Experimental Research on Flow around a Cooling Fan Unit in a Engine Compartment Model of Construction Machinery.

This paper compares the performances of three Computational Fluid Dynamics (CFD) turbulence models, Reynolds Average Navier-Stokes (RANS), Detached Eddy Simulation (DES), and Large Eddy Simulation (LES), for simulating the flow field of a wheel loader engine compartment. The distributions of pressure fields, velocity fields, and vortex structures in a hybrid-grided engine compartment model are analyzed. The result reveals that the LES and DES can capture the detachment and breakage of the trailing edge more abundantly and meticulously than RANS. Additionally, by comparing the relevant calculation time, the feasibility of the DES model is proved to simulate the three-dimensional unsteady flow of engine compartment efficiently and accurately. This paper aims to provide a guiding idea for simulating the transient flow field in the engine compartment, which could serve as a theoretical basis for optimizing and improving the layout of the components of the engine compartment.

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A Mobile Robot with Omnidirectional Tracks—Design and Experimental Research

Applied Sciences ◽

10.3390/app112411778 ◽

2021 ◽

Vol 11 (24) ◽

pp. 11778

Author(s):

Mateusz Fiedeń ◽

Jacek Bałchanowski

Keyword(s):

Mobile Robot ◽

Experimental Research ◽

Mobile Systems ◽

Movement Trajectory ◽

Mobile Platforms ◽

Construction Machinery ◽

Drive Systems ◽

Small Robot ◽

And Control ◽

Design And Testing

This article deals with the design and testing of mobile robots equipped with drive systems based on omnidirectional tracks. These are new mobile systems that combine the advantages of a typical track drive with the advantages of systems equipped with omnidirectional Mecanum wheels. The omnidirectional tracks allow the robot to move in any direction without having to change the orientation of its body. The mobile robot market (automated construction machinery, mobile handle robots, mobile platforms, etc.) constantly calls for improvements in the manoeuvrability of vehicles. Omnidirectional drive technology can meet such requirements. The main aim of the work is to create a mobile robot that is capable of omnidirectional movement over different terrains, and also to conduct an experimental study of the robot’s operation. The paper presents the construction and principles of operation of a small robot equipped with omnidirectional tracks. The robot’s construction and control system, and also a prototype made with FDM technology, are described. The trajectory parameters of the robot’s operation along the main and transverse axes were measured on a test stand equipped with a vision-based measurement system. The results of the experimental research became the basis for the development and experimental verification of a static method of correcting deviations in movement trajectory.

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Design and Experimental Research of Magneto-Rheological Fluid Fan Clutch

Volume 2: 31st Design Automation Conference, Parts A and B ◽

10.1115/detc2005-84367 ◽

2005 ◽

Author(s):

Yuliang Shen ◽

Shaopu Yang ◽

Cunzhi Pan

Keyword(s):

Magnetic Fields ◽

Experimental Research ◽

Fundamental Principle ◽

Mr Fluid ◽

Shear Model ◽

Engine Cooling ◽

Cooling Fan ◽

Output Torque ◽

Novel Structure ◽

Magneto Rheological

The fundamental principle of MR fluid fan clutch in transmitting torque is analyzed, in the meantime, a shear model of MR clutch is proposed; MR fluid fan clutch having simple, novel structure is designed and made; At the same time, on the basis of experiments, the characteristic of velocity regulating of the clutch is studied in detail. The experimental results indicate that, compared with the shearing rate, the change of magnetic fields has a tremendous influence on the speed regulating characteristic of a fan clutch, and output torque of fan clutch can satisfy demand of engine cooling fan.

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Experimental Research on Rubber Compatibility of Drive Train oils used in Construction Machinery

Journal of Physics Conference Series ◽

10.1088/1742-6596/2125/1/012018 ◽

2021 ◽

Vol 2125 (1) ◽

pp. 012018

Author(s):

Haizhen An ◽

Min Liu ◽

Penghou Zhen ◽

Li Chen

Keyword(s):

Experimental Research ◽

Volume Change ◽

Drive Train ◽

Reliable Operation ◽

Change Rate ◽

Rubber Sheet ◽

Construction Machinery ◽

Before And After ◽

Hardness Change ◽

Train System

Abstract The compatibility of oil and rubber in the drive train system of construction machinery plays an important role in the safe and reliable operation of the system. In order to investigate the rubber compatibility of drive train system oil of construction machinery, the changes of rubber sheet volume and hardness before and after immersion of standard fluororubber (FKM2) and hydrogenated nitrile rubber (HNBR1) with 9 kinds of drive train system oil were tested. The results show that FKM2 has good rubber compatibility with drive train oil, and HNBR1 is only compatible with some drive train oil; The volume change rate and hardness change range of FKM2 are smaller than those of HNBR1.

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Experimental Research on Anti-rust Performance of Drive Train Oils Used in Construction Machinery

Journal of Physics Conference Series ◽

10.1088/1742-6596/2044/1/012038 ◽

2021 ◽

Vol 2044 (1) ◽

pp. 012038

Author(s):

Min Liu ◽

Haizhen An ◽

Penghou Zhen ◽

Li Chen

Keyword(s):

Experimental Research ◽

Drive Train ◽

Construction Machinery

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Secondary Transfer Effect of Contact

Social Psychology ◽

10.1027/1864-9335.40.2.55 ◽

2009 ◽

Vol 40 (2) ◽

pp. 55-65 ◽

Cited By ~ 146

Author(s):

Thomas F. Pettigrew

Keyword(s):

Cognitive Dissonance ◽

Experimental Research ◽

Intergroup Contact ◽

Transfer Effect ◽

Evaluative Conditioning ◽

Transfer Effects ◽

Secondary Transfer ◽

Primary Reduction

This paper reviews the evidence for a secondary transfer effect of intergroup contact. Following a contact’s typical primary reduction in prejudice toward the outgroup involved in the contact, this effect involves a further, secondary reduction in prejudice toward noninvolved outgroups. Employing longitudinal German probability samples, we found that significant secondary transfer effects of intergroup contact exist, but they were limited to specific outgroups that are similar to the contacted outgroup in perceived stereotypes, status or stigma. Since the contact-prejudice link is bidirectional, the effect is inflated when prior prejudice reducing contact is not controlled. The strongest evidence derives from experimental research. Both cognitive (dissonance) and affective (evaluative conditioning) explanations for the effect are offered.

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