<p dir="ltr">This study encompasses the design and dynamic analysis of a previously used compact, portable vibrating plate machine. Utilizing Siemens NX 2021 for the precise modeling of the machine's components, the design prioritized simplicity and functionality, resulting in a 450 mm x 450 mm aluminum alloy structure, suitable for a wide range of research applications. A detailed modal analysis, conducted to ascertain the system's natural frequencies, revealed six predominant modes, ensuring operational frequencies of 110 Hz to 130 Hz were strategically avoided to mitigate resonance risks. Complementing this, harmonic response analysis evaluated the system's behavior under an applied cyclic load, confirming the suitability of the chosen actuator, model VL181206-160H, which provides optimal vibrational force without over stressing the machine. The findings affirm the machine's capability to perform efficiently within the target frequency range, with the design and selected actuator offering a robust solution for consistent and safe vibrational analysis, essential for field and laboratory applications.</p>

Digitized by Kansas State University Libraries

Dissertation made openly available per email from author, 7/22/2016.

published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy

published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy

High levels of machine noise result in health issues for those people exposed to the machine for extended periods. Machine noise is becoming a more significant design consideration, often because of legislative requirements. Decanting centrifuges are machines with a rotating bowl. They have a number of noise sources, the most significant being structural noise, vortex/turbulence noise and siren noise. Due to the size, mass and speed of the rotating bowl, the bowl is the main source of structural noise. The structural noise is produced by all surfaces that are directly coupled to the bowl’s bearings. Due to the speed of rotation of the bowl, the turbulence from the various trailing edges generates broad spectrum vortex noise. Siren noise due to air flow through the bowl also generates significant noise especially at the lower harmonics of the bowl rotation frequency. Strategies to reduce decanter machine noise include: • Decoupling the surfaces of the from the main bearings of the rotating bowl and hence reduce the amount of structurally transmitted noise. • Smoothing the surface of the bowl to minimise the edges that produce vortices that are shed and produce vortex/turbulence noise. • As siren noise is produced due to flow through the rotating bowl, which is integral to the function of the decanter, the exit ports should be designed so that the noise is produced within parts of the sound spectrum that have low noise levels.

No description available.

No description available.

No description available.

No description available.