Numerical Study on Thermal Performances of Multi Heat Source Heating System Using Butane for Electric Vehicle

In this study, a 3D numerical study of free ventilated room equipped with a discrete heat source was performed using the Finite Volume Method (FVM). To ensure good ventilation, two parallel openings were created in the room. A suction opening was located at the bottom of the left wall and another opening was located at the top of the opposite wall; the heat source was placed at various positions in order to compare the heating efficiency. The effects of Rayleigh number (103 ≤ Ra ≤ 106) for six heater positions was studied. The results focus on the impact of these parameters on the particle trajectories, temperature fields and on the heat transfer inside the room. It was found that the position of the heater has a dramatic effect on the behavior and topography of the flow in the room. When the heat source was placed on the wall with the suction opening, two antagonistic behaviors were recorded: an improvement in heat transfer of about 31.6%, compared to the other positions, and a low Rayleigh number against 22% attenuation for high Ra values was noted.

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Heat pump air conditioning system for pure electric vehicle at ultra-low temperature

Thermal Science ◽

10.2298/tsci1405667l ◽

2014 ◽

Vol 18 (5) ◽

pp. 1667-1672 ◽

Cited By ~ 2

Author(s):

Hai-Jun Li ◽

Guang-Hui Zhou ◽

An-Gui Li ◽

Xu-Ge Li ◽

Ya-Nan Li ◽

...

Keyword(s):

Low Temperature ◽

Electric Vehicle ◽

Heat Pump ◽

Air Conditioning ◽

Heating System ◽

Experimental Results ◽

Air Conditioning System ◽

Discharge Temperature ◽

Heating Capacity ◽

Environment Temperature

When the ordinary heat pump air conditioning system of a pure electric vehicle runs at ultra-low temperature, the discharge temperature of compressor will be too high and the heating capacity of the system will decay seriously, it will lead to inactivity of the heating system. In order to solve this problem, a modification is put forward, and an experiment is also designed. The experimental results show that in the same conditions, this new heating system increases more than 20% of the heating capacity; when the outside environment temperature is negative 20 degrees, the discharge temperature of compressor is below 60 degrees.

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Numerical Investigation of Mixed Convection and Entropy Generation in a Wavy-Walled Cavity Filled with Nanofluid and Involving a Rotating Cylinder

Entropy ◽

10.3390/e20090664 ◽

2018 ◽

Vol 20 (9) ◽

pp. 664 ◽

Cited By ~ 25

Author(s):

Ammar Alsabery ◽

Muneer Ismael ◽

Ali Chamkha ◽

Ishak Hashim

Keyword(s):

Heat Exchange ◽

Rayleigh Number ◽

Heat Source ◽

Mixed Convection ◽

Volume Fraction ◽

Numerical Study ◽

Rotational Velocity ◽

Geometrical Parameters ◽

Galerkin Finite Element ◽

Vertical Walls

This numerical study considers the mixed convection and the inherent entropy generated in Al 2 O 3 –water nanofluid filling a cavity containing a rotating conductive cylinder. The vertical walls of the cavity are wavy and are cooled isothermally. The horizontal walls are thermally insulated, except for a heat source segment located at the bottom wall. The dimensionless governing equations subject to the selected boundary conditions are solved numerically using the Galerkin finite-element method. The study is accomplished by inspecting different ranges of the physical and geometrical parameters, namely, the Rayleigh number ( 10 3 ≤ R a ≤ 10 6 ), angular rotational velocity ( 0 ≤ Ω ≤ 750 ), number of undulations ( 0 ≤ N ≤ 4 ), volume fraction of Al 2 O 3 nanoparticles ( 0 ≤ ϕ ≤ 0.04 ), and the length of the heat source ( 0.2 ≤ H ≤ 0.8 ) . The results show that the rotation of the cylinder boosts the rate of heat exchange when the Rayleigh number is less than 5 × 10 5 . The number of undulations affects the average Nusselt number for a still cylinder. The rate of heat exchange increases with the volume fraction of the Al 2 O 3 nanoparticles and the length of the heater segment.

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