On the mechanism of final heat transfer restoration at the transition to gas-like fluid at supercritical pressure: A description by CFD analyses

The aim of this investigation was to study automotive disc brake cooling characteristics experimentally using a specially developed spin rig and numerically using finite element (FE) and computational fluid dynamics (CFD) methods. All three modes of heat transfer (conduction, convection and radiation) have been analysed along with the design features of the brake assembly and their interfaces. The spin rig proved to be very valuable equipment; experiments enabled the determination of the thermal contact resistance between the disc and wheel carrier. The analyses demonstrated the sensitivity of this mode of heat transfer to clamping pressure. For convective cooling, heat transfer coefficients were measured and very similar results were obtained from spin rig experiments and CFD analyses. The nature of radiative heat dissipation implies substantial e ects at high temperatures. The results indicate substantial change of emissivity throughout the brake application. The influence of brake cooling parameters on the disc temperature has been investigated by FE modelling of a long drag brake application. The thermal power dissipated during the drag brake application has been analysed to reveal the contribution of each mode of heat transfer.

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Heat transfer study in rotating cascade using IR thermography and CFD analyses

Heat and Mass Transfer ◽

10.1007/s00231-007-0269-0 ◽

2007 ◽

Vol 44 (5) ◽

pp. 559-567 ◽

Cited By ~ 3

Author(s):

Lovrenc Novak ◽

Mitja Mori ◽

Mihael Sekavčnik

Keyword(s):

Heat Transfer ◽

Ir Thermography ◽

Cfd Analyses ◽

Transfer Study

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Numerical Analysis of Heat Transfer Test of Supercritical Water in a Tube Using the Three-Dimensional Two-Fluid Model Code

Volume 3: Thermal Hydraulics; Instrumentation and Controls ◽

10.1115/icone16-48690 ◽

2008 ◽

Cited By ~ 1

Author(s):

Takeharu Misawa ◽

Hiroyuki Yoshida ◽

Hidesada Tamai ◽

Kazuyuki Takase

Keyword(s):

Heat Transfer ◽

Fluid Model ◽

Three Dimensional ◽

Design Procedure ◽

Supercritical Pressure ◽

Thermal Design ◽

Energy Agency ◽

Pressure Region ◽

Two Fluid Model ◽

Two Fluid

The three-dimensional two-fluid model analysis code ACE-3D is developed in Japan Atomic Energy Agency for the thermal design procedure on two-phase flow thermal-hydraulics of light water-cooled reactors. In order to perform thermal hydraulic analysis of SCWR, ACE-3D is enhanced to supercritical pressure region. As a result, it is confirmed that transient change in subcritical and supercritical pressure region can be simulated smoothly using ACE-3D, that ACE-3D can predict the results of the past heat transfer experiment in the supercritical pressure condition, and that introduction of thermal conductivity effect of the wall restrains fluctuation of wall.

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CFD Aided Design of Heat Transfer Plates for Gasketed Plate Heat Exchangers

Volume 3: Engineering Systems; Heat Transfer and Thermal Engineering; Materials and Tribology; Mechatronics; Robotics ◽

10.1115/esda2014-20063 ◽

2014 ◽

Author(s):

Ece Özkaya ◽

Selin Aradag ◽

Sadik Kakac

Keyword(s):

Heat Transfer ◽

Pressure Drop ◽

Heat Exchangers ◽

Three Dimensional ◽

Separate Flow ◽

Working Fluid ◽

Number Range ◽

Plate Heat ◽

Pressure Distributions ◽

Cfd Analyses

In this study, three-dimensional computational fluid dynamics (CFD) analyses are performed to assess the thermal-hydraulic characteristics of a commercial Gasketed Plate Heat Exchangers (GPHEx) with 30 degrees of chevron angle (Plate1). The results of CFD analyses are compared with a computer program (ETU HEX) previously developed based on experimental results. Heat transfer plate is scanned using photogrammetric scan method to model GPHEx. CFD model is created as two separate flow zones, one for each of hot and cold domains with a virtual plate. Mass flow inlet and pressure outlet boundary conditions are applied. The working fluid is water. Temperature and pressure distributions are obtained for a Reynolds number range of 700–3400 and total temperature difference and pressure drop values are compared with ETU HEX. A new plate (Plate2) with corrugation pattern using smaller amplitude is designed and analyzed. The thermal properties are in good agreement with experimental data for the commercial plate. For the new plate, the decrease of the amplitude leads to a smaller enlargement factor which causes a low heat transfer rate while the pressure drop remains almost constant.

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