CAD/CAE method of solving the hydrodynamic problem while developing powerful electronic devices

The article presents examples of the solution of the hydrodynamic problem that arises in the development of powerful electronic devices requiring liquid cooling using the CAD/CAE modeling method. The authors consider poorly documented or undocumented features of such solution based on the use of free software packages — SALOME, OpenFOAM and ParaView for the CAELinux operating system platform.Необхідність вирішення гідродинамічної задачі виникає в тому випадку, коли для забезпечення теплового режиму електронного приладу необхідним є застосування примусового рідинного охолодження, реалізованого у вигляді охолоджувачів тієї чи іншої конструкції. Результатом її рішення є вибір насоса, здатного подолати гідродинамічний опір охолоджувача при заданих значеннях витрати рідини. Вибрати насос не важко, коли відома гідродинамічна характеристика охолоджувача — залежність надлишкового тиску рідини на вході від швидкості рідини, яка протікає через охолоджувач. Тенденція до ускладнення конструкцій охолоджувачів з нетрадиційними течіями виключає використання відомих аналітичних залежностей і вимагає застосування інших методів, наприклад математичного моделювання. Його основні етапи: розробка 3D геометричної моделі охолоджувача; визначення в її межах швидкості і тиску рідини шляхом вирішення системи диференціальних рівнянь нерозривності і Нав'є — Стокса; представлення результатів рішення в вигляді, зручному для аналізу. Для реалізації такого підходу потрібне спеціалізоване програмне забезпечння (ПЗ) типу CAD/CAE. Дорожнеча пропрієтарних CAD/CAE-систем разом з вимогою використання при проектуванні виключно легального ПЗ викликали необхідність вирішення зазначеної задачі за допомогою вільних програмних продуктів, наприклад системи геометричного моделювання SALOME, системи математичного моделювання OpenFOAM і візуалізатора паралельних обчислень ParaView. Серед основних перешкод застосування зазначеного ПЗ — його слабка документованість. Мета даної роботи — показати на практичних прикладах, заснованих на досвіді проектування рідинних охолоджувачів для мікропроцесорів, недокументовані особливості використання SALOME, OpenFOAM і ParaView на платформі операційної системи CAELinux. У роботі на двох прикладах докладно розглянуто методику рішення задачі, що дозволяє успішно застосовувати даний підхід при проектуванні складних реальних конструкцій охолоджувачів електронних приладів.Приведены примеры решения гидродинамической задачи, которая возникает при разработке мощных электронных приборов, требующих жидкостного охлаждения, методом CAD/CAE-моделирования. Рассмотрены не документированные или слабо документированные особенности ее решения на основе использования свободного программного обеспечения SALOME, OpenFOAM и ParaView на платформе операционной системы CAELinux

Quality control for the first large areas of triple-GEM chambers for the CMS endcaps

The CMS Collaboration plans to equip the very forward muon system with triple-GEM detectors that can withstand the environment of the High-Luminosity LHC.This project is at the final stages of R&D and moving to production. A large area of several 100 m 2 are to be instrumented with GEM detectors which will be produced in six different sites around the world. A common construction and quality control procedure is required to ensure the performance of each detector.The quality control steps will include optical inspection,cleaning and baking of all materials and parts used to build the detector,leakage current tests of the GEM foils,high voltage tests,gas leak tests of the chambers and monitoring pressures time,gain calibration to know the optimal operation region of the detector,gain uniformity tests, and studying the efficiency,noise and tracking performance of the detectors in a cosmic stand using scintillator

The replication database: documenting the replicability of psychological science

In psychological science, replicability — repeating a study with a new sample achieving consistent results (Parsons et al., 2022) — is critical for affirming the validity of scientific findings. Despite its importance, replication efforts are few and far between in psychological science with many attempts failing to corroborate past findings. This scarcity, compounded by the difficulty in accessing replication data, jeopardizes the efficient allocation of research resources and impedes scientific advancement. Addressing this crucial gap, we present the Replication Database (https://forrt-replications.shinyapps.io/fred_explorer), a novel platform hosting 1,239 original findings paired with replication findings. The infrastructure of this database allows researchers to submit, access, and engage with replication findings. The database makes replications visible, easily findable via a graphical user interface, and tracks replication rates across various factors, such as publication year or journal. This will facilitate future efforts to evaluate the robustness of psychological research

A Multilab Replication of the Induced-Compliance Paradigm of Cognitive Dissonance

According to cognitive-dissonance theory, performing counterattitudinal behavior produces a state of dissonance that people are motivated to resolve, usually by changing their attitude to be in line with their behavior. One of the most popular experimental paradigms used to produce such attitude change is the induced-compliance paradigm. Despite its popularity, the replication crisis in social psychology and other fields, as well as methodological limitations associated with the paradigm, raise concerns about the robustness of classic studies in this literature. We therefore conducted a multilab constructive replication of the induced-compliance paradigm based on Croyle and Cooper (Experiment 1). In a total of 39 labs from 19 countries and 14 languages, participants (N = 4,898) were assigned to one of three conditions: writing a counterattitudinal essay under high choice, writing a counterattitudinal essay under low choice, or writing a neutral essay under high choice. The primary analyses failed to support the core hypothesis: No significant difference in attitude was observed after writing a counterattitudinal essay under high choice compared with low choice. However, we did observe a significant difference in attitude after writing a counterattitudinal essay compared with writing a neutral essay. Secondary analyses revealed the pattern of results to be robust to data exclusions, lab variability, and attitude assessment. Additional exploratory analyses were conducted to test predictions from cognitive-dissonance theory. Overall, the results call into question whether the induced-compliance paradigm provides robust evidence for cognitive dissonance. © The Author(s) 2024.Open access articleThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Quality control for the first large areas of triple-GEM chambers for the CMS endcaps

The CMS Collaboration plans to equip the very forward muon system with triple-GEM detectors that can withstand the environment of the High-Luminosity LHC. This project is at the final stages of R&D and moving to production. An unprecedented large area of several 100 m2 are to be instrumented with GEM detectors which will be produced in six different sites around the world. A common construction and quality control procedure is required to ensure the performance of each detector. The quality control steps will include optical inspection, cleaning and baking of all materials and parts used to build the detector, leakage current tests of the GEM foils, high voltage tests, gas leak tests of the chambers and monitoring pressure drop vs. time, gain calibration to know the optimal operation region of the detector, gain uniformity tests, and studying the efficiency, noise and tracking performance of the detectors in a cosmic stand using scintillators

Quality control for the first large areas of triple-GEM chambers for the CMS endcaps

International audienceThe CMS Collaboration plans to equip the very forward muon system with triple-GEM detectors that can withstand the environment of the High-Luminosity LHC. This project is at the final stages of R&D and moving to production. An unprecedented large area of several 100 m2 are to be instrumented with GEM detectors which will be produced in six different sites around the world. A common construction and quality control procedure is required to ensure the performance of each detector. The quality control steps will include optical inspection, cleaning and baking of all materials and parts used to build the detector, leakage current tests of the GEM foils, high voltage tests, gas leak tests of the chambers and monitoring pressure drop vs. time, gain calibration to know the optimal operation region of the detector, gain uniformity tests, and studying the efficiency, noise and tracking performance of the detectors in a cosmic stand using scintillators

A novel application of Fiber Bragg Grating (FBG) sensors in MPGD

We present a novel application of Fiber Bragg Grating (FBG) sensors in the construction and characterisation of Micro Pattern Gaseous Detector (MPGD), with particular attention to the realisation of the largest triple (Gas electron Multiplier) GEM chambers so far operated, the GE1/1 chambers of the CMS experiment at LHC. The GE1/1 CMS project consists of 144 GEM chambers of about 0.5 m2 active area each, employing three GEM foils per chamber, to be installed in the forward region of the CMS endcap during the long shutdown of LHC in 2108-2019. The large active area of each GE1/1 chamber consists of GEM foils that are mechanically stretched in order to secure their flatness and the consequent uniform performance of the GE1/1 chamber across its whole active surface. So far FBGs have been used in high energy physics mainly as high precision positioning and re-positioning sensors and as low cost, easy to mount, low space consuming temperature sensors. FBGs are also commonly used for very precise strain measurements in material studies. In this work we present a novel use of FBGs as flatness and mechanical tensioning sensors applied to the wide GEM foils of the GE1/1 chambers. A network of FBG sensors have been used to determine the optimal mechanical tension applied and to characterise the mechanical tension that should be applied to the foils. We discuss the results of the test done on a full-sized GE1/1 final prototype, the studies done to fully characterise the GEM material, how this information was used to define a standard assembly procedure and possible future developments