Design, synthesis and nucleate boiling performance assessment of hybrid micro-nano porous surfaces for thermal management of concentrated photovoltaics (CPV)

2019 ◽  
Vol 195 ◽  
pp. 1056-1066 ◽  
Author(s):  
Shoukat Alim Khan ◽  
Nurettin Sezer ◽  
Salman Ismail ◽  
Muammer Koç
Keyword(s):  
Performance Assessment ◽  
Thermal Management ◽  
Nucleate Boiling ◽  
Design Synthesis ◽  
Porous Surfaces ◽  
Concentrated Photovoltaics

Parametric Study of Pool Boiling on Horizontal Highly Conductive Microporous Coated Surfaces

2007 ◽  
Vol 129 (11) ◽  
pp. 1465-1475 ◽  
Author(s):  
Chen Li ◽  
G. P. Peterson
Keyword(s):  
Coating Thickness ◽  
Copper Wire ◽  
Pool Boiling ◽  
Nucleate Boiling ◽  
Experimental Investigations ◽  
Phase Flow ◽  
Porous Coatings ◽  
Surface Conditions ◽  
Porous Surfaces ◽  
Coated Surfaces

To better understand the mechanisms that govern the behavior of pool boiling on horizontal highly conductive microporous coated surfaces, a series of experimental investigations were designed to systematically examine the effects of the geometric dimensions (i.e., coating thickness, volumetric porosity, and pore size, as well as the surface conditions of the porous coatings) on the pool-boiling performance and characteristics. The study was conducted using saturated distilled water at atmospheric pressure (101kPa) and porous surfaces fabricated from sintered isotropic copper wire screens. For nucleate boiling on the microporous coated surfaces, two vapor ventilation modes were observed to exist: (i) upward and (ii) mainly from sideways leakage to the unsealed sides and partially from the center of porous surfaces. The ratio of the heater size to the coating thickness, the friction factor of the two-phase flow to single-phase flow inside the porous coatings, as well as the input heat flux all govern the vapor ventilation mode that occurs. In this investigation, the ratio of heater size to coating thickness varies from 3.5 to 38 in order to identify the effect of heater size on the boiling characteristics. The experimental results indicate that the boiling performance and characteristics are also strongly dependent on the volumetric porosity and mesh size, as well as the surface conditions when the heater size is given. Descriptions and discussion of the typical boiling characteristics; the progressive boiling process, from pool nucleate boiling to film boiling; and the boiling performance curves on conductive microporous coated surfaces are all systematically presented.

Integrated Eco-Thermal Management for Aerospace

2005 ◽  
Author(s):  
Lev Reznikov
Keyword(s):  
Heat Transfer ◽  
Thermal Management ◽  
High Performance ◽  
Waste Heat ◽  
Space Station ◽  
Nucleate Boiling ◽  
High Heat ◽  
Novel Technologies ◽  
Related Substances ◽  
Nucleation Sites

Thermal Management System developed for aerospace carriers (missile, aircraft, space station), bounds processes of generation and dissipation, transfer and conversion of power, refrigeration, and of bio-metabolism related substances. Local ecosystem of the carrier combines technological and biological subsystems, interacting with internal and outer spaces. The conceptual IETM System performs recovery of waste thermal energy, generation of “free” refrigeration, and recovery of byproducts into safe coolants (ammonia - water). Thermal Management solutions include novel technologies of intensification of the heat transfer and of conversion of the waste resources into refrigeration for extension of cooling capabilities for high heat radars, lasers and microwave generators. The IETM includes Vacuum-Evaporative Refrigeration (VER) utilizing “free natural” vacuum and waste heat-activated refrigeration circuits. VER generates ~1000 Btu of “free” cold per pound of wastewater or ammonia. The introduced high performance microstructure of compound electrohydrodynamic (EHD) boundary microsystems intensifies nucleate boiling, preventing dryout. The coils of the microwires adjoin to the boiling surface and form precision microstructure of heat sink with microchannels between the coils and the surface. The microcavities form the active bubbling nucleation sites along the spiral zones of contacts of the microwires and basic surfaces. The fins-microelectrodes develop additional heat transfer surface and evenly distributed spiral zones of the nucleation sites. Like fibers of a fine wick, the electric forces in EHD capillary structures of the microelectrodes retain the liquid and push out generated vapor bubbles from the surface. Good manufacturability and performance of novel MEMS are based on well-developed materials and common winding technology “borrowed” from electrotechnical industry. Conversion of waste resources into refrigeration and EHD activation of boiling allow meeting strong limitations in weight, reliability and consumption of energy. These conceptual approaches provide diversities in refrigeration capabilities for IETM.

Enhanced nucleate boiling on copper micro-porous surfaces

2010 ◽  
Vol 36 (10) ◽  
pp. 780-792 ◽  
Author(s):  
Mohamed S. El-Genk ◽  
Amir F. Ali
Keyword(s):  
Nucleate Boiling ◽  
Porous Surfaces

Nucleate boiling of low-concentration alcohol aqueous solutions for the development of thermal management systems in space

2007 ◽  
Vol 19 (3-4) ◽  
pp. 141-143 ◽  
Author(s):  
Haruhiko Ohta ◽  
Shigenori Yamaguchi ◽  
Yoshihiko Ito ◽  
Yasuhisa Shinmoto ◽  
Yoshiyuki Abe
Keyword(s):  
Aqueous Solutions ◽  
Thermal Management ◽  
Nucleate Boiling ◽  
Management Systems ◽  
Low Concentration
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