FLOW BEHAVIOUR ANALYSIS ALONG AN ENGINE AIR INTAKE PIPE

2015 ◽  
Vol 76 (10) ◽  
Author(s):  
Zainal Abidin Kamarulbaharin ◽  
Salmiah Kasolang
Keyword(s):  
Combustion Engine ◽  
Pressure Ratio ◽  
Pressure Profile ◽  
Flow Behaviour ◽  
Intake Pipe ◽  
Pressure Profiles ◽  
Pressure Dynamics ◽  
Air Intake ◽  
Preliminary Study ◽  
Pipe Geometry

There is a concern with the flow behaviour inside the air intake pipe that affects the desirable pressure ratio for inflow into the cylinder of an internal combustion engine. Measurements of flow along the intake pipe are required to better understand the physics of the intake system. This paper focuses on investigating the dynamics of the pressure profile along the intake pipe. The methodology involves experimental work utilising a red oil manometer to measure the pressure. Results analysis is presented as graphs of gauge pressures against engine speeds. From experimental results, the pressure profiles along the intake pipe were similar at different engine speed settings and pipe lengths. It was observed that the values of gauge pressure were lowest at the pipe entrance and it continued to rise along the pipe until it reaches the intake valve.  This is a preliminary study looking into the effect of pipe geometry on the pressure dynamics.  

Numerical Investigation of Crosswind Effect on Different Rear Mounted Engine Installations

2014 ◽  
Author(s):  
Hairun Xie ◽  
Yadong Wu ◽  
Anjenq Wang ◽  
Hua Ouyang
Keyword(s):  
Flow Field ◽  
Total Pressure ◽  
Pressure Profile ◽  
Operating Conditions ◽  
Operating Characteristics ◽  
Close Coupling ◽  
Pressure Profiles ◽  
Air Intake ◽  
A Minor ◽  
Condition Assessments

The rear-mounted engine is widely used in business and regional jets. It is a “clean wing” design. The engine is mounted behind the wing, so that the inlet/outlet of the nacelle has a minor influence on the flow over the wing. The engine thrust line is close to the fuselage axis. As a result, the asymmetric yaw moment will be smaller when single engine stall occurs. Strict regulations and requirements were set by certification agencies to assess aircraft maneuver capability as well as engine operating characteristics. These regulations are mainly defined to evaluate structural strength, aerodynamics, & engine/aircraft performance. However, due to the nature of the complexity of the flow field at the air intake, the inlet compatibility of fuselage mounted engines becomes one of the most complicated & challenging items to meet FAR33 as well as FAR25 certification requirements, especially during cross wind operating conditions. This research paper discusses the inlet compatibility of rear-mounted aircraft engines with respect to the installed configuration and crosswind operating conditions. Models of two installed configurations, set by the relative position of engine to the fuselage and the wing were created. In each case, the engine inlet flow field was calculated at various ambient wind conditions. Comparisons of the total pressure profile at the air intake were made to assess the likelihood of flow separation at the inlet of engine. Inlet distortion levels of corresponding total pressure profiles were calculated for each operating and installed condition. Assessments are made based on intensive usage of CFD analysis of different engine installations and operating conditions. The flow field information obtained by CFD calculation reveals a close coupling phenomenon exists among engine installations, cross wind, and inlet capability.

scholarly journals Recent progress in battery electric vehicle noise, vibration, and harshness

2021 ◽  
Vol 104 (1) ◽  
pp. 003685042110052
Author(s):  
Xia Hua ◽  
Alan Thomas ◽  
Kurt Shultis
Keyword(s):  
Electric Vehicle ◽  
Recent Progress ◽  
Combustion Engine ◽  
Automatic Transmission ◽  
Battery Electric Vehicle ◽  
Vehicle Noise ◽  
Conventional Vehicle ◽  
Transfer Case ◽  
Air Intake ◽  
Noise Vibration

As battery electric vehicle (BEV) market share grows so must our understanding of the noise, vibration, and harshness (NVH) phenomenon found inside the BEVs which makes this technological revolution possible. Similar to the conventional vehicle having encountered numerous NVH issues until today, BEV has to face many new and tough NVH issues. For example, conventional vehicles are powered by the internal combustion engine (ICE) which is the dominant noise source. The noises from other sources were generally masked by the combustion engine, thus the research focus was on the reduction of combustion engine while less attention was paid to noises from other sources. A BEV does not have ICE, automatic transmission, transfer case, fuel tank, air intake, or exhaust systems. In their place, there is more than enough space to accommodate the electric drive unit and battery pack. BEV is quieter without a combustion engine, however, the research on vehicle NVH is even more significant since the elimination of the combustion engine would expose many noise behaviors of BEV that were previously ignored but would now seem clearly audible and annoying. Researches have recently been conducted on the NVH of BEV mainly emphasis on the reduction of noise induced by powertrain, tire, wind and ancillary system and the improvement of sound quality. This review paper will focus on recent progress in BEV NVH research to advance the BEV systems in the future. It is a review for theoretical, computational, and experimental work conducted by both academia and industry in the past few years.

scholarly journals Propagation of radiosonde pressure sensor errors to ozonesonde measurements

2014 ◽  
Vol 7 (1) ◽  
pp. 65-79 ◽  
Author(s):  
R. M. Stauffer ◽  
G. A. Morris ◽  
A. M. Thompson ◽  
E. Joseph ◽  
G. J. R. Coetzee ◽  
...  
Keyword(s):  
Pressure Sensor ◽  
Atmospheric Pressure ◽  
Pressure Profile ◽  
Mixing Ratio ◽  
Concentration Cell ◽  
Pressure Profiles ◽  
Dependent Variables ◽  
Sensor Errors ◽  
Subsequent Addition ◽  
Total Column

Abstract. Several previous studies highlight pressure (or equivalently, pressure altitude) discrepancies between the radiosonde pressure sensor and that derived from a GPS flown with the radiosonde. The offsets vary during the ascent both in absolute and percent pressure differences. To investigate this problem further, a total of 731 radiosonde/ozonesonde launches from the Southern Hemisphere subtropics to northern mid-latitudes are considered, with launches between 2005 and 2013 from both longer term and campaign-based intensive stations. Five series of radiosondes from two manufacturers (International Met Systems: iMet, iMet-P, iMet-S, and Vaisala: RS80-15N and RS92-SGP) are analyzed to determine the magnitude of the pressure offset. Additionally, electrochemical concentration cell (ECC) ozonesondes from three manufacturers (Science Pump Corporation; SPC and ENSCI/Droplet Measurement Technologies; DMT) are analyzed to quantify the effects these offsets have on the calculation of ECC ozone (O3) mixing ratio profiles (O3MR) from the ozonesonde-measured partial pressure. Approximately half of all offsets are > ±0.6 hPa in the free troposphere, with nearly a third > ±1.0 hPa at 26 km, where the 1.0 hPa error represents ~ 5% of the total atmospheric pressure. Pressure offsets have negligible effects on O3MR below 20 km (96% of launches lie within ±5% O3MR error at 20 km). Ozone mixing ratio errors above 10 hPa (~ 30 km), can approach greater than ±10% (> 25% of launches that reach 30 km exceed this threshold). These errors cause disagreement between the integrated ozonesonde-only column O3 from the GPS and radiosonde pressure profile by an average of +6.5 DU. Comparisons of total column O3 between the GPS and radiosonde pressure profiles yield average differences of +1.1 DU when the O3 is integrated to burst with addition of the McPeters and Labow (2012) above-burst O3 column climatology. Total column differences are reduced to an average of −0.5 DU when the O3 profile is integrated to 10 hPa with subsequent addition of the O3 climatology above 10 hPa. The RS92 radiosondes are superior in performance compared to other radiosondes, with average 26 km errors of −0.12 hPa or +0.61% O3MR error. iMet-P radiosondes had average 26 km errors of −1.95 hPa or +8.75 % O3MR error. Based on our analysis, we suggest that ozonesondes always be coupled with a GPS-enabled radiosonde and that pressure-dependent variables, such as O3MR, be recalculated/reprocessed using the GPS-measured altitude, especially when 26 km pressure offsets exceed ±1.0 hPa/±5%.

Use of an Integrated Approach for Analysis and Design of Turbocharged Internal Combustion Engine

2021 ◽  
Author(s):  
Thiago Ebel ◽  
Mark Anderson ◽  
Parth Pandya ◽  
Mat Perchanok ◽  
Nick Tiney ◽  
...  
Keyword(s):  
Internal Combustion Engine ◽  
Combustion Engine ◽  
Early Stage ◽  
Pressure Ratio ◽  
Integrated Approach ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Dynamics Simulation ◽  
Analysis And Design ◽  
Performance Requirements

Abstract When developing a turbocharged internal combustion engine, the choice of turbocharger is usually based on designer experience and existing hardware. However, proper turbocharger design relies on matching the compressor and turbine performance to the engine requirements so that parameters such as boost and back pressure, compressor pressure ratio, and turbine inlet temperatures meet the needs of the engine without exceeding its allowable operating envelope. Therefore, the ultimate measure of a successful turbocharger design is how well it is matched to an engine across various operating conditions. This, in turn, determines whether a new turbocharger is required, or an existing solution can be used. When existing turbocharger solutions are not viable, the engine designer is at a loss on how to define a new turbocharger that meets the desired performance requirements. A common approach in industry has been to scale the performance of an existing turbocharger (compressor and turbine maps) and take these requirements for Original Equipment Manufacturers to possibly match it with a real machine. However, the assumptions made in a basic scaling process are quite simplistic and generally not satisfactory in this situation. A better approach would be to use a validated meanline model for a compressor and turbine instead, allowing to perform an actual preliminary design of such components. Such approach allows to link the engine performance requirements in a very early stage of te component design project and it guides the designer for the design decisions, such as rotor size, variable geometry nozzles, diameter, or shroud trims and others. Therefore, a feasible solution is more likely with design less iterations. This paper describes a methodology for an integrated approach to design and analyze a turbocharged internal combustion engine using commercially available state-of-the-art 1D gas dynamics simulation tool linked to two powerful turbomachinery meanline programs. The outputs of this analysis are detailed performance data of the engine and turbocharger at different engine operating conditions. Two case studies are then presented for a 10-liter diesel truck engine. The first study demonstrates how the programs are used to evaluate an existing engine and reverse engineer an existing turbocharger based only on the available performance maps. Then a second study is done using a similar approach but redesigning a new turbocharger (based on the reverse engineered one) for an increased torque output of the same engine.

Research on the Algorithm of Measurement Path Planning for Inner Wall of Air-Intake Pipe Based on Spraying Robot System

2017 ◽  
Vol 31 (09) ◽  
pp. 1759018 ◽  
Author(s):  
Zhiqiang Chao ◽  
Fei Wang ◽  
Chuanqing Zhang ◽  
Huaying Li ◽  
Feng Wang
Keyword(s):  
Path Planning ◽  
Plane Curve ◽  
Displacement Sensor ◽  
Sensor Technology ◽  
Arc Length ◽  
Robot System ◽  
Intake Pipe ◽  
Different Types ◽  
Air Intake ◽  
Measurement Path

To solve the problems with spraying over the inner wall of air-intake pipe, this paper introduces an algorithm of measurement path planning based on the spraying robot system and the laser displacement sensor technology. Scanning measurement path planning is the premise and basis of model construction and spray. Traditional methods, such as arc length extrapolation and polynomial are applicable only for the measurement of a plane curve with finite maximum curvature. Drawing references from existing method, this paper focuses on the pre-scanning measurement method for different types of cross-section curves. Algorithm simulation and model reconstruction show that this study solves the problem of collision avoidance for scanning measurement of the inner wall of air-intake pipe.

With the Backlash Dynamics Simulation of a Crank-Slider Mechanism of the Internal Combustion Engine

2012 ◽  
Vol 215-216 ◽  
pp. 1081-1084
Author(s):  
Shao Jun Bo ◽  
Kui Ji ◽  
Juan Tian
Keyword(s):  
System Dynamics ◽  
Combustion Engine ◽  
Dynamics Simulation ◽  
Kinematic Pair ◽  
Body System ◽  
Nonlinear Characteristics ◽  
Preliminary Study ◽  
Multi Body ◽  
Dynamics Models ◽  
Crank Mechanism

On the basis of flexible multi-body system dynamics theory, we built flexible multi-body system dynamics models which include a backlash, and to a slider-crank mechanism as the research object, we made a preliminary study on the effect on the flexible components and the backlash of the kinematic pair on mechanical system dynamics characteristics. To consider the backlash of the kinematic pair and component of flexible space can show a preliminary research on the dynamic simulation, and focus on the backlash, friction and gravity field to influence in the dynamic characteristics of the system. The simulation results show that, due to the existence of backlash made the two components frequent collision in the process of the stretching, clearance, flexible and friction are closed, make the system nonlinear characteristics increased.

Patterns and Reduced-order Reconstruction of Impinging Wiping Jet Pressure Profile Fluctuation Using Proper Orthogonal Decomposition

2021 ◽  
Author(s):  
Le Quang Phan ◽  
Andrew Johnstone ◽  
P. Buyung Kosasih ◽  
Wayne Renshaw
Keyword(s):  
Proper Orthogonal Decomposition ◽  
Jet Impingement ◽  
Pressure Profile ◽  
Orthogonal Decomposition ◽  
Maximum Pressure ◽  
Frequency Spectra ◽  
Reduced Order ◽  
Order Reconstruction ◽  
Pressure Profiles ◽  
Proper Orthogonal

Abstract Wiping jet impingement pressure is important in controlling the coating mass (thickness) and influencing the smoothness of the thin metallic coating produced in continuous galvanizing lines (CGLs). However, the fluctuation of the impingement pressure profile that directly impacts the coating smoothness has not been adequately understood. To study key features of the impingement pressure fluctuation, the instantaneous impingement pressure profiles obtained from Large Eddy Simulations were analyzed using Proper Orthogonal Decomposition (POD). Dominant fluctuation modes of pressure profiles can be differentiated from the energy contents of the modes corresponding to different jet types namely mixing, non-mixing, and transitional mixing jet. The dominant modes of mixing jets in the wiping region contain comparable strength of all modes (flapping, pulsing, and out-of-phase multi pulsing). Non-mixing jets do not show discernable fluctuation modes and transitional mixing jets show pulsing and flapping modes only. Additionally, instantaneous maximum pressure gradient and their location were determined from the reduced-order reconstruction of the pressure profiles. From the analysis, frequency spectra of the magnitude and location fluctuations of the maximum pressure gradients associated with each of the jet types can be clearly distinguished. This is a knowledge that may be helpful for CGL operators in the operation of wiping jets.

Preliminary Study of the Solid Powder Combustion Engine

2013 ◽  
Vol 13 (12) ◽  
pp. 2336-2340
Author(s):  
Tao Song Lei ◽  
Liu Huran ◽  
Lin Jie
Keyword(s):  
Combustion Engine ◽  
Preliminary Study ◽  
Powder Combustion

The Effects of Oil Supply Pressure at different Groove Position on Temperature and Pressure Profile in Journal Bearing

2013 ◽  
Vol 66 (3) ◽  
Author(s):  
Mohamad Ali Ahmad ◽  
Salmiah Kasolang ◽  
R. S. Dwyer-Joyce ◽  
Aidah Jumahat
Keyword(s):  
Journal Bearing ◽  
Pressure Profile ◽  
Diameter Ratio ◽  
Radial Load ◽  
Oil Supply ◽  
Supply Pressure ◽  
Pressure Profiles ◽  
Hydrodynamic Journal Bearing ◽  
Temperature And Pressure ◽  
Length To Diameter Ratio

The effects of oil supply pressure on the temperature and pressure at different groove locations on a hydrodynamic journal bearing were investigated. A journal with a diameter of 100 mm and a ½ length-to-diameter ratio was used. The supply pressure was set to 0.2, 0.5, and 0.7 MPa at seven different groove locations, namely, -45°, -30°, -15°, 0°, +15°, +30°, and +45°. Temperature and pressure profiles were measured at speed values of 300, 500, and 800 rpm with 10 kN radial load. The results show that the change in oil supply pressure simultaneously reduced the temperature and increased the pressure profile.

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