A Model Predictive Framework for Thermal Management of Aircraft

2015 ◽  
Author(s):  
Timothy O. Deppen ◽  
Joel E. Hey ◽  
Andrew G. Alleyne ◽  
Timothy S. Fisher
Keyword(s):  
Thermal Management ◽  
High Performance ◽  
Heat Dissipation ◽  
Electrical Power ◽  
Electrical Equipment ◽  
Thermal Loads ◽  
Case Scenario ◽  
Worst Case ◽  
Order Of Magnitude ◽  
Transient Thermal

The challenge of managing heat dissipation and enforcing operational constraints on temperature within a high-performance tactical aircraft is considered. For these systems, power density of the electrical equipment and the associated thermal loads are quickly outpacing the means of conventional thermal management systems (TMS) to provide on-demand cooling and in order to prevent thermal run away. The next generation of tactical aircraft is projected to include an order of magnitude greater thermal and electrical power magnitudes, and the time scale over which thermal loads will change is expected to shrink. To meet this rapidly evolving challenge, designing a TMS for the “worst case” scenario based on a steady-state thermal analysis will be infeasible. Rather, a holistic systems perspective is needed with new control methodologies that capture and even exploit the transient thermal behavior. To this end, a model predictive control strategy is presented that utilizes preview of upcoming loads and disturbances to prevent violation of temperature constraints. A simulation case study demonstrates that the predictive thermal controller can dramatically reduce constraint violations while reducing the work required by the TMS when compared to a cascaded PI feedback controller.

MX2 Processor Module: Twice the Processors in Half the Volume

2005 ◽  
Author(s):  
Christian Belady ◽  
Gary Williams ◽  
Shaun Harris
Keyword(s):  
High Performance ◽  
Power Converter ◽  
Case Scenario ◽  
Worst Case ◽  
Physical Volume ◽  
Performance Per Watt ◽  
Innovative Solution ◽  
Order Of Magnitude ◽  
Processor Module ◽  
Better Than

Computer manufacturer’s are constantly trying to tweek more performance out of their existing products by using the highest performing processors. Typically, manufacturers upgrade the platforms by simply replacing the old processor with the latest speed processor. Like other manufacturers, HP generally follows this practice with the exception ot HP’s innovative mx2 module. This unique module used two Itanium-2 “Madison” processors packaged in the same physical volume as a single Itanium-2 processor. In addition, the module plugs into a standard Itanium-2 motherboard socket and requires no additional power capacity. As a result, the development team was able get 50% more performance [1] from a socket without increasing power by actively managing the power to the two processors. Thus, the performance per watt was substantially improved. This paper will provide an overview of some of the key packaging and power innovations that made the processor module a reality such as: 1) mezzanine power for space savings. The standard Itanium 2 processor has a power converter adjacent to the processor. HP engineers chose to put power on top of the processor which provided more room but made cooling the processors a challenge. 2) high performance mechnical gap filler. One of the biggest issues in the module was to develop a thermal gap filler that absorbed 0.060” of tolerance between the two processors. The thermal resistance of this technology was an order of magnitude better than anything commercially available in the industry. 3) Power Aware Architecture. This newly developed power mangement technology actively controls power to the processors. When system (thermal and power) extremes were exceeded by worst case abnormal code, the performance was throttled down until the worst case scenario had past. The combination of these advancements has delivered an innovative solution for a highly challenging design problem. This module is now shipping as the mx2 processor module in HP’s Integrity Servers and has been viewed as an engineering marvel by HP executives.

Stress Analyses of Flip TAB Interconnects in Multi-Chip Module Assembly

1991 ◽  
Vol 113 (3) ◽  
pp. 226-232 ◽  
Author(s):  
Ben Nagaraj ◽  
Mali Mahalingam
Keyword(s):  
High Performance ◽  
Heat Dissipation ◽  
Mechanical Load ◽  
Design Guidelines ◽  
Physical Contact ◽  
Thermal Loads ◽  
Force Components ◽  
Effect Of The Support ◽  
Supporting Element ◽  
Generic Design

Flip Tape Automated Bond (FTAB) interconnect is one of the leading candidates for device to substrate interconnection in a high performance Multi-Chip Module (MCM). The TAB interconnect becomes a structural member in the MCM assembly, bearing both “mechanical” and “thermal” loads. Further, to accomplish high thermal performance in the assembly, physical contact to the device may be made under substantial contact pressures. The device may be supported by elastic structures to redistribute the interconnect forces. Finite Element Methods (FEM) are used to analyze the structural behavior of TAB interconnects under (i) the applied mechanical load to the device and (ii) the thermal loads due to the heat dissipation in the device. Variation of the force components on the TAB interconnects and the maximum failure criterion based on the stresses in the interconnects are reported. Effect of the support area and the modulus of the supporting element on the interconnects are discussed. Generic design guidelines are presented for flip TAB interconnect based MCM assembly.

scholarly journals Recent Advances in Design and Preparation of Polymer-Based Thermal Management Material

Polymers ◽  
2021 ◽  
Vol 13 (16) ◽  
pp. 2797 ◽  
Author(s):  
Hongli Zhang ◽  
Tiezhu Shi ◽  
Aijie Ma
Keyword(s):  
Thermal Management ◽  
High Performance ◽  
Heat Dissipation ◽  
Electronic Devices ◽  
High Heat ◽  
Consumer Electronics ◽  
Recent Advances ◽  
Processing Strategies ◽  
Innovative Material ◽  
Processing Properties

The boosting of consumer electronics and 5G technology cause the continuous increment of the power density of electronic devices and lead to inevitable overheating problems, which reduces the operation efficiency and shortens the service life of electronic devices. Therefore, it is the primary task and a prerequisite to explore innovative material for meeting the requirement of high heat dissipation performance. In comparison with traditional thermal management material (e.g., ceramics and metals), the polymer-based thermal management material exhibit excellent mechanical, electrical insulation, chemical resistance and processing properties, and therefore is considered to be the most promising candidate to solve the heat dissipation problem. In this review, we summarized the recent advances of two typical polymer-based thermal management material including thermal-conduction thermal management material and thermal-storage thermal management material. Furtherly, the structural design, processing strategies and typical applications for two polymer-based thermal management materials were discussed. Finally, we proposed the challenges and prospects of the polymer-based thermal management material. This work presents new perspectives to develop advanced processing approaches and construction high-performance polymer-based thermal management material.

scholarly journals Occurrence and Exposure Assessment of Mycotoxins in Ready-to-Eat Tree Nut Products through Ultra-High Performance Liquid Chromatography Coupled with High Resolution Q-Orbitrap Mass Spectrometry

Metabolites ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 344
Author(s):  
Alfonso Narváez ◽  
Yelko Rodríguez-Carrasco ◽  
Luigi Castaldo ◽  
Luana Izzo ◽  
Giulia Graziani ◽  
...  
Keyword(s):  
High Performance ◽  
Daily Intake ◽  
Monomethyl Ether ◽  
Health State ◽  
Fungal Contamination ◽  
Alternariol Monomethyl Ether ◽  
Case Scenario ◽  
Worst Case ◽  
Tree Nut ◽  
Orbitrap Mass Spectrometry

Tree nuts have become popular snacks due to their attributed benefits in the health state. Nevertheless, their susceptibility to fungal contamination lead to the occurrence of potentially dangerous mycotoxins. Hence, the aim of this work was to evaluate the presence of mycotoxins in ready-to-eat almonds, walnuts, and pistachios from Italian markets. The most relevant mycotoxin found in almonds was α-zearalanol in 18% of samples (n = 17) ranging from 3.70 to 4.54 µg/kg. Walnut samples showed frequent contamination with alternariol, present in 53% of samples (n = 22) at levels from 0.29 to 1.65 µg/kg. Pistachios (n = 15) were the most contaminated commodity, with β-zearalenol as the most prevalent toxin present in 59% of samples ranging from 0.96 to 8.60 µg/kg. In the worst-case scenario, the exposure to zearalenone-derived forms accounted for 15.6% of the tolerable daily intake, whereas it meant 12.4% and 21.2% of the threshold of toxicological concern for alternariol and alternariol monomethyl-ether, respectively. The results highlighted the extensive presence of Alternaria toxins and zearalenone-derived forms, scarcely studied in ready-to-eat tree nut products, highlighting the necessity to include these mycotoxins in analytical methods to perform more realistic risk assessments.

scholarly journals Safety issues in solid fuel heating installed in closed systems without heat dissipation devices

2020 ◽  
Vol 24 (2 Part B) ◽  
pp. 1369-1379
Author(s):  
Borivoj Stepanov ◽  
Momcilo Spasojevic ◽  
Zeljko Vlaovic ◽  
Kalman Babkovic ◽  
Djordjije Doder ◽  
...  
Keyword(s):  
Solid Fuel ◽  
Heat Dissipation ◽  
Open Systems ◽  
Safety Valve ◽  
Heating System ◽  
Case Scenario ◽  
Worst Case ◽  
Safety Issues ◽  
Closed Systems ◽  
Boiler Design

The objective of this paper is to raise awareness of the risk of boiling liquid expanding vapor explosions (steam explosions) in heating systems in Serbia caused by a combination of the following factors: solid fuel burning, older boiler design, closed systems, and non-installation of heat dissipation devices. The practice is in accordance with neither Standard SRPS EN 303-5:2012 nor subject literature, which both demand that this type of heating be installed in open systems. Explosions do occur; there was one in 2014 in Futog, Serbia, with fatal consequences. The main protection element, safety valve, is designed for temperatures up to 110?C. Its operation above 110?C is unknown. The experiment physically simulated the worst case scenario, where there is no circulation in the heating system. It used a 90 L water-filled vessel with six 3 kW electric heaters installed and safety valves attached. This paper presents the first results for the case where the set pressure of the safety valve was 1.5 bar and one heater of 3 kW was in operation. The results showed that the safety valve did not prevent boiling. The recorded pressure peaks were at 2.2 bar and the lows were at 0.8 bar, so its operation intensified boiling. Therefore, the system cannot be considered safe even with a brand new safety valve and at low overheating rates. Better air removal in the system is to be solved in future experiments. Tests will be done with different safety valves and overheating rates.

scholarly journals Occurrence and Risk Assessment of Mycotoxins through Polish Beer Consumption

Toxins ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 254 ◽  
Author(s):  
Jan Grajewski ◽  
Robert Kosicki ◽  
Magdalena Twarużek ◽  
Anna Błajet-Kosicka
Keyword(s):  
Ochratoxin A ◽  
High Performance ◽  
Daily Intake ◽  
Maximum Level ◽  
Case Scenario ◽  
Limit Of Quantification ◽  
Worst Case ◽  
Beer Consumption ◽  
Food Consumption Data ◽  
The Mean

Poland is one of Europe’s leading producers and exporters of beer. The study, herein, describes the measurement of ochratoxin A, deoxynivalenol, nivalenol, T-2 toxin, HT-2 toxin, diacetoxyscirpenol, and zearalenone levels in 69 Polish beers. Analytical methodologies based on high performance liquid chromatography (HPLC) with tandem mass spectrometry (MS/MS) and fluorescence detection were developed, validated, and used to perform the above determinations. The most prevalent mycotoxins were deoxynivalenol (96%), ochratoxin A (93%), and HT-2 toxin (74%), respectively. Three quarters of the samples contained at least three analytes. The mean ochratoxin A concentration was 0.057 (SD 0.065) ng/mL, and in four beer samples its level exceeded 0.2 ng/mL, a value postulated in the literature to be the maximum limit. Deoxynivalenol was found at a maximum level of 56.2 ng/mL, and its mean concentration was 17.1 (SD 9.0) ng/mL. An evaluation of the estimated daily intake (EDI) of mycotoxins from beer in different European populations was made using food-consumption data prepared by WHO. Based on the mean ochratoxin A concentration in beers, the EDI represented 0.8–1.1% of the tolerable daily intake (TDI), while in a worst-case scenario (maximum concentration) it reached 5.0–7.5% of TDI. For deoxynivalenol, the EDI was in the range of 4.1–6.0% of TDI, whereas, based on maximum values, it reached the level of 14–21% of TDI. There were no significant differences between “scenarios” in the HT-2 case (mean—5.0–7.5% of TDI; maximum—6.5–9.7% of TDI) due to the fact that its concentration was near the limit of quantification (LOQ) value taken for calculation. The significance of these results are discussed, herein.

Benchmarking Study on the Thermal Management Landscape for 3D ICs: From Back-Side to Volumetric Heat Removal

2015 ◽  
Author(s):  
Thomas Brunschwiler ◽  
Arvind Sridhar ◽  
Chin Lee Ong ◽  
Gerd Schlottig
Keyword(s):  
Thermal Management ◽  
Power Dissipation ◽  
High Performance ◽  
Heat Dissipation ◽  
Hybrid Approach ◽  
Heat Removal ◽  
Back Side ◽  
Cooling Channels ◽  
Fluid Delivery ◽  
Single Side

An overview of the thermal management landscape with focus on heat dissipation from 3D chip stacks is provided in this study. Evolutionary and revolutionary topologies, such as single-side, dual-side and, finally, volumetric heat removal, are benchmarked with respect to a high-performance three-tier chip stack with an aggregate power dissipation of 672 W. The thermal budget of 50 K can be maintained by three topologies, namely, 1) dual-side cooling, implemented by a thermally active interposer, 2) interlayer cooling with 4-port fluid delivery and drainage at 100 kPa pressure drop, and 3) a hybrid approach combining interlayer with embedded back-side cooling. Of all the heat-removal concepts, interlayer cooling is the only approach that scales with the number of dies in the chip stack and hence, enables extreme 3D integration. However, the required size of the microchannels competes with the requirement of low TSV heights and pitches. A scaling study was performed to derive the TSV pitch that is compatible with cooling channels to dissipate 150 W/cm2 per tier. An active IC area of 4 cm2 was considered, which had to be implemented on the varying tier count in the stack. A cuboid form factor of 2 mm × 4 mm × 2.55 mm results from a die count of 50. The resulting microchannels of 2 mm length allow small hydraulic diameters and thus a very high TSV density of 1837 1/mm2. The accumulated heat flux and the volumetric power dissipation are as high as 7.5 kW/cm2 and 29kW/cm3, respectively.

A System to Package Perspective on Transient Thermal Management of Electronics

2020 ◽  
Vol 142 (4) ◽  
Author(s):  
H. Peter de Bock ◽  
David Huitink ◽  
Patrick Shamberger ◽  
James Spencer Lundh ◽  
Sukwon Choi ◽  
...  
Keyword(s):  
Steady State ◽  
Thermal Management ◽  
Thermal Design ◽  
System Level ◽  
Control Mechanisms ◽  
Thermal Loads ◽  
Chip Surface ◽  
Wide Range ◽  
Transient Thermal ◽  
The Way

Abstract There are many applications throughout the military and commercial industries whose thermal profiles are dominated by intermittent and/or periodic pulsed thermal loads. Typical thermal solutions for transient applications focus on providing sufficient continuous cooling to address the peak thermal loads as if operating under steady-state conditions. Such a conservative approach guarantees satisfying the thermal challenge but can result in significant cooling overdesign, thus increasing the size, weight, and cost of the system. Confluent trends of increasing system complexity, component miniaturization, and increasing power density demands are further exacerbating the divergence of the optimal transient and steady-state solutions. Therefore, there needs to be a fundamental shift in the way thermal and packaging engineers approach design to focus on time domain heat transfer design and solutions. Due to the application-dependent nature of transient thermal solutions, it is essential to use a codesign approach such that the thermal and packaging engineers collaborate during the design phase with application and/or electronics engineers to ensure the solution meets the requirements. This paper will provide an overview of the types of transients to consider—from the transients that occur during switching at the chip surface all the way to the system-level transients which transfer heat to air. The paper will cover numerous ways of managing transient heat including phase change materials (PCMs), heat exchangers, advanced controls, and capacitance-based packaging. Moreover, synergies exist between approaches to include application of PCMs to increase thermal capacitance or active control mechanisms that are adapted and optimized for the time constants and needs of the specific application. It is the intent of this transient thermal management review to describe a wide range of areas in which transient thermal management for electronics is a factor of significance and to illustrate which specific implementations of transient thermal solutions are being explored for each area. The paper focuses on the needs and benefits of fundamentally shifting away from a steady-state thermal design mentality to one focused on transient thermal design through application-specific, codesigned approaches.

Structural Assessment of Reactor Pressure Vessel Under Core Melting Conditions

2013 ◽  
Author(s):  
Seung-Hyun Kim ◽  
Yoon-Suk Chang
Keyword(s):  
Pressure Vessel ◽  
Power Plants ◽  
Reactor Pressure Vessel ◽  
Severe Accident ◽  
Sensitivity Analyses ◽  
Thermal Loads ◽  
Case Scenario ◽  
Worst Case ◽  
Reactor Pressure ◽  
Melting Conditions

The worst case scenario including melt-down of reactor core components has been recognized as one of the safety issues. Without any counter measure, this may lead to penetration of RPV (Reactor Pressure Vessel) due to significant thermal loads caused by the relocation of molten core debris into the lower plenum. The present paper shows applicability of ERVC (External Reactor Vessel Cooling), aimed at limiting radiological releases by adopting the in-vessel retention concept, under core melting conditions. Systematic numerical analyses were carried out by taking into account diverse melting progress mechanisms, properties and amounts of molten debris, and damage models. Consequences of the thermal loads under assumed core melting conditions, such as the critical locations and time to reach penetration of the RPV lower plenum, were compared as a part of sensitivity analyses. Also, influences of each parameter were examined and technical findings from the assessment were discussed to demonstrate effectiveness of the ERVC for severe accident mitigation features of new power plants.

scholarly journals Analysis of Voltage Rise Phenomena in Electrical Power Network With High Concentration of Renewable Distributed Generations

2022 ◽  
Author(s):  
AYODEJI AKINYEMI ◽  
Kabeya Musasa ◽  
Innocent Davidson
Keyword(s):  
Power System ◽  
Control Strategy ◽  
Power Flow ◽  
Electrical Power ◽  
Test System ◽  
Distribution Grid ◽  
High Concentration ◽  
Case Scenario ◽  
Worst Case ◽  
Voltage Rise

Abstract The increasing penetration levels of Renewable Distributed Generation (RDG) into power system have proven to bring both positive and negative impacts. The occurrence of under voltage at the far end of a conventional Distribution Network (DN) may not raise concern anymore with RDGs integration into the power system. However, a high penetration of RDG into power system may cause problems such as voltage rise or over-voltage and reverse power flows at the Point of Common Coupling (PCC) between RDG and DN. This research paper presents the voltage rise and reverse power flow effects in power system with high concentration of RDG. The analysis is conducted on a sample DN, i.e., IEEE 13-bus test system, with RDG by considering the most critical scenario such as low power demand and peak power injection to DN from RDG. The Simulations are carried out using MATLAB/Simulink software, a mathematical model of a distribution grid, integrating RDG is developed for studying the effects of voltage rise and bidirectional flow of power. Furthermore, a control strategy is proposed to be installed at PCC of the DN to control/or mitigate the voltage rise effects and to limit the reverse power flow when operating in a worst critical scenario of minimum load and maximum generation from RDG. The proposed control strategy also mitigates the voltage-current harmonic signals, improve the power factor, and voltage stability at PCC. Finally, recommendations are provided for the utility and independent power producer to counteract the effects of voltage rise at PCC. The study demonstrated that, PCC voltage can be sustained with a high concentration of RDG during a worst-case scenario without a reverse power flow and voltage rise beyond grid code limits.

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