics ◽  
Penetration Length ◽  
Air Mixing

Scaled model experiments can greatly reduce the cost, time and energy consumption in diesel engine development, and the similarity of spray characteristics has a primary effect on the overall scaling results of engine performance and pollutant emissions. However, although so far the similarity of spray characteristics under the non-evaporating condition has been studied to some extent, researches on scaling the evaporating sprays are still absent. The maximum liquid penetration length has a close relationship with the spray evaporation processes and is a key parameter in the design of diesel engine spray combustion system. In this article, the similarity of maximum liquid penetration length is theoretically derived based on the hypotheses that the spray evaporation processes in modern high-pressure common rail diesel engines are fuel–air mixing controlled and local interphase transport controlled, respectively. After verifying that the fuel injection rates are perfectly scaled, the similarity of maximum liquid penetration length in evaporating sprays is studied for three scaling laws using two nozzles with hole diameter of 0.11 and 0.14 mm through the high-speed diffused back-illumination method. Under the test conditions of different fuel injection pressures, ambient temperatures and densities, the lift-off law and speed law lead to a slightly increased maximum liquid penetration length, while the pressure law can well scale the maximum liquid penetration length. The experimental results are consistent with the theoretical analyses based on the hypothesis that the spray evaporation processes are fuel–air mixing controlled, indicating that the local interphase transports of energy, momentum and mass on droplet surface are not rate-controlled steps with respect to spray evaporation processes.

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