Engineering Commons^™

Experimental Investigation Of Cryogenic Convection And Boiling In Traditionally And Additively Manufactured Rocket Engine Cooling Channels, Armando Sandoval

Open Access Theses & Dissertations

The Center for Space Exploration and Technology Research at the University of Texas at El Paso, has designed, built, and optimized an experimental high heat flux test facility to investigate the heat transfer coefficient of liquid methane and other cryogenic propellants for regenerative cooled rocket engine design. The system is composed of a copper conduction based thermal concentrator that delivers heat flow into a single sub-scaled cooling channel (test article). This study focuses on optimizing this design of the high heat flux test facility to develop a more accurate method for measuring the conductive heat flow going into the cooling …

Flexible Residential Test Facility: Impact Of Infiltration And Ventilation On Measured Cooling Season Energy And Moisture Levels (2016), Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Originally published in January 2014, this revision of the report clarifies and corrects references to Standard 62.2 as the 2013 version (62.2-2013), and it corrects the total CFM requirement for the subject buildings under the standard. Further, two plots have been updated to distinguish between the mechanical CFM and the total CFM required for the subject buildings under Standard 62.2-2013.

Final Report: Cooling Seasonal Energy And Peak Demand Impacts Of Improved Duct Insulation On Fixed-Capacity (Seer 13) And Variable-Capacity (Seer 22) Heat Pumps, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Previous phase 1, 2, and 3 research identified that duct conductive losses to an attic environment imposed greater relative energy losses for the variable-capacity systems compared to the fixed-capacity systems (Cummings and Withers 2011) because of the longer dwell time of conditioned air in the ducts. The purpose of the Phase 4 experiments reported here was to see if duct R-value enhancement would benefit the overall operating efficiency of the variable-capacity system relatively more than the fixed-capacity system. The current Phase 4 experiments (the primary focus of this report) found that this was a secondary effect.

Evaluation Of The Impact Of Slab Foundation Heat Transfer On Heating And Cooling In Florida, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The U.S. Department of Energy's Building America Partnership for Improved Residential Construction (BA-PIRC) performed experiments in the Florida Solar Energy Center's Flexible Residential Test Facility intended to assess for the first time (1) how slab-on-grade construction influences interior cooling in a cooling-dominated climate and (2) how the difference in a carpeted versus uncarpeted building might influence heating and cooling energy use.

Optimal Design Of Ipm Motors With Different Cooling Systems And Winding Configurations, Alireza Fatemi, Dan M. Ionel, Nabeel Demerdash, Thomas W. Nehl

Electrical and Computer Engineering Faculty Research and Publications

Performance improvement of permanent magnet (PM) motors through optimization techniques has been widely investigated in the literature. Oftentimes the practice of design optimization leads to derivation/interpretation of optimal scaling rules of PM motors for a particular loading condition. This paper demonstrates how these derivations vary with respect to the machine ampere loading and ferrous core saturation level. A parallel sensitivity analysis using a second-order response surface methodology followed by a large-scale design optimization based on evolutionary algorithms are pursued in order to establish the variation of the relationships between the main design parameters and the performance characteristics with respect to …

The Effect Of Confinement On The Development Of An Axisymmetric Wall Jet In Confined Jet Impingement, Tianqi Guo

Open Access Theses

Impinging jets have been widely used in the industry for cooling, heating, drying and many other purposes due to their excellent level of mass and heat transfer capacities. When issued into a confinement gap fully filled with working liquid, which is a typical configuration for the compact cooling devices designed to handle the extremely high heat fluxes generated by continuously working electronic components, they are classified as submerged confined impingement jets. Though the complicated flow field induced by the jet has attracted enormous amount of research efforts from heat transfer as well as fluid dynamics points of view, many key …

Development Of Intermediate Cooling Technology And Its Control For Two-Stand Plate Rolling, Fei Zhang, Wei Yu, Tao Liu

Faculty of Engineering and Information Sciences - Papers: Part A

In a plate rolling production line, thermomechanically controlled processing is critical for plate quality. In this paper, a set of intermediate cooling equipment of a two-stand plate mill with super density nozzles, medium pressure, and small flow is developed. Based on a simplified dynamic model, a cooling control scheme with combined feedforward, feedback, and adaptive algorithms is put forward. The new controlled rolling process and the highly efficient control system improve the controlled rolling efficiency by an average of 17.66%. The proposed intermediate cooling system can also effectively inhibit the growth of austenite grain, improve the impact toughness and yield …

Development Of A Novel Phase Change Material Emulsion For Cooling Systems, Jingjing Shao, Jo Darkwa, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, a novel phase change material emulsion (PCE-10) consisting of an organic PCM (RT10) and water has been developed. Its thermophysical properties such as heat of fusion, viscosity and sub-cooling temperature have been established. The chemical stability during both storage and discharge periods have also been evaluated. The results indicate low sub-cooling temperature and relatively long period of stability without any sign of segregation but the viscosity was found to be much higher than that of water.Further improvement and experimental studies into its flow characteristics are therefore being encouraged.

An Experimental Investigation Of Heat Transfer For Arrays Of Impingement Jets Onto The Featured Surfaces With Cylindrical And Elliptical Raised Surfaces, Marc A. Medina

Honors Undergraduate Theses

This study focuses on multi-jet impingement for gas turbine geometries in which the objective is to understand the influence of the roughness elements on a target surface to the heat transfer. Current work has proven that implementing roughness elements for multi-jet impingement target surfaces has increased heat transfer ranging anywhere from 10-30%. This study has chosen to investigate three different roughness elements, elliptical in cross-section, to compare to smooth surface geometries for multi-jet impingement. An experimental was taken for this study to extend the current knowledge of multi-jet impingement geometries and to further understand the heat transfer performance. A temperature …

Simulation Of An Air Cooled Single-Effect Solar Absorption Cooling System With Evacuated Tube Collectors, Mohsen Jahandardoost

UNLV Theses, Dissertations, Professional Papers, and Capstones

Consistently increasing CO2 emission and ozone depletion from synthetic refrigerants are serious environmental issues challenging the scientific community. Absorption cooling systems give scope of utilizing low grade energy source for generating cooling effect. Solar energy is one of these low grade energy sources and with considering the fact that cooling demand increases with the intensity of solar radiation, solar refrigeration has been considered as a logical solution.

This thesis consists of two different simulation stages, in the first stage, a single effect lithium bromide absorption cooling system with constant cooling capacity is modeled and the effect of ambient and generator …

Cooling And Heating Season Impacts Of Right-Sizing Of Fixed- And Variable-Capacity Heat Pumps With Attic And Indoor Ductwork, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

The U.S. Department of Energy's research team Building America Partnership for Advanced Residential Construction implemented two phases of experiments to examine the cooling and heating seasonal and peak demand performance of a variable-capacity 2-ton SEER 22 heat pump versus a 3-ton variable-capacity SEER 21 heat pump with attic ducts and indoor ducts. The experiments also compared the cooling and heating seasonal and peak demand performance of 2-ton versus 3-ton fixed-capacity SEER 13 heat pumps with attic ducts and indoor ducts.

Validation Of A Cfd Approach For Gas Turbine Internal Cooling Passage Heat Transfer Prediction, Daniel G. Wilde

Master's Theses

This report describes the development and application of a validated Computational Fluid Dynamics (CFD) modelling approach for internal cooling passages in rotating turbomachinery. A CFD Modelling approach and accompanying assumptions are tuned and validated against academically available experimental results for various serpentine passages. Criteria of the CFD modelling approach selected for investigation into advanced internal cooling flows include accuracy, robustness, industry familiarity, and computational cost.

Experimental data from NASA HOST (HOt Section Technology), Texas A&M, and University of Manchester tests are compared to RANS CFD results generated using Fluent v14.5 in order to benchmark a CFD modelling approach.

Capability of …

The Effect Of Nb On The Continuous Cooling Transformation Curves Of Ultra-Thin Strip Castrip© Steels, Kristin R. Carpenter, Chris R. Killmore

Faculty of Engineering and Information Sciences - Papers: Part A

The effect of Nb on the hardenability of ultra-thin cast strip (UCS) steels produced via the unique regime of rapid solidification, large austenite grain size, and inclusion engineering of the CASTRIP^© process was investigated. Continuous cooling transformation (CCT) diagrams were constructed for 0, 0.014, 0.024, 0.04, 0.06 and 0.08 wt% Nb containing UCS steels. Phase nomenclature for the identification of lower transformation product in low carbon steels was reviewed. Even a small addition of 0.014 wt% Nb showed a potent effect on hardenability, shifting the ferrite C-curve to the right and expanding the bainitic ferrite and acicular ferrite phase …

The Optimisation Of The Secondary Cooling Water Distribution With Improved Genetic Algorithm In Continuous Casting Of Steels, Yu-Chun Zhai, Ying Li, Beiyue Ma, C Yan, Zhengyi Jiang

Faculty of Engineering and Information Sciences - Papers: Part A

An improved genetic algorithm is presented for the water consumption of the secondary cooling zone based on the heat transfer model of the off-line bloom caster. This study is to control the existing cooling systems and the steel casting practises in order to produce steel with best possible quality. The fitness function of improved genetic algorithm is founded according to the metallurgical criteria. This algorithm coupled with heat transfer model and metallurgical criteria, added dynamic coding method and self-adapting mutation on the original genetic algorithm can increase water distribution adaptively and improve the process efficiency. The simulation results of T91 …

Heat Transfer And Film Cooling On A Gas Turbine Blade And Shroud, Onieluan Tamunobere

LSU Doctoral Dissertations

At a fixed pressure ratio, the thermodynamic efficiency and net power output of a gas turbine engine increases with an increase in the turbine inlet temperature. Cooling is necessary because of the thermal limits of the engine materials. This research studies through experimentation, the heat transfer and cooling of critical gas turbine components including the shroud and blade tip. In the first phase, the shroud heat transfer behavior and the effectiveness of shroud cooling under the conditions of rotation is undertaken in a single stage turbine at a design rotation speed of 550 rpm, at off-design speeds and for varying …

Fsae Electric Vehicle Cooling System Design, Jeff Lamarre

Williams Honors College, Honors Research Projects

No abstract provided.

Assessment Of Energy Efficient Methods Of Indoor Humidity Control For Florida Building Commission Research, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

This research project was conducted with the primary objective to identify approaches and technologies which can achieve energy-efficient latent cooling in light of code requirements that may increase overall ventilation rates in new Florida homes. This report covers the work of two primary efforts of completing a literature review and testing a few space conditioning methods in a mechanically ventilated building. Results from a literature review provide a list of various approaches to managing the latent load in homes with emphasis on energy efficiency and cost-effectiveness. In addition to a literature review, controlled experiments using four different approaches to space …

Formula Sae Cooling System Design, Lisa Van Den Berg, Brandon Lofaro

Mechanical Engineering

The overall objective of this senior project is to develop, via testing and analysis, a guided process that will aid the Cal Poly Formula SAE team in designing their cooling system. More specifically, a set of designed tests will yield the results necessary in determining a combination of fan and radiator that will achieve appropriate cooling.

A test section that has the capability of interfacing with both the wind tunnel in the Thermal Science Lab and a radiator will be used to facilitate the necessary experiments. The wind tunnel is powered by fan controlled by a variable frequency drive that …

Flexible Residential Test Facility: Impact Of Infiltration And Ventilation On Measured Cooling Season Energy And Moisture Levels, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Air infiltration and ventilation in residential buildings is a very large part of the heating loads, but empirical data regarding the impact on space cooling has been lacking. Moreover, there has been little data on how building tightness might relate to building interior moisture levels in homes in a hot and humid climate. To address this need, BA-PIRC has conducted research to assess the moisture and cooling load impacts of airtightness and mechanical ventilation in two identical laboratory homes in the hot-humid climate over the cooling season.

Energy And Peak Power Reduction From Air Misting Products Applied To Commercial Condensing Units In Hot And Humid Climates, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

A proprietary research project was conducted to evaluate the potential annual and peak energy reduction resulting from the addition of a water misting system applied to supermarket condenser coils in the Florida Power and Light service territory. Tests were performed to evaluate the performance of a mist system under various outdoor conditions over an eight-month period in a hot and humid climate zone. The project measured an average of 2.8% percentage energy savings and average 3.2% utility peak demand reduction. The report discusses why hot and humid climates can expect much lower savings compared to hot and arid climates. One …

Integrated Dehumidification And Downdraft Evaporative Cooling System For A Hot-Humid Climate, Sriraj Gokarakonda, Georgios Kokogiannakis

Faculty of Engineering and Information Sciences - Papers: Part A

Unlike in hot-dry climates, in hot-humid climates evaporative cooling techniques are not readily suitable for space cooling. In order to effectively use evaporative cooling in hot-humid climates, dehumidification of ambient air is necessary before it passes over an evaporative medium for cooling. The present study explores the combined process of dehumidification and evaporation and its effect on thermal comfort in a typical small residential building located in a hot humid climate. A novel system has been investigated with the combination of an Earth Tube Ventilation (ETV) (for pre-cooling of air), a rotary wheel desiccant dehumidifier (for dehumidification) along with a …

Implementation And Analysis Of A 1.4l Turbo Liquid Cooled Cac And Ac Condenser System, Mitchell Zajac

Masters Theses

This project report serves as a continuation and finalization of an overall experience with the design process including working on the development of system components, working with automotive industry leaders, suppliers and dealing with the aspects of business and production feasibility. The development of a dual level cooling concept to apply Centro Richerche Fiat established components on a Chrysler Group vehicle application was the foundation of the design project completed in December 2012 by Matt Cutler and Mitch Zajac. The development of this system aimed to decrease overall vehicle power consumption, minimize overall system packaging space, and to increase vehicle …

Municipal Wastewater Reuse As Makeup To Cooling Towers, David Goldstein, John Casana, Irvine Wei

Irvine W. Wei

At the first Water Reuse Symposium in March 1979 we presented a literature survey on the reuse of municipal wastewater as makeup to circulating cooling systems. We concluded that the wastewater was useable and not excessively costly. Since then we have corresponded with most of the plants in the world who are reusing water this way (we have received information from seven plants). About half the plants surveyed use extensive chlorination and half use no chlorination at all and encourage biological activity. No plants report problems with corrosion even when ammonia is present. The old problem of foam is dying …

Ql+ Body Temperature Regulating Vest Design Report, Ritesh Desai, Brad Gausewitz, Mira Atiya, Jaison Machanickal

Materials Engineering

Patients with spinal cord injuries are often unable to regulate their body temperature. This can be very dangerous when the body reaches temperatures above 104 degrees F. The result is damaging to the human body and can even result in death. Therefore it is necessary to implement external sources of cooling for these individuals who are incapable of reducing their body temperature through normal methods. This two year long thermal vest project is a senior project sponsored by QL+ and began in Fall 2011. QL+ is a not-for-profit organization who focuses on improving the quality of life of those injured …

A Study Of The Continous Cooling Behaviour And Effect Of Preheat And Interpass Temperature On The Haz Of High Strength Quenched And Tempered Steel, Lenka Kuzmikova, Mark Callaghan, Nathan Larkin, Robert Scott, Robert De Jong, Huijun Li, John Norrish

Nathan Larkin

In this study, the continuous cooling phase transformation behaviour of a quenched and tempered armour steel was investigated. A continuous cooling transformation diagram was constructed providing valuable information for predicting microstructural evolution and mechanical properties at different cooling rates during actual welding fabrication. Welding trials were carried out utilising flux-cored arc welding technique in combination with an austenitic stainless steel consumable. The effect of various preheat and interpass temperatures on cooling rate and consequently on the heat affected zone microstructure and mechanical properties of multipass welds were investigated.

Determining Appropriate Heating And Cooling Thermostat Set Points For Building Energy Simulations For Residential Buildings In North America, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Existing building energy simulation tools have a purported tendency to over-predict heating use and, in some cases, to under-predict cooling use, an outcome often attributed to inappropriate assumptions about thermostat management. As a result, a systematic review was conducted for the purposes of determining typical heating and cooling set points for single-family houses in North America. The preliminary consensus results provide an empirical basis for establishing typical inputs for building energy simulation models, increasing prediction accuracy of heating and cooling loads. The results of this review have been applied as default values in the Lawrence Berkeley National Laboratory's Home Energy …

Measured Cooling Performance And Potential For Buried Duct Condensation In A 1991 Central Florida Retrofit Home, Florida Solar Energy Center, David Chasar

FSEC Energy Research Center®

The Florida Solar Energy Center (FSEC) conducted energy performance monitoring of two existing residences in Central Florida that were undergoing various retrofits. These homes were occupied by FSEC researchers and were fully instrumented to yield detailed energy, temperature, and humidity measurements. The data gave feedback about the performance of two levels of retrofit in two types of homes in a hot-humid climate. This report covers a moderate-level retrofit and includes 2 years of pre-retrofit data to characterize the impact of improvements. The other home, covered in a separate report (Parker and Sherwin 2012), is a deep energy retrofit that has …

Flow And Heat Transfer In An L-Shaped Cooling Passage With Ribs And Pin Fins For The Trailing Edge Of A Gas-Turbine Vane And Blade, Irsha Ashok Pardeshi

Open Access Theses

Efficient and effective cooling of the trailing edges of gas-turbine vanes and blades is challenging because there is very little space to work with. In this study, CFD simulations based on steady RANS closed by the shear-stress transport turbulence model were performed to study the flow and heat transfer in an L-shaped duct for the trailing edge under two operating conditions. One operating condition, referred to as the laboratory condition, where experimental measurements were made, has a Reynolds number at the duct inlet of Re_D = 15,000, coolant inlet temperature of T_inlet = 300 K, wall temperature of …

Effect Of Cooling Rate On Oxidation Behaviour Of Microalloyed Steel, Xianglong Yu, Zhengyi Jiang, Jingwei Zhao, Dongbin Wei, Cunlong Zhou

Faculty of Engineering and Information Sciences - Papers: Part A

Oxidation characteristics of a microalloyed low carbon steel were investigated by a hot rolling mill combined with acceleration cooling system over the cooling rate range from 20 to 70°C/s. The effects of cooling rate after hot rolling on microstructure and phase composition of oxide scale were examined. The results showed that the increase of the cooling rate has a significant influence on the decrease of the grain size and surface roughness of oxide scale. A higher cooling rate promotes the formation of retain wustite and primary magnetite precipitation while suppression of eutectoid α-iron precipitates. This provides the possibility to enhance …

Work Hardening Behaviors Of A Low Carbon Nb-Microalloyed Si-Mn Quenching-Partitioning Steel With Different Cooling Styles After Partitioning, Jun Zhang, Hua Ding, Chao Wang, Jingwei Zhao, Ting Ding

Faculty of Engineering and Information Sciences - Papers: Part A

In this paper, the strain hardening behaviors of a low carbon Nb-microalloyed Si–Mn quenching–partitioning (Q–P) steel were investigated. The microstructures were analyzed by the scanning electron microscope (SEM) and transmission electron microscope (TEM). Mechanical tests were used to evaluate the room temperature tensile properties of the steel. The work hardening behaviors of the tested specimens were analyzed using the Hollomon approach. The results showed that a two-stage work hardening behavior was observed during deformation processes. In the first stage, for the quenched samples, martensite deforms plastically and the hardening exponent decreased. For the air-cooled samples, however, the carbide-free ferrite deforms …