No description available.

Digitized by Kansas Correctional Industries

This master thesis has been written to develop a new pipe support for pipe systems in the process industry. The purpose was to relieve pumps or other sensitive equipment from elevated forces or moments that may cause failure. The elevated forces or moments occur due to the weight of the piping, the weight of the medium and expansion due to elevated temperatures. The support is mainly designed to be implemented in a 90 degree bend but they can also be implemented in straight pipes with small adjustments of the attachment between the support and the pipe. Six different complete concepts were developed and put through different elimination matrices and evaluated against a requirement specification. The final design was calculated to withstand the forces and moments from a worst case scenario. The concept is in need of further development and testing before it can be implemented in projects. It is necessary to investigate if the clamps can withstand the working load in the new design. The concept should also be tested possibly by a prototype.

Digitized by Kansas Correctional Industries

No description available.

No description available.

No description available.

This research focuses on an advanced optical light pipe daylighting system as a means to deliver natural light at the back of deep-plan office buildings (15ft to 30ft), using optimized geometry and high reflective materials. The light pipe configurations follow a previous study at the Lawrence Berkeley National Laboratory (Beltr??n et al., 1997). The current system is designed for College Station, TX (lat: 30?? 36??N), with predominantly mostly sunny sky conditions. This work consists of the monitoring of two scale models simulating a portion of a multi-story office building with open-plan configuration, with interior dimensions 30ft x 20ft x 10ft, built at 1:4 of its real scale, one of the models being the reference case and the other the test case where the light pipe system is placed. The main objectives of this thesis are (a) to examine this daylighting system comparative to the reference case, taking measurements for longer periods than the study at LBNL, as well as to collect detailed data of its performance under different weather conditions and with different materials; (b) to evaluate the visual comfort and possible glare problems of the light pipe system through photographic evaluation and the conduction of a survey that provides people??s opinions and suggestions about the daylighting system. The light pipe system demonstrated a higher performance than the reference case in terms of appropriate levels of light and people??s preferences. The illuminance at the workplane level showed to be adequate with any of the two different diffusing materials used to spread the light into the room. The light pipe without a diffuser was the other condition observed to further understand the bounces of the sunbeam inside the reflective chamber and its consequences on the lighting output. Recommended standards for office spaces with VDT screens together with the analysis of the daylight system, led to preliminary suggestions on how to integrate the light pipe system in an open-plan office configuration. Further study is indicated to reach the complete potential of this advanced optical light pipe that ties illuminance quality with energy savings through the integration of daylight and electric light systems.

Continued development of highly compact and powerful electronic components has led to the need for a simple and effective method for controlling the thermal characteristics of these devices. One proposed method for thermal control involves the use of a micro heat pipe system containing a working fluid with physical properties having been speciffcally selected such that the heat pipes, as a whole, vary in effective thermal conductance, thereby providing a level of temperature regulation. To further explore this possibility, a design scenario with appropriate constraints was established and a model developed to solve for the effective thermal conductance of individual heat pipes as a function of evaporator-end temperature. From the results of this analysis, several working fluids were identified and selected from a list over thirteen hundred that were initially analyzed. Next, a thermal circuit model was developed that translated the individual heat pipe operating characteristics into the system as a whole to determine the system level effects. It was found that none of the prospective fluids could completely satisfy the established design requirements to regulate the device temperature over the entire range of operating conditions. This failure to fully satisfy design requirements was due, in large part, to the highly constrained nature of problem definition. Several fluids, however, did provide for an improved level of thermal control when compared to the unmodified design. Suggestions for improvements that may lead to enhanced levels of thermal control are offered as well as areas that are in need of further research.

Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2004. / Includes bibliographical references (leaves 175-184). Also available in electronic version. Access restricted to campus users.