Full Scale Proton Beam Impact Testing of new CERN Collimators and Validation of a Numerical Approach for Future Operation

New collimators are being produced at CERN in the framework of a large particle accelerator upgrade project to protect beam lines against stray particles. Their movable jaws hold low density absorbers with tight geometric requirements, while being able to withstand direct proton beam impacts. Such events induce considerable thermo-mechanical loads, leading to complex structural responses, which make the numerical analysis challenging. Hence, an experiment has been developed to validate the jaw design under representative conditions and to acquire online results to enhance the numerical models. Two jaws have been impacted by high-intensity proton beams in a dedicated facility at CERN and have recreated the worst possible scenario in future operation. The analysis of online results coupled to post-irradiation examinations have demonstrated that the jaw response remains in the elastic domain. However, they have also highlighted how sensitive the jaw geometry is to its mounting support inside the collimator. Proton beam impacts, as well as handling activities, may alter the jaw flatness tolerance value by $\pm$ 70 ${\mu}$m, whereas the flatness tolerance requirement is 200 ${\mu}$m. In spite of having validated the jaw design for this application, the study points out numerical limitations caused by the difficulties in describing complex geometries and boundary conditions with such unprecedented requirements.Comment: 22 pages, 17 figures, Prepared for submission to JINS

Lightweight energy absorbing structures for crashworthy design

PhD ThesisThe application of lightweight composite materials into the rail industry requires a stepwise approach to ensure rail vehicle designs can make optimal use of the inherent properties of each material. Traditionally, materials such as steel and aluminium have been used in railway rolling stock to achieve the energy absorption and structural resistance demanded by European rail standards. Adopting composite materials in primary structural roles requires an innovative design approach which makes the best use of the available space within the rolling stock design such that impact energies and loads are accommodated in a managed and predictable manner. This thesis describes the innovative design of a rail driver’s cab to meet crashworthiness and structural requirements using lightweight, cost-effective composite materials. This takes the application of composite materials in the rail industry beyond the current state-of-the-art and delivers design solutions which are readily applicable across rolling stock categories. An overview of crashworthiness with respect to the rail industry is presented, suitable composite materials for incorporation into rolling stock designs are identified and a methodology to reconfigure and enhance the space available within rail vehicles to meet energy absorption requirements is provided. To realise the application of composite materials, this body of work describes the pioneering application of aluminium honeycomb to deliver unique solutions for rail vehicle energy absorbers, as well as detailing the use of lightweight composite materials to react the structural loads into the cab and carbody. To prove the capability of the design it is supported by finite element analysis and the construction of a full-scale prototype cab which culminated in the successful filing of two patents to protect the intellectual property of the resulting design.The European Commission whose Framework 6 funded project “De-Light” (Contract Number 031483) forms the basis of this work

Application of optimization techniques to vehicle design: A review

The work that has been done in the last decade or so in the application of optimization techniques to vehicle design is discussed. Much of the work reviewed deals with the design of body or suspension (chassis) components for reduced weight. Also reviewed are studies dealing with system optimization problems for improved functional performance, such as ride or handling. In reviewing the work on the use of optimization techniques, one notes the transition from the rare mention of the methods in the 70's to an increased effort in the early 80's. Efficient and convenient optimization and analysis tools still need to be developed so that they can be regularly applied in the early design stage of the vehicle development cycle to be most effective. Based on the reported applications, an attempt is made to assess the potential for automotive application of optimization techniques. The major issue involved remains the creation of quantifiable means of analysis to be used in vehicle design. The conventional process of vehicle design still contains much experience-based input because it has not yet proven possible to quantify all important constraints. This restraint on the part of the analysis will continue to be a major limiting factor in application of optimization to vehicle design

Design and Characterization for Regenerative Shock Absorbers

L'abstract è presente nell'allegato / the abstract is in the attachmen

Summary of the CERN Workshop on Materials for Collimators and Beam Absorbers

The main focus of the workshop was on collimators and beam absorbers for (mainly) High Energy Hadron Accelerators, with the energy stored in the beams far above damage limit. The objective was to better understand the technological limits imposed by mechanisms related to beam impact on materials. The idea to organise this workshop came up during the High Intensity High Brightness Hadron Beams, ICFA-HB2006 in Japan [1]. The workshop was organised 3-5 September 2007 at CERN, with about 60 participants, including 20 from outside CERN. About 30 presentations were given [2]. The event was driven by the LHC challenge, with more than 360 MJoule stored in each proton beam. The entire beam or its fraction will interact with LHC collimators and beam absorbers, and with the LHC beam dump blocks. Collimators and beam absorbers are also of the interest for other labs and accelerators: - CERN: for the CNGS target, for SPS beam absorbers (extraction protection) and collimators for protecting the transfer line between SPS and LHC - GSI: SIS18 and SIS 100/200, Super-FRS target, HED experiments, Antiproton target, etc. - Fermilab: Tevatron and Main Injector collimation systems; neutrino production targets (MINOS, SNuMI, NOVA); antiproton production targets; pion production targets and beam absorbers for neutrino factories and muon colliders - ILC: positron production targets, beam absorbers and collimators for a beam delivery system

APPLICATION OF MODELING AND SIMULATION IN A MANUFACTURING SYSTEM

The aim ofthis project is to develop a simulation model of an air conditioners manufacturing system with a discrete event simulation tool. The model would be utilized as a decision support system for the investigation of improving the process by implementing several options like cost cutting and simplifying operation. This report discusses steps in the development of a simulation model for a manufacturing system using the DES tool, ARENA. A modeling procedure for the development of manufacturing simulation model is presented. The current manufacturing system model is developed to ascertain its limitations and problems to achievethe production target. The steps include data gathering, model building, verification and validation. Several experiments were conducted to recognize parameters useful in the interpretation of the simulation data like the warm up period, run length and number of repetition. The results show that the manufacturing system was improved by 40% by speeding up parts delivery to the system, whilst the waiting time andqueue at each station can be improved by proper line balancing. The findings demonstrates the ability if the approach to provide potential solution to the decision maker

The 25 kWe solar thermal Stirling hydraulic engine system: Conceptual design

The conceptual design and analysis of a solar thermal free-piston Stirling hydraulic engine system designed to deliver 25 kWe when coupled to a 11 meter test bed concentrator is documented. A manufacturing cost assessment for 10,000 units per year was made. The design meets all program objectives including a 60,000 hr design life, dynamic balancing, fully automated control, more than 33.3 percent overall system efficiency, properly conditioned power, maximum utilization of annualized insolation, and projected production costs. The system incorporates a simple, rugged, reliable pool boiler reflux heat pipe to transfer heat from the solar receiver to the Stirling engine. The free-piston engine produces high pressure hydraulic flow which powers a commercial hydraulic motor that, in turn, drives a commercial rotary induction generator. The Stirling hydraulic engine uses hermetic bellows seals to separate helium working gas from hydraulic fluid which provides hydrodynamic lubrication to all moving parts. Maximum utilization of highly refined, field proven commercial components for electric power generation minimizes development cost and risk

Design and Installation Challenges of the Neutral Beam Absorbers for the Large Hadron Collider at CERN

El CERN (Consejo Europeo de Investigación Nuclear) está construyendo su nuevo acelerador de partículas en la frontera franco-suiza. Actualmente en la fase de instalación, El Large Hadron Collider (LHC), con 26,7 kilómetros de longitud a 100 metros bajo tierra, será el mayor y más potente acelerador de partículas jamás construido. A su llegada al CERN, cada uno de casi 2000 imanes superconductores que formarán parte del acelerador debe ser verificado, ensamblado y transportado hasta su punto final de instalación. Una estricta metodología se ha implementado para cumplir los objetivos del Planning General de la Instalación. Sin embargo, ninguna metodología concreta ha sido establecida para la instalación de los componentes más particulares del acelerador. Los Neutral Beam Absorbers son cuatro elementos cuya función principal es absorber el flujo de partículas de alta energía procedentes de los dos principales puntos de colisión del acelerador para proteger los imanes superconductores más próximos a las colisiones. Este proyecto tiene como objetivo definir las necesidades y las soluciones que aseguren la instalación de los 4 Neutral Beam Abosrbers en el acelerador de acuerdo con las especificaciones técnicas definidas y a tiempo con el planning general del LHC. En orden cronológico, este proyecto detalla las instrucciones de manutención, diseño de utillaje y conjunto de actividades que deben respetarse incluyendo: • Estudio de peso y estabilidad frente a seísmos. • Análisis estructural para la correcta manipulación de los frágiles tubos de vacío de cada uno de los Neutral Beam Absorbers. • Dimensionado del sistema de fijación y diseño del utillaje que permita el tratamiento de los tubos de vacío. • Especificación técnica de las necesidades y actividades logísticas que permitan el descenso de los 4 Neutral Beam Absorbers y su transporte por el interior del túnel hasta su punto final de instalación. La metodología establecida en este proyecto ha sido finalizada y aprobada por el CERN, encontrándose en estos momentos (mayo 2005) en la fase de tratamiento de los tubos de vacío y habiendo culminado con éxito las fases precedentes. Asimismo, cada una de las actividades descritas en este proyecto se está desarrollando cumpliendo escrupulosamente con el Planning General de Instalación