G503 Experimental Research on the Performance of a Cooling Fan in a Construction Machinery's Engine Compartment Model

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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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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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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