Influence of the Coulomb Force on Spray Cooling

In this study, satellite formation flying guidance in the presence of under actuation using inter-vehicle Coulomb force is investigated. The Coulomb forces are used to stabilize the formation flying mission. For this purpose, the charge of satellites is determined to create appropriate attraction and repulsion and also, to maintain the distance between satellites. Static Coulomb formation of satellites equations including three satellites in triangular form was developed. Furthermore, the charge value of the Coulomb propulsion system required for such formation was obtained. Considering Under actuation of one of the formation satellites, the fault-tolerance approach is proposed for achieving mission goals. Following this approach, in the first step fault-tolerant guidance law is designed. Accordingly, the obtained results show stationary formation. In the next step, tomaintain the formation shape and dimension, a fault-tolerant control law is designed.

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Spray Cooling for Time Resolved Emission Measurements of ICs

ISTFA 2004: Conference Proceedings from the 30th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2004p0018 ◽

2004 ◽

Author(s):

Rama R. Goruganthu ◽

David Bethke ◽

Shawn McBride ◽

Tom Crawford ◽

Jonathan Frank ◽

...

Keyword(s):

Heat Flux ◽

Thermal Performance ◽

Flip Chip ◽

Cooling System ◽

Spray Cooling ◽

Junction Temperature ◽

Maximum Temperature ◽

Uniform Heat Flux ◽

High Heat Flux ◽

Time Resolved

Abstract Spray cooling is implemented on an engineering tool for Time Resolved Emission measurements using a silicon solid immersion lens to achieve high spatial resolution and for probing high heat flux devices. Thermal performance is characterized using a thermal test vehicle consisting of a 4x3 array of cells each with a heater element and a thermal diode to monitor the temperature within the cell. The flip-chip packaged TTV is operated to achieve uniform heat flux across the die. The temperature distribution across the die is measured on the 4x3 grid of the die for various heat loads up to 180 W with corresponding heat flux of 204 W/cm2. Using water as coolant the maximum temperature differential across the die was about 30 °C while keeping the maximum junction temperature below 95 °C and at a heat flux of 200 W/cm2. Details of the thermal performance of spray cooling system as a function of flow rate, coolant

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Optimization of operational parameters for a photovoltaic panel cooled by spray cooling

Engineering Science and Technology an International Journal ◽

10.1016/j.jestch.2021.04.002 ◽

2021 ◽

Author(s):

Faruk Yesildal ◽

Ahmet Numan Ozakin ◽

Kenan Yakut

Keyword(s):

Spray Cooling ◽

Operational Parameters ◽

Photovoltaic Panel

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Reduction of CO2 Emissions in Steelmaking by Means of Utilization of Steel Plant Waste Heat to Stabilize Seasonal Cooling Water Temperature

Sustainability ◽

10.3390/su13115957 ◽

2021 ◽

Vol 13 (11) ◽

pp. 5957

Author(s):

Tomas Mauder ◽

Michal Brezina

Keyword(s):

Continuous Casting ◽

Water Temperature ◽

Co2 Emissions ◽

Waste Heat ◽

Cooling Water ◽

Main Idea ◽

Casting Process ◽

Spray Cooling ◽

Steel Plant ◽

Cooling Water Temperature

Production of overall CO2 emissions has exhibited a significant reduction in almost every industry in the last decades. The steelmaking industry is still one of the most significant producers of CO2 emissions worldwide. The processes and facilities used at steel plants, such as the blast furnace and the electric arc furnace, generate a large amount of waste heat, which can be recovered and meaningfully used. Another way to reduce CO2 emissions is to reduce the number of low-quality steel products which, due to poor final quality, need to be scrapped. Steel product quality is strongly dependent on the continuous casting process where the molten steel is converted into solid semifinished products such as slabs, blooms, or billets. It was observed that the crack formation can be affected by the water cooling temperature used for spray cooling which varies during the year. Therefore, a proper determination of the cooling water temperature can prevent the occurrence of steel defects. The main idea is based on the utilization of the waste heat inside the steel plant for preheating the cooling water used for spray cooling in the Continuous Casting (CC) process in terms of water temperature stabilization. This approach can improve the quality of steel and contribute to the reduction of greenhouse gas emissions. The results show that, in the case of billet casting, a reduction in the cooling water consumption can be also reached. The presented tools for achieving these goals are based on laboratory experiments and on advanced numerical simulations of the casting process.

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