ЭКСПЕРИМЕНТАЛЬНОЕ ОПРЕДЕЛЕНИЕ ИНТЕНСИВНОСТИ ТЕПЛООБМЕНА ПРИ ВЫНУЖДЕННОЙ КОНВЕКЦИИ ВОЗДУХА ВО ВНУТРЕННИХ КАНАЛАХ ПЛОСКИХ ТРУБ

The paper describes an installation and methods of experimental studies concerning heat transfer processes under forced air convection in internal channels of the flat pipes, which allow to take measurements of heat transfer intensity. The paper presents measurements of heat transfer intensity in respect of pipes with separate ribs of small height and pipes with channels, communicating with the help of round holes.Описаны установка и методика экспериментальных исследований процессов теплоотдачи при вынужденной конвекции воздуха во внутренних каналах плоских труб, которые позволяют проводить измерения интенсивности теплообмена. Приведены результаты измерений интенсивности теплообмена для труб с отдельными ребрами малой высоты и труб с каналами, сообщающихся при помощи круглых отверстий

The Optical Instrumentation of the ATLAS Tile Calorimeter

The purpose of this Note is to describe the optical assembly procedure called here Optical Instrumentation and the quality tests conducted on the assembled units. Altogether, 65 Barrel (or LB) modules were constructed - including one spare - together with 129 Extended Barrel (EB) modules (including one spare). The LB modules were mechanically assembled at JINR (Dubna, Russia) and transported to CERN, where the optical instrumentation was performed with personnel contributed by several Institutes. The modules composing one of the two Extended Barrels (known as EBA) were mechanically assembled in the USA, and instrumented in two US locations (ANL, U. of Michigan), while the modules of the other Extended barrel (EBC) were assembled in Spain and instrumented at IFAE (Barcelona). Each of the EB modules includes a subassembly known as ITC that contributes to the hermeticity of the calorimeter; all ITCs were assembled at UTA (Texas), and mounted onto the module mechanical structures at the EB mechanical assembly locations.The Tile Calorimeter, covering the central region of the ATLAS experiment up to pseudorapidities of ±1.7, is a sampling device built with scintillating tiles that alternate with iron plates. The light is collected in wave-length shifting (WLS) fibers and is read out with photomultipliers. In the characteristic geometry of this calorimeter the tiles lie in planes perpendicular to the beams, resulting in a very simple and modular mechanical and optical layout. This paper focuses on the procedures applied in the optical instrumentation of the calorimeter, which involved the assembly of about 460,000 scintillator tiles and 550,000 WLS fibers. The outcome is a hadronic calorimeter that meets the ATLAS performance requirements, as shown in this paper

The Production and Qualification of Scintillator Tiles for the ATLAS Hadronic Calorimeter

The production of the scintillator tiles for the ATLAS Tile Calorimeter is presented. In addition to the manufacture and production, the properties of the tiles will be presented including light yield, uniformity and stability

Обобщение результатов исследований теплообмена между потоком воздуха и оребренной поверхностью, полученной при подрезании ребер со смещением оси

The given paper contains an analysis and presents a generalization of experimental results pertaining to heat exchange between an air flow and a surface of a flat pipe when its finning is made with various values of displacement of a tool rotation axis relative to a symmetry axis of a blank.Criterion dependences obtained as result of experimental data generalization provide the possibility to use them for calculation of external heat exchange intensity and losses of pressure in heat exchangers made of aluminum flat fined tubes.Проведен анализ и представлено обобщение результатов экспериментальных исследований теплообмена между потоком воздуха и поверхностью плоской трубы, оребрение которой было выполнено с различными величинами смещения оси вращения инструмента относительно оси симметрии заготовки.Полученные в результате обобщения экспериментальных данных критериальные зависимости дают возможность использовать их при проведении расчетов интенсивности внешнего теплообмена и потерь давления в теплообменниках, изготовленных из плоских оребренных алюминиевых труб

EXPERIMENTAL DETERMINATION OF HEAT TRANSFER INTENSITY UNDER FORCED AIR CONVECTION IN INTERNAL CHANNELS OF FLAT PIPES

The paper describes an installation and methods of experimental studies concerning heat transfer processes under forced air convection in internal channels of the flat pipes, which allow to take measurements of heat transfer intensity. The paper presents measurements of heat transfer intensity in respect of pipes with separate ribs of small height and pipes with channels, communicating with the help of round holes

Experimental evaluation of the effect of cryogenic treatment of brake discs of the vehicle on the performance characteristics

Abstract The article presents the conclusions and prerequisites of the experimental evaluation of friction pairs in the aspect of fading. The most part of kinetic energy of the vehicle with ABS is extinguished at the expense of friction work in the brake mechanism. Thus, the overheating of the brake mechanism, namely its pair of friction is peculiar to vehicles not equipped with ABS (for example, ATV) and leads to the phenomenon of critical fading, accompanied by a sharp decrease in braking torque. The reduction of the influence of this phenomenon is a very difficult task in terms of both taking into account the cost of the braking mechanism and its minimal complication. The authors suggest the use of cryogenic processing of brake disks to reduce the impact of thermal loading on the emergence of fading.</jats:p

Generalization of Investigation Results Pertaining to Heat Exchange between Air Flow and Finned Surface Obtained at Fin Cutting with Axis Displacement

The given paper contains an analysis and presents a generalization of experimental results pertaining to heat exchange between an air flow and a surface of a flat pipe when its finning is made with various values of displacement of a tool rotation axis relative to a symmetry axis of a blank.Criterion dependences obtained as result of experimental data generalization provide the possibility to use them for calculation of external heat exchange intensity and losses of pressure in heat exchangers made of aluminum flat fined tubes