Drilling is a standard process for producing holes in metal materials. With an increased hole depth the demands increase on both machine and tool. Deep hole drilling is a complex process which ischaracterized by a high metal removal rate and hole accuracy. A hole deeper than ten times the diameter can be considered a deep hole which requires a specialized drilling technique. During adeep hole drilling process, the forces generated on the deep hole drill give a rise to a resultant radial force. The resultant radial force pushes the drill in a radial direction during a drilling operation. The radial force direction is of crucial importance in regard of tool guidance, stability and hole size accuracy. This force affects tool performance, reduces tool life and has an impact on the bore surface. Due to the complex nature of deep hole drilling, Sandvik Coromant wishes to get a better understanding of how their current deep hole drilling tools are balanced. The purpose of this study is to conduct a survey of a number of drills of Sandvik Coromant deep hole drill assortment. The main aim of this study is to calculate and measure the resultant radial force generated during a deep hole drilling operation. The forces are calculated with the aid of a calculation program and test-runs on a number of drills. This report presents the calculated magnitude and direction of the resultant radial force duringentrance, full intersection and at the exit of the workpiece. In addition to the measured values of theresultant radial force during entry and full intersection. Four different drill geometries are evaluated which of two are competitor drills. A deep hole drill geometry is re-modified in aspect to drill stability based on the outcome of the measured and calculated results. The results acquired from the performed calculation and measurements of the resultant showed that the resultant radial force acts in an angular direction that was outside the range between the support pads. This true for three of the four evaluated drill geometries. There were minor differences between the measured and calculated forces which enforce the reliability of the used calculation program. The modified drill geometry of a deep hole drill gave an indication of which geometry variables have impact on the resultant radial force magnitude and angular direction. The data presented in this report can be a base for future development of a deep hole drill toolgeometry in regard to the resultant radial force. Variables affecting the calculated results and theresultant radial force are presented and discussed. The study is concluded with suggestions of futurework based on the acquired data.

O desempenho das endopróteses vasculares está relacionado diretamente à sua força radial. Esta é uma importante propriedade mecânica destes dispositivos médicos, influenciada por características da matéria-prima, pelos parâmetros de processamento empregados e pela morfologia do produto. Em um ensaio de força radial, determina-se a força necessária para comprimir e para expandir uma endoprótese, ou seja, em função da variação do seu diâmetro é medida a força envolvida. Uma característica desejada nestes ensaios é que a endoprótese se comprima e se expanda de forma homogênea, mantendo sempre sua seção na forma circular, condição esta que a maioria dos métodos hoje utilizados não atende. O presente trabalho buscou desenvolver um método para ser utilizado na determinação da força radial de endopróteses aórticas. Para tanto, um dispositivo composto por uma cinta polimérica acoplada a uma máquina universal de ensaios foi criado. Para verificar a manutenção da forma circular da endoprótese, imagens foram obtidas no decorrer do ensaio. Os resultados mostraram que o dispositivo desenvolvido é capaz de manter a forma circular das endopróteses durante todo o ensaio. Para examinar a capacidade do dispositivo em detectar diferenças nas forças radiais apresentadas por endopróteses em diferentes condições, foram realizados dois estudos, um variando o diâmetro dos fios (0,2, 0,3 e 0,4 mm) utilizados na fabricação das endopróteses e outro variando o tempo de tratamento térmico (30, 45 e 60 min) das endopróteses. Sabendo-se também que as propriedades elásticas da matéria-prima (Nitinol) têm relação direta com a força radial que as endopróteses apresentam, os resultados dos testes de força radial das amostras foram confrontados com ensaios mecânicos de carregamento e descarregamento nos fios da matéria-prima. Os resultados indicaram que o dispositivo foi capaz de detectar diferenças entre valores de força radial com amostras em diferentes condições (tanto de diâmetro de fio como de tratamento térmico) e que os resultados obtidos foram coerentes com testes de carregamento e descarregamento realizados nas amostras de matéria-prima. / The performance of vascular endoprosthesis is directly related to their radial force that is an important mechanical property of these medical devices. It is influenced by characteristics of the raw materials, the processing parameters and the morphology of the final product. The load necessary to compress and expand an endoprostheses is determined by a radial force test, which the load involved is measured by variation of its diameter. A characteristic required during these tests is homogenous compression and expansion of the endoprostheses maintaining its diameter value, in which most methods do not attend it. The aim of this study was develop a method to determine the radial force of aortic endoprostheses. Thus, a device composed with polymer film-type connected a universal test machine was created. Results showed that device developed is able to maintain the circular section (diameter) of the endoprostheses after test. Two studies were performed in order to check the devices’s ability and detect differences in radial forces of the endoprosthesis produced by different conditions. The first condition presented the varying of the wire diameter (0.2, 0.3 and 0.4mm), that was used in the production of the endoprosthesis, and the second one showed different times of heat treatment (30, 45 and 60 min). It is also well known that the elastic properties of the raw material (Nitinol) are directly related to the radial force presented by endoprosthesis. So, samples were compared with wire loading and unloading mechanical tests. Results indicated that the device was able to detect difference among values of radial force in samples at different conditions (both wire diameter and heat treatment time) and they showed consistence of loading and unloading tests performed on samples of raw material.

O desempenho das endopróteses vasculares está relacionado diretamente à sua força radial. Esta é uma importante propriedade mecânica destes dispositivos médicos, influenciada por características da matéria-prima, pelos parâmetros de processamento empregados e pela morfologia do produto. Em um ensaio de força radial, determina-se a força necessária para comprimir e para expandir uma endoprótese, ou seja, em função da variação do seu diâmetro é medida a força envolvida. Uma característica desejada nestes ensaios é que a endoprótese se comprima e se expanda de forma homogênea, mantendo sempre sua seção na forma circular, condição esta que a maioria dos métodos hoje utilizados não atende. O presente trabalho buscou desenvolver um método para ser utilizado na determinação da força radial de endopróteses aórticas. Para tanto, um dispositivo composto por uma cinta polimérica acoplada a uma máquina universal de ensaios foi criado. Para verificar a manutenção da forma circular da endoprótese, imagens foram obtidas no decorrer do ensaio. Os resultados mostraram que o dispositivo desenvolvido é capaz de manter a forma circular das endopróteses durante todo o ensaio. Para examinar a capacidade do dispositivo em detectar diferenças nas forças radiais apresentadas por endopróteses em diferentes condições, foram realizados dois estudos, um variando o diâmetro dos fios (0,2, 0,3 e 0,4 mm) utilizados na fabricação das endopróteses e outro variando o tempo de tratamento térmico (30, 45 e 60 min) das endopróteses. Sabendo-se também que as propriedades elásticas da matéria-prima (Nitinol) têm relação direta com a força radial que as endopróteses apresentam, os resultados dos testes de força radial das amostras foram confrontados com ensaios mecânicos de carregamento e descarregamento nos fios da matéria-prima. Os resultados indicaram que o dispositivo foi capaz de detectar diferenças entre valores de força radial com amostras em diferentes condições (tanto de diâmetro de fio como de tratamento térmico) e que os resultados obtidos foram coerentes com testes de carregamento e descarregamento realizados nas amostras de matéria-prima. / The performance of vascular endoprosthesis is directly related to their radial force that is an important mechanical property of these medical devices. It is influenced by characteristics of the raw materials, the processing parameters and the morphology of the final product. The load necessary to compress and expand an endoprostheses is determined by a radial force test, which the load involved is measured by variation of its diameter. A characteristic required during these tests is homogenous compression and expansion of the endoprostheses maintaining its diameter value, in which most methods do not attend it. The aim of this study was develop a method to determine the radial force of aortic endoprostheses. Thus, a device composed with polymer film-type connected a universal test machine was created. Results showed that device developed is able to maintain the circular section (diameter) of the endoprostheses after test. Two studies were performed in order to check the devices’s ability and detect differences in radial forces of the endoprosthesis produced by different conditions. The first condition presented the varying of the wire diameter (0.2, 0.3 and 0.4mm), that was used in the production of the endoprosthesis, and the second one showed different times of heat treatment (30, 45 and 60 min). It is also well known that the elastic properties of the raw material (Nitinol) are directly related to the radial force presented by endoprosthesis. So, samples were compared with wire loading and unloading mechanical tests. Results indicated that the device was able to detect difference among values of radial force in samples at different conditions (both wire diameter and heat treatment time) and they showed consistence of loading and unloading tests performed on samples of raw material.

O desempenho das endopróteses vasculares está relacionado diretamente à sua força radial. Esta é uma importante propriedade mecânica destes dispositivos médicos, influenciada por características da matéria-prima, pelos parâmetros de processamento empregados e pela morfologia do produto. Em um ensaio de força radial, determina-se a força necessária para comprimir e para expandir uma endoprótese, ou seja, em função da variação do seu diâmetro é medida a força envolvida. Uma característica desejada nestes ensaios é que a endoprótese se comprima e se expanda de forma homogênea, mantendo sempre sua seção na forma circular, condição esta que a maioria dos métodos hoje utilizados não atende. O presente trabalho buscou desenvolver um método para ser utilizado na determinação da força radial de endopróteses aórticas. Para tanto, um dispositivo composto por uma cinta polimérica acoplada a uma máquina universal de ensaios foi criado. Para verificar a manutenção da forma circular da endoprótese, imagens foram obtidas no decorrer do ensaio. Os resultados mostraram que o dispositivo desenvolvido é capaz de manter a forma circular das endopróteses durante todo o ensaio. Para examinar a capacidade do dispositivo em detectar diferenças nas forças radiais apresentadas por endopróteses em diferentes condições, foram realizados dois estudos, um variando o diâmetro dos fios (0,2, 0,3 e 0,4 mm) utilizados na fabricação das endopróteses e outro variando o tempo de tratamento térmico (30, 45 e 60 min) das endopróteses. Sabendo-se também que as propriedades elásticas da matéria-prima (Nitinol) têm relação direta com a força radial que as endopróteses apresentam, os resultados dos testes de força radial das amostras foram confrontados com ensaios mecânicos de carregamento e descarregamento nos fios da matéria-prima. Os resultados indicaram que o dispositivo foi capaz de detectar diferenças entre valores de força radial com amostras em diferentes condições (tanto de diâmetro de fio como de tratamento térmico) e que os resultados obtidos foram coerentes com testes de carregamento e descarregamento realizados nas amostras de matéria-prima. / The performance of vascular endoprosthesis is directly related to their radial force that is an important mechanical property of these medical devices. It is influenced by characteristics of the raw materials, the processing parameters and the morphology of the final product. The load necessary to compress and expand an endoprostheses is determined by a radial force test, which the load involved is measured by variation of its diameter. A characteristic required during these tests is homogenous compression and expansion of the endoprostheses maintaining its diameter value, in which most methods do not attend it. The aim of this study was develop a method to determine the radial force of aortic endoprostheses. Thus, a device composed with polymer film-type connected a universal test machine was created. Results showed that device developed is able to maintain the circular section (diameter) of the endoprostheses after test. Two studies were performed in order to check the devices’s ability and detect differences in radial forces of the endoprosthesis produced by different conditions. The first condition presented the varying of the wire diameter (0.2, 0.3 and 0.4mm), that was used in the production of the endoprosthesis, and the second one showed different times of heat treatment (30, 45 and 60 min). It is also well known that the elastic properties of the raw material (Nitinol) are directly related to the radial force presented by endoprosthesis. So, samples were compared with wire loading and unloading mechanical tests. Results indicated that the device was able to detect difference among values of radial force in samples at different conditions (both wire diameter and heat treatment time) and they showed consistence of loading and unloading tests performed on samples of raw material.

Switched reluctance motors (SRMs) possess many desirable qualities for the long-term sustainability of electrified transportation such as cheap production costs and simple, robust configurations. However, high acoustic noise and torque ripple are two performance imperfections that have prevented the widespread implementation of SRMs. This thesis investigates design techniques to reduce the acoustic noise produced by an 8/6 SRM while also analyzing the impact each design has on the motor’s performance. The fundamentals of SRMs are discussed including the operating principles, modelling and control strategies. The multiphysics finite element analysis (FEA) toolchain used to accurately model acoustic noise and vibrations of SRMs is described. Using the network of FEA tools, nodal forces and natural frequencies of a four phase 8/6 SRM are analyzed to study the acoustic noise and vibration behaviours. The FEA process is validated experimentally by matching measured vibration modes and acoustic noise sound pressure level (SPL) with FEA numerical results. Through inspiration from an extensive literature review, various design techniques are applied to a baseline four phase 8/6 SRM and compared for both acoustic noise reduction and EM performance criteria. The investigated designs were split into two categories, stator-housing modifications that aim to increase the stiffness of the assembly and rotor modifications that aim to reduce the magnitude of radial forces while preserving performance. The best design strategies as determined by the comparative analysis were then further optimized to combine the best techniques together for the 8/6 SRM. The proposed structural improvements included the modifications of the stator yoke shape along with increasing the number of fastening components involved in the assembly. Additionally, an iterative procedure for the parametric modelling of windows introduced to the rotor poles is outlined. The best design considerations are combined to create the design of a novel 8/6 SRM which significantly reduces the acoustic noise produced by the motor with little impact to performance. / Thesis / Master of Applied Science (MASc)

Switched reluctance machines (SRMs) are gaining increasing interest in industrial applications due to their low manufacturing cost, simple and robust structure, excellent fault-tolerant capability, and reliable operation in high-temperature operating environments. However, the inherent pulsative torque and radial force lead to the well-known torque ripples and acoustic noise issues. Although there are numerous advanced methods to address the above two issues, the high nonlinearity inevitably brings difficulties in controlling the SRMs. Since the linear SRM voltage and toque equations are simple, it would be beneficial to explore the control algorithm by using such simple linear model. The application of the linear torque model is firstly explored. To utilize such simple model, the connections between the linear toque model and the nonlinear torque model are built through the mapping. The features of these mapping curves are studied in detail. Applying the linear torque equation to generate the reference currents in the optimization-based torque sharing function method shows a significant reduction of the time consumption in solving the bi-optimization problem. Later, the complete equivalent linear SRM model is constructed by introducing the linear voltage equation and corresponding mapping. Since the linear model is easy to predict the behaviour of SRMs, it is beneficial to apply such model in the model predictive torque control (MPTC) methods. The application of the equivalent linear model in the finite control set (FCS) MPTC method shows a low computational burden and occupies less storage space. Besides, the improved switching table in the proposed FCS MPTC method also enhances the torque control performance in high-speed operation conditions. To further reduce the torque ripples, the continuous control set (CCS) MPTC method is developed based on the constructed equivalent linear SRM model. The impossibility in analytically solving the optimization problem in the CCS MPTC method if using the original nonlinear SRM model is innovatively addressed by using the equivalent linear SRM model and properly modifying the cost function. Extensive simulation and experimental results prove the low-ripple feature of the proposed CCS MPTC method in a wide speed range. The high nonlinearity also makes the current control of SRM drives difficult. An intersection-method-based current controller is presented to ensure good current tracking performance for SRMs. The employed adaptive flux-linkage observer makes this current controller show robust performance when there is a deviation on the employed flux-linkage characteristics. Finally, the key but unmeasurable radial force information for the advanced acoustic reduction method is reconstructed based on the measured flux-linkage curves and some core relationship. This core relationship, which is between the square root of the radial force and the flux-linkage, is explored in detail. Simulation results reveal that the proposed method shows good radial force estimation accuracy when there is even 50% airgap length variation. / Thesis / Doctor of Philosophy (PhD)

No description available.

Variations in vehicle noise, vibration and harshness (NVH) response from one vehicle to the next can have significant impact on an automotive company’s profile and profitability. The warranty claims due to excessive NVH response end up costing the manufacturers a large sum of money each year. In addition, the OEM will suffer a larger financial loss due to the poor perception of quality and customer dissatisfaction with their products due to the unacceptable NVH response. Therefore, measures must be taken to ensure less warranty claims and higher levels of customer satisfaction. This research focuses on aspects of design variations that are costly or difficult to be avoided in the design process such as variations with rubber parts and variations due to rotating components. Vibrations induced at the tire/wheel assembly due to variations in the radial and tangential forces and radial runout are responsible for the driverelt vibrations that can lead to a large number of warranty claims. The purpose of this research is to improve the process of determining and analyzing vibration sources in the tire/wheel assembly in order to benefit the automotive manufacturer during the development and manufacturing phases. This research identifies the relationship between non-uniformity forces of the tire/wheel assemblies and the driverelt vibrations during typical highway driving speeds. The contribution from each assembly location is analyzed and sensitivities are determined. A Monte Carlo process is used to predict numerous non-uniformity properties that are statistically representative of the assembly properties that can be expected at the manufacturing plant. The Monte Carlo produced non-uniformity properties are combined with the sensitivities to predict driverelt vibrations that can be expected from vehicles leaving the manufacturing plant. This process provides the tools to determine an acceptable level of non-uniformities based on targets for interior vibration levels or determine if the vehicle sensitivities to non-uniformities need to be improved.

Closer attention has been given to the acoustic noise performance of electric motors as electrified powertrains penetrate into the transportation system. Particularly, switched reluctance machines (SRMs) introduce a new challenge to the acoustic noise aspects given that the radial force harmonics can excite the natural frequencies of the main circumferential modes. A practical understanding of the radial force density decomposition is crucial in identifying the primary source of acoustic noise at different operating points, and it is one of the contributions of this thesis. An analytical expression is introduced to identify the temporal harmonic orders that excite different spatial mode shapes. The mode excitation is investigated along with the sound pressure level (SPL) produced by the primary vibrating mode shapes. Acoustic noise characteristics for each mode and the corresponding natural frequency at different speeds have been analyzed by using a waterfall plot. The acoustic noise generation by conventionally controlled SRMs prevents its use on applications where acoustic comfort is required. Acoustic noise is radiated by the stator frame when a vibration mode is excited by the respective spatial order at a forcing frequency that is close to the stator's modal natural frequency. The excitation surface wave is the radial force density waveform as a function of time and spatial position. From the harmonic content analysis, a phase radial force shaping method is for switched reluctance machines is proposed. A generic function for the radial force shape is identified, whose parameters are calculated by an optimization algorithm to minimize the torque ripple for a given average torque. From the phase radial force, a current reference is obtained. The proposed methodology is experimentally validated, with a four-phase 8/6 SRM, by acoustic noise measurements at different speeds and load torque conditions. / Thesis / Doctor of Philosophy (PhD)

This diploma thesis deals with problematics of the radial force effect on the runner and possibilities of the force reduction. Some pump modifications were proposed and changes of radial force magnitude in reverse blocking state and optimal flow state were examined in consequence. Following investigation was focused on the new modifications regarding to the pump efficiency and its characteristics stability. All results were carried out using the Solidworks, the Fluent and the Microsoft Excel software.