Turbocharged SI-Engine Simulation With Cold and Hot-Measured Turbocharger Performance Maps

2012 ◽  
Author(s):  
Habib Aghaali ◽  
Hans-Erik Ångström
Keyword(s):  
Heat Transfer ◽  
Physical Reality ◽  
Si Engine ◽  
One Dimensional ◽  
Engine Simulation ◽  
Simulation Based ◽  
The Common ◽  
The Difference ◽  
Heat Transfers ◽  
Variable Valve

Heat transfer within the turbocharger is an issue in engine simulation based on zero and one-dimensional gas dynamics. Turbocharged engine simulation is often done without taking into account the heat transfer in the turbocharger. In the simulation, using multipliers is the common way of adjusting turbocharger speed and parameters downstream of the compressor and upstream of the turbine. However, they do not represent the physical reality. The multipliers change the maps and need often to be different for different load points. The aim of this paper is to simulate a turbocharged engine and also consider heat transfer in the turbocharger. To be able to consider heat transfer in the turbine and compressor, heat is transferred from the turbine volute and into the compressor scroll. Additionally, the engine simulation was done by using two different turbocharger performance maps of a turbocharger measured under cold and hot conditions. The turbine inlet temperatures were 100 and 600°C, respectively. The turbocharged engine experiment was performed on a water-oil-cooled turbocharger (closed waste-gate), which was installed on a 2-liter gasoline direct-injected engine with variable valve timing, for different load points of the engine. In the work described in this paper, the difference between cold and hot-measured turbocharger performance maps is discussed and the quantified heat transfers from the turbine and to/from the compressor are interpreted and related to the maps.

Analysis of Variable Intake Runner Lengths and Intake Valve Open Timings on Engine Performances

2014 ◽  
Vol 663 ◽  
pp. 336-341 ◽  
Author(s):  
Mohd Farid Muhamad Said ◽  
Zulkarnain Abdul Latiff ◽  
Aminuddin Saat ◽  
Mazlan Said ◽  
Shaiful Fadzil Zainal Abidin
Keyword(s):  
Engine Performance ◽  
Intake Manifold ◽  
Intake Valve ◽  
Si Engine ◽  
Engine Simulation ◽  
Engine Model ◽  
Optimum Parameters ◽  
Comparison Results ◽  
Variable Valve ◽  
Engine Development

In this paper, engine simulation tool is used to investigate the effect of variable intake manifold and variable valve timing technologies on the engine performance at full load engine conditions. Here, an engine model of 1.6 litre four cylinders, four stroke spark ignition (SI) engine is constructed using GT-Power software to represent the real engine conditions. This constructed model is then correlated to the experimental data to make sure the accuracy of this model. The comparison results of volumetric efficiency (VE), intake manifold air pressure (MAP), exhaust manifold back pressure (BckPress) and brake specific fuel consumption (BSFC) show very well agreement with the differences of less than 4%. Then this correlated model is used to predict the engine performance at various intake runner lengths (IRL) and various intake valve open (IVO) timings. Design of experiment and optimisation tool are applied to obtain optimum parameters. Here, several configurations of IRL and IVO timing are proposed to give several options during the engine development work. A significant improvement is found at configuration of variable IVO timing and variable IRL compared to fixed IVO timing and fixed IRL.

scholarly journals Modulated oscillations in many dimensions

2013 ◽  
Vol 371 (1984) ◽  
pp. 20110551 ◽  
Author(s):  
S. C. Olhede
Keyword(s):  
Physical Oceanography ◽  
Time Varying ◽  
Signal Component ◽  
One Dimensional ◽  
The Common ◽  
The Difference ◽  
Common Signal ◽  
Multivariate Signals ◽  
Special Case ◽  
Signal Models

Modulated oscillations are described via their time-varying amplitude and frequency. For multivariate signals, there is structure in the signal beyond this local amplitude and frequency defined for each signal component, in turn describing the commonality of the components. The multivariate structure encodes how the common oscillation is present in each component signal. This structure will also be evolving. I review the special case of the representation of both bivariate and trivariate oscillations. Additionally, existing results on the general multivariate oscillation are covered. I discuss the difference between a model of a multivariate oscillation compared with other common signal models of phenomena observed in several channels, and how their properties are different. I show how for the multivariate signal the global dimensionality of the signal is built up from local one-dimensional contributions, and introduce the purely unidirectional signal, to quantify how any given signal is different from the closest such signal. I illustrate the properties of the derived representation of the multivariate signal with synthetic examples, and discuss the representation of data from observations in physical oceanography.

Heat Transfer by Conduction and Radiation in a One-Dimensional Absorbing, Emitting and Anisotropically-Scattering Medium

1980 ◽  
Vol 102 (2) ◽  
pp. 303-307 ◽  
Author(s):  
W. W. Yuen ◽  
L. W. Wong
Keyword(s):  
Heat Transfer ◽  
Anisotropic Scattering ◽  
Total Heat ◽  
Approximation Technique ◽  
Dimensional System ◽  
General Effect ◽  
Total Heat Transfer ◽  
One Dimensional ◽  
The Common ◽  
Scattering Material

Heat transfer by simultaneous conduction and radiation in an absorbing, emitting and anisotropically-scattering material is investigated theoretically. Consideration is given to a one-dimensional system bounded by two parallel gray, diffuse and isothermal walls. Assuming a physical model of linear-anisotropic scattering, the resulting integral-differential equation is solved by a successive approximation technique similar to the method of undetermined parameters. The solution method is demonstrated to be relatively simple and yields solution converging qucikly to the exact results. Results show that for the present one-dimensional system, the common approach of treating the total heat transfer as a simple addition of separate independent contributions from conduction and radiation is quite inaccurate for certain cases. This approach is thus ineffective in illustrating the general effect of scattering. Both the scattering albedo and the forward-backward scattering parameters are shown to have some interesting effects on the total heat transfer and the medium’s temperature. The magnitude of these effects depends on the surface emissivity of the two boundaries.

Numerical Project for the Undergraduate Heat Transfer Course

2017 ◽  
Author(s):  
Dani Fadda
Keyword(s):  
Heat Transfer ◽  
Solid Body ◽  
Three Dimensional ◽  
Engineering Curriculum ◽  
One Dimensional ◽  
Conduction Heat Transfer ◽  
Heat Transfer Simulation ◽  
The Difference ◽  
Dimensional Simulation ◽  
Classroom Time

A numerical simulation project, described in this paper, was assigned in an undergraduate heat transfer course in the mechanical engineering curriculum. This project complemented the heat transfer lecture course and its corresponding heat transfer lab. It was used to help students visualize and better understand the difference between conduction heat transfer which occurs within a three-dimensional solid body and the convection and/or radiation which occur at the surface of the solid body. It also allowed the students to generate and compare results of one dimensional heat transfer calculations to three dimensional simulation results. The project contained well defined deliverables and an open-ended deliverable which allowed students to be creative. It gave the students reason to discuss the course outside the classroom. It allowed students to use SolidWorks heat transfer simulation and manage a MATLAB script without taking classroom time. It was appreciated and enjoyed by the students.

Turbulence Model Dependencies on Conjugate Simulation of Flow and Heat Conduction

2007 ◽  
Author(s):  
Takahiro Bamba ◽  
Takashi Yamane ◽  
Yoshitaka Fukuyama
Keyword(s):  
Heat Transfer ◽  
Heat Conduction ◽  
Turbulence Model ◽  
Flow Simulation ◽  
Turbulence Models ◽  
Jet Impingement ◽  
Turbine Cascade ◽  
Turbulent Transition ◽  
Simulation Based ◽  
The Common

This paper discusses the influences of the turbulence model selection on the heat transfer prediction in the conjugate simulation of flow and heat conduction. It is known that the heat transfer prediction by the flow simulation based on RANS is dependent upon the turbulence model. Common difficulties are the anomalous production of turbulent kinetic energy in a flow with large rates of strain and the laminar-turbulent transition, both of which are persistent aspects in typical turbine cascade flow. Similar and possibly greater impact is expected when these turbulence models are applied to the conjugate simulation of flow and heat conduction. An anomaly treatment called a time-scale bound is applied to the low Reynolds number k-ω and the SST turbulence models installed in the common CFD platform UPACS. The turbulence model dependencies on the conjugate simulation of flow and heat conduction are investigated in an axisymmetric turbulent jet impingement and the 2D turbine cascade vanes.

Sensitivity of Temperature Rise in a Rolling Tire to the Viscoelastic Properties of the Tire Components

1987 ◽  
Vol 15 (2) ◽  
pp. 123-133 ◽  
Author(s):  
C. W. Beringer ◽  
Y. D. Kwon ◽  
D. C. Prevorsek
Keyword(s):  
Heat Transfer ◽  
Steady State ◽  
Temperature Change ◽  
Heat Generation ◽  
Temperature Rise ◽  
Viscoelastic Properties ◽  
Sensitivity Coefficient ◽  
Heat Generation Rate ◽  
One Dimensional ◽  
The Difference

Abstract The sensitivity coefficient of tire temperature to heat generation rate of tire compounds is derived based on a simplified tire geometry and one-dimensional heat transfer approximation. This provides a simple and quick means for estimating the magnitude of change in the steady-state tire rolling temperature resulting from the difference in the heat generation rates of cord and rubber in the tire. The use of this sensitivity coefficient in several tire temperature analyses gave good indications of the temperature change. Shortcomings and limitations of the approach are also discussed.

Ḥadith ‘Āishah fī Man’i al-Nisā’ Min al-Masājid; Niqāsh ‘Ulamā’ Bangladesh Ḥaulahu

2020 ◽  
Vol 9 (1) ◽  
pp. 97-115
Author(s):  
Syed Mahmudul Hasan
Keyword(s):  
Analytical Method ◽  
Inductive Method ◽  
The Common ◽  
The Difference ◽  
Common Situation

The Narration of Aisyah (May Allah be pleased with her), is the main focus of the controversy among Bangladeshi scholars on the issue of women's prayer in the mosque. The reason for the dispute is that a group of them issued the ruling based on the phenomenon of the text, and the others explained the ruling of Hadith according to the common situation in the society. If the circumstances change, the ruling will change along with it, because the originality of the issue is permissible, that is proven from other texts. This research adopts an inductive method to survey the Prophetic hadiths that talk about the prayer of women in the Mosque in terms of permissibility and prohibition and analytical method to analyze the difference in opinion of Bangladeshi scholars related to this issue. The research finds that the ruling of Shari’ah is a process that is continuous and permanent. But in necessity and emergency, it has the notion of flexibility and explanation. In the issue of women’s presence in the mosque, they should be allowed if they abide by the suggestions of Prophet (s) and should not if they don’t. So, Prohibition is not from the prophet (s), but it is from their obedience to the ruling.

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