Search results for "Friction."
showing 10 items of 350 documents
A New Simple Friction Model for S. I. Engine
2009
Internal combustion engine modeling is nowadays a widely employed tool for modern engine development. Zero and mono dimensional models of the intake and exhaust systems, combined with multi-zone combustion models, proved to be reliable enough for the accurate evaluation of in-cylinder pressure, which in turn allow the estimation of the engine performance in terms of indicated mean effective pressure (IMEP). In order to evaluate the net engine output, both the torque dissipation due to friction and the energy drawn by accessories must be taken into consideration, hence a model for the friction mean effective pressure (FMEP) evaluation is needed. One of the most used models accounts for engin…
Simulation Study on the Use of Argon Mixtures in the Pressurized Motored Engine for Friction Determination
2020
Mechanical friction and heat transfer in internal combustion engines are two highly researched topics, due to their importance on the mechanical and thermal efficiencies of the engine. Despite the research efforts that were done throughout the years on both these subjects, engine modeling is still somewhat limited by the use of sub-models which do not fully represent the phenomena happening in the engine. Developing new models require experimental data which is accurate, repeatable and which covers wide range of operation. In SAE 2018-01-0121, the conventional pressurized motored method was investigated and compared with other friction determination methods. The pressurized motored method p…
Cyclic Delamination Analysis: Experimental and Cohesive-Frictional interface Finite Element Modelling
2011
Multi-body numerical simulation of the distribution drive system in an internal combustion engine
2008
V clanku je predstaven vyvoj metodiky pro vypocet dynamiky mechanismu motoroveho rozvodu. Vyuzity jsou techniky simulaci vicehmotovych soustav; pouzit byl software AVL/Tycon. Objektem vyzkumu byl vliv pracovnfho rezimu motoru na dynamiku retezoveho rozvodu s jednim (SOHC) a dvema (DOHC) vackovymi hndeli v hiave motoru. Analyza obsahuje dukaz, ze retezovy prevod zavadi (di'ky kinematickemu zaberu) vysokou frekvenci s velmi malou amplitudou v porovnani s harmonickymi frekvencemi od externi sil. Metodika umozhuje urdt zati'zeni vstupni'ho a pomocnych hridelu, zatizeni na strukturu motoru indukovane pres operne a napmaci kladky. Diky tomu se predstavena metodika stava vyznamnym nastrojem pro pr…
An optimization procedure for the friction stir welding FEM model of corner fillet joints
2012
Friction stir welding (FSW) is an energy efficient and environmentally "friendly" (no fumes, noise, or sparks) welding process, during which the sheets are welded together in a solid-state joining process. FSW is mature for simple configurations but a significant lack of knowledge is found when dealing with different designs such as T-sections, box sections and corner welds. Although the latter joint morphology has traditionally been considered unfeasible for the process, it seems to have a great potential to be used also for T-joint configurations, a recurrent design pattern in transport applications. A specific tool has been developed and a set of experimental welds has been produced with…
Constant Heat Input Friction Stir Welding of Variable Thickness AZ31 Sheets Through In-Process Tool Rotation Control
2019
Tailored blanks characterized by variable thickness were friction stir welded (FSWed) with the aim to obtain constant joint properties along the weld seam, regardless of the thickness change. To pursue this goal, the heat input was kept constant by in-process control of tool rotation. A dedicated numerical model of the process was used to determine the tool rotation values as a function of the sheet thickness. The mechanical properties and the microstructure of the FSWed joints, produced with varying process parameters, were studied. It was found that the proposed approach can produce joints with uniform properties along the weld line in terms of stress–strain curve shape, joint strength, e…
Lightweight Alloys Recycling and Processing through Innovative Friction Based Direct Technologies
In the last decades, the use of lightweight alloys has been spreading in almost any industrial field thanks to the relevant weight reduction allowed by the use of such materials. On the other hand, aluminium alloys are characterized by high-energy demands primary production cycles that are responsible for a relevant share of the global CO2 emissions. In order to limit and reverse such phenomenon, putting in place strategies to keep the material in the circle over multiple life cycles is mandatory and the concepts of circular economy, closed loop society and industrial symbiosis are progressively gathering more and more pace. Nevertheless, metal scraps are often mainly composed of chips resu…
Progresses in multi-materials billet manufacturing out of metal scraps through friction stir consolidation
2023
Abstract. The evolution of Friction Stir Consolidation (FSC) from recycling towards upcycling technique proved to be one of the excellent solid-state methods for manufacturing functionally graded billets. Multi-material Functional Graded Materials (FGMs) represent a novel class of materials characterized by a gradual change in properties and functions which can be tailored to enhance components performance. Manufacturing techniques play a critical role in achieving the designed compositional and microstructural distribution. Specifically, FSC allows the manufacturing of FGM billets out of metallic chips; the mixing of different metallic chips offers mutually exclusive mechanical properties …
An experimental study for the characterization of fluid dynamics and heat transport within the spacer-filled channels of membrane distillation modules
2018
Abstract The thermo-fluid dynamic behavior of spacer-filled channels for membrane distillation was investigated experimentally. Several different geometry were investigated thanks to customized reference spacers manufactured using a 3D printer. In particular, two sets of experiments were conducted: in the first set, cylindrical filaments were orthogonally arranged and the flow attack angle was made to vary from 0o to 90o; in the second set, the flow attack angle was kept symmetrical and the filament angle was made to vary from 30° to 150°. Each spacer was tested for Reynolds numbers between 200 and 900 in the hot channel, while maintaining a constant temperature difference of 13 °C between …
Tool Path Design in Friction Stir Welding of AA6082-T6 Aluminium Alloy
2007
In the paper, a variation of the Friction Stir Spot Welding (FSSW) process has been considered. In particular, a particular tool path is given after the sinking phase nearby the initial penetration site. The process mechanics was highlighted and the joint strength was considered at the varying of the most relevant process parameters. Furthermore macro and micro analyses were developed in order to highlight the process mechanics and the local material microstructure evolution. The investigated technology appears a promising joining technique in order to develop effective spot joints.