The research program involved both numerical and experimental work. The numerical analysis was conducted to simulate the static and dynamic behaviour of the 81 m meteorological FRP guyed tower under wind and ice loading. The FRP tower consisted of 16 segments each made of 3 cells connected together to form an equilateral triangle having equal sides of 450 mm. The segments were interconnected using internal sleeves. Various non-linear finite element models were developed to study a number of design parameters for the 81 m FRP tower such as, different laminates containing a variety of stacking sequences of laminate orientations with various thicknesses, different cable diameters, and appropriate guy cable spacing levels. The effect of pre-stressing the guy cables up to 10 % of their breaking strength was investigated. The effect of fibre volume fraction on the design of the FRP tower was also examined. Furthermore, an 8.6 m FRP tower segment was designed using the finite element analysis and subject to the same loading conditions experienced by the bottom section of the 81 m FRP tower. A modal analysis was carried out for both the 8.6 m FRP tower segment with and without a mass on the top as well as for the 81 m FRP guyed tower to evaluate the vibration performance of these towers. The experimental work involved extensive material testing to define the material properties for use in the analysis of the 81 m FRP tower. It also involved the design and fabrication of a special collapsible mandrel for fabricating the FRP cells for the 8.6 m tower segment. The 8.6 m tower was tested horizontally under static lateral loading to 80 % of its estimated failure load using a “whiffle tree” arrangement, in order to simulate a uniformly distributed wind loading. Later, the same FRP tower was erected in a vertical position and was tested with and without a mass on top under dynamic loading to obtain the natural frequencies. Lastly, a comparative study was conducted between two 81 m FRP towers having different fibre volume fractions and a steel tower having a circular cross section.

ASCE Manual No.74 (2010) and the Electric Power Research Institute (EPRI, 1997) provide methods for calculating the unbalanced longitudinal loads on a transmission line due to a wire breakage. The calculated loads from the two are different. In this study, a simplified transmission line was created using the equivalent geometric properties of a detailed transmission line. Non-linear dynamic analyses of the 10-span simplified transmission line due to cable breakage events in the first span were studied using ANSYS. The analyzed longitudinal loads were found to vary for different S/S, S/I, and K’s as specified in the EPRI. An equation for the longitudinal load factor as a function of the S/S, S/I, and K was then formulated based on the analysis. The longitudinal load factors from the formulated equation were found to be almost double those given by the ASCE manual and comparable to those calculated using the EPRI formulation.

The research program involved both numerical and experimental work. The numerical analysis was conducted to simulate the static and dynamic behaviour of the 81 m meteorological FRP guyed tower under wind and ice loading. The FRP tower consisted of 16 segments each made of 3 cells connected together to form an equilateral triangle having equal sides of 450 mm. The segments were interconnected using internal sleeves. Various non-linear finite element models were developed to study a number of design parameters for the 81 m FRP tower such as, different laminates containing a variety of stacking sequences of laminate orientations with various thicknesses, different cable diameters, and appropriate guy cable spacing levels. The effect of pre-stressing the guy cables up to 10 % of their breaking strength was investigated. The effect of fibre volume fraction on the design of the FRP tower was also examined. Furthermore, an 8.6 m FRP tower segment was designed using the finite element analysis and subject to the same loading conditions experienced by the bottom section of the 81 m FRP tower. A modal analysis was carried out for both the 8.6 m FRP tower segment with and without a mass on the top as well as for the 81 m FRP guyed tower to evaluate the vibration performance of these towers. The experimental work involved extensive material testing to define the material properties for use in the analysis of the 81 m FRP tower. It also involved the design and fabrication of a special collapsible mandrel for fabricating the FRP cells for the 8.6 m tower segment. The 8.6 m tower was tested horizontally under static lateral loading to 80 % of its estimated failure load using a “whiffle tree” arrangement, in order to simulate a uniformly distributed wind loading. Later, the same FRP tower was erected in a vertical position and was tested with and without a mass on top under dynamic loading to obtain the natural frequencies. Lastly, a comparative study was conducted between two 81 m FRP towers having different fibre volume fractions and a steel tower having a circular cross section.

Tierärztl. Hochsch., Diss., 2003--Hannover.

The Master's thesis deals with the creation of the numerical model that serves to analysis of the acoustic properties of separating construction of a wooden structure. The work includes theoretical basis for solving the subject, it discusses the airborne sound insulation of separating structures, focuses on wooden buildings, describes a computing environment ANSYS and model creation in it. More variants of model were compiled, CLT panel and frame construction. Model itself is using scripting language APDL and each step of creation is described. The results of numerical simulations describe the distribution of pressure in front and behind the separation construction. Results are compiled into graphs and single value of weighted airborne sound insulation is evaluated. In conclusion individual results of model variants are compared, model accuracy improvements are discussed.

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No description available.

This thesis is a measurement evaluation type of project in which to perform a harmonic response analysis were the results will be compared to measurement data to verify if the ANSYS model is realistic in terms of dynamics. This includes proposing the different parameters that will affect the results of the comparison as well as how to improve further models. In 2014 Atlas Copco received a special customer order of a ST1530 loader with a Detroit engine instead of a Cummins engine which is commonly used in the ST1530. New dynamic analyses had to be performed by the Applied Mechanics Group, regarding harmonic response using data from a measurement of a ST1520 loader with a Detroit engine. A new design of the engine cradle was developed after several analysis iterations. In February 2015, new measurements were performed on the loader with the right Detroit engine and a new engine cradle. There are two different comparison tools/methods used in this thesis, one that consists of comparing the difference between the mean average value of both the ANSYS and the measurements results. The other tool/method is more accurate since it compares both the variation between the peaks and also the offset of the frequency. Results show that the measurement results in 800 rpm were very compatible with the analysis results in ANSYS, meanwhile at high speed the measurement results were only moderately compatible with the analysis results. The vibration in 800 rpm doesn’t exceed the Atlas Copco rule of thumb as opposed to the 2173 rpm. This is only considering the cradle, the cooler however consists of higher vibrations than the measurement data. Their rule of thumb is defined as a boundary for the maximum allowable vibration values. The model could’ve been a lot more accurate if the use of CAD models of both the engine and the cooler were implemented in the analysis. This is desirable but it does not work all the time as companies for these products can not issue a CAD model due to, e.g. Patents and such. / Denna avhandling är en mätutvärdering där man ska utföra en harmonisk responsanalys vars resultat kommer att jämföras med mätdata för att kontrollera om ANSYS modellen är realistisk i dynamiska termer. Detta inkluderar även att man ska föreslå de olika parametrar som kommer att påverka resultatet av jämförelsen samt hur man kan förbättra ytterligare modeller. Under 2014 erhöll Atlas Copco en speciell kundorder med en ST1530 lastare där man ville ha en Detroitmotor istället för en Cumminsmotor som ofta används i ST1530. Detta resulterar i att nya dynamiska analyser måste utföras av Applied Mechanics Group, angående harmonisk respons där man använde data ifrån en mätning av en ST1520 lastare med Detroit motor. En ny utformning av motorvaggan utvecklades efter flera iterationer. I februari 2015 så utfördes nya mätningar på lastaren med rätt Detroitmotor och den nya motorvaggan. Två olika jämförelseverktyg/metoder användes i denna avhandling. Det första verktyget/metoden testades, som består av att jämföra skillnaden mellan det genomsnittliga medelvärdet av både ANSYS och mätresultat. Det andra verktyget/metoden användes för att den är mer exakt eftersom den jämför både variationen mellan vibrationstopparna och även förskjutningen i frekvens. Resultaten visar att mätresultaten i låg hastighet (800 rpm) var mycket förenliga med analysresultaten i ANSYS, däremot vid hög hastighet (2173 rpm) var mätresultaten bara måttligt förenliga med analysresultaten. Vibrationerna i 800 rpm överstiger inte Atlas Copcos tumregel till skillnad från 2173 rpm, detta är bara med tanke på vaggan. Kylaren har däremot högre vibrationer än mätdata.Denna tumregel är definierad som en avgränsning för maximalt tillåtna vibrationsvärden. Modellen kunde varit mycket mer exakt om man hade implementerat CAD-modeller av både motorn och kylaren i analysen. Detta är önskvärt men funkar inte hela tiden då företagen för dessa produkter inte kan ge ut en CAD modell, pga. t.ex. patent eller liknande.

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No description available.