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Pulsed Flow Jet Impingement Cooling: Evaluation Of Heat Transfer Performance, Michael Lee Hamman

Theses and Dissertations

This thesis presents findings from an experimental and numerical investigation into merits of pulse coolant flow as an improvement to impingement cooling. A series of simulations were conducted at Re=12k and 30k for frequencies up to 20Hz and amplitude ratios up to 70% of mean mass flow and standoff and nozzle spacing equal to three diameters. Square waveforms were found to degrade at low frequencies near 1Hz, rendering the use of square waveforms as an invalid mass flow specifications for inlet boundaries in computational predictions. The Power Consumption Ratio is introduced for comparing pulse and steady flow configuration’s energy consumption. …

Numerical Study Of Thermal Performance Improvement By Novel Structures In The Building Energy Storage Systems, Junling Xie

Theses and Dissertations

In this work, numerical studies were conducted to investigate the effectiveness of two fin-like novel structures used for heat-transfer enhancement in two building energy storage systems including thermal energy storage and battery energy storage.

Firstly, thin layer ring structure was numerically investigated for thermal performance improvement in the thermal energy storage. From the results obtained in this study, the area ratio can be increased by 4% when using the thin layer ring during the same time period. The thin layer ring structure can shorten ice formation period and increase its efficiency. Further study was conducted for the factorial analysis of …