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I address the geometric problem of the pendulum-like swinging of towed birds for AEM platforms. I establish a link between actual observed bird swing and its effect on survey data for two different systems and explain the link by a model that compares actual survey data to the calculated mutual inductance coupling of a dipole pair over an infinitely conductive half space, which pair is permitted arbitrary pitch, roll and altitude changes. I develop a non-linear filter that removes bird swing effects from survey data which successfully corrected data from 3 different AEM surveys. Calibration of several different time domain AEM systems is attempted using an accurately laid out and surveyed, closed, multi-turn loop of known resistance and self-inductance that is placed on - but insulated from - resistive ground. I derive a rigourous mathematical model that predicts airborne receiver's response to the coupling to the transmitter current waveform and total system geometry. The method was proven to be successful over resistive ground, with significant system problems identified such as: altimetry error, spatial averaging of data during postprocessing, error in the predicted horizontal position of the AEM platform, receiver windowing and timing errors and bird swing. I show that, although we can calibrate a time domain AEM system for a single flyover, it is impossible to calibrate an AEM system for geometry. As an intermediate step in the calibration process, I show that by monitoring the current induced in the ground loop we can obtain the waveform of the AEM transmitter current throu gh deconvolution in the Fourier domain. Simple and cost effective methods for the improvement of quantitative AEM data are presented in this thesis. However, until the geometry problem of AEM platforms is solved, full system calibration will not be obtained and filters will need to be applied to the data. I recommend the use of: GPS antennas mounted on all towed birds, able to be post-processed for accurate position recovery, reliable bird-mounted scanning altimeters that do not rely on range-finding technology but instead employ a shortest path algorithm, pitch and roll sensors mounted on the trailed bird and the measurement of airspeed of both the towed bird and the aircraft during surveys.

Horizontal ground loop heat exchangers (GLHE) are widely used in many countries around the world as a heat source/sink for building conditioning systems. In Canada, these systems are most common in residential buildings that do not have access to the natural gas grid or in commercial structures where the heating and cooling loads are well balanced. These horizontal systems are often preferred over vertical systems because of the expense of drilling boreholes for the vertical systems. Current practice when sizing GLHEs is to add a considerable margin of safety. A margin of safety is required because of our poor understanding of in situ GLHE performance. One aspect of this uncertianty is in how these systems interact with heterogeneous soils. To investigate the impact of soil thermal property heterogeneity on GLHE performance, a specialized finite element model was created. This code avoided some of the common, non-physical assumptions made by many horizontal GLHE models by including a representation of the complete geometry of the soil continuum and pipe network. This model was evaluated against a 400 day observation period at a field site in Elora, Ontario and its estimates were found to be capable of reaching a reasonable agreement with observations. Simulations were performed on various heterogeneous conductivity fields created with GSLIB to evaluate the impact of structural heterogeneity. Through a rigorous set of experiments, heterogeneity was found to have little effect on the overall performance of horizontal ground loops over a wide range of soil types and system configurations. Other variables, such as uncertainty of the mean soil thermal conductivity, were shown to have much more impact on the uncertainty of performance than heterogeneity. The negative impact of heterogeneity was shown to be further minimized by: maintaining a 50 cm spacing between pipes in trenches; favouring multiple trenches over a single, extremely long trench; and/or using trenches greater than 1 m deep to avoid surface effects.

Ground source heat pumps (GSHP) have the ability to significantly reduce the energy required to heat and cool buildings. Historically, deployment of GSHP's in the cooling-dominated Texas and Southwest region has been significantly less than in other regions of the United States. The long term technical and economic viability of GSHPs in arid regions such as Texas has been questioned due to failures of ground loop heat pump systems by early adopters. A proposed solution is to include a supplemental heat rejection (SHR) device to help offset the unbalanced ground loads. An integrated building load-ground source heat pump model is developed in this thesis and is designed to be a test bed for potential SHR devices. The model consists of discrete component models that can be mixed and matched to represent various types of buildings and ground source heat pumps. One of the unique features of the integrated model is the use of the Simulink/Matlab environment. This environment allows the user to develop component models that take advantage of the built-in functionality of Matlab and Simulink. Another unique feature is the full coupling of the building load, heat pump, and ground loop at every time step. The building load, heat pump, and ground loop models were chosen to allow for short time step simulations, which allows for a range of dynamic response times to be modeled and for different heat pump/SHR control methods to be explored. The integrated model can be used on any computer that has the Matlab and Simulink software. The building load model used, called HAMBASE, can model both residential and commercial buildings. HAMBASE was validated using the ASHRAE 140-2007 standard. The heat pump model uses readily available data provided by GSHP manufacturers to accurately model operation across a wide range of input conditions. The vertical borehole ground loop model, developed at Oklahoma State University, is based on Eskillson's g-function model, but included a one-dimensional numerical model to calculate the short term thermal response of the borehole and ground. The ground loop model utilizes GLHEPRO, a ground loop sizing and simulation tool, to create the required parameter files. Using the integrated building load-ground source heat pump model, a model of a single family house with a ground source heat pump was developed. The house model was validated by the results from eQuest and GELHPRO. A series of sensitivity studies were completed to determine dominant factors affecting the use of GSHPs in Texas and the Southwest regions of the United States. The results show that the life of a vertical borehole can be significantly extended/cut short if the ground parameters are properly/not properly designed prior to ground loop sizing. / text

Horizontal ground loop heat exchangers (GLHE) are widely used in many countries around the world as a heat source/sink for building conditioning systems. In Canada, these systems are most common in residential buildings that do not have access to the natural gas grid or in commercial structures where the heating and cooling loads are well balanced. These horizontal systems are often preferred over vertical systems because of the expense of drilling boreholes for the vertical systems. Current practice when sizing GLHEs is to add a considerable margin of safety. A margin of safety is required because of our poor understanding of in situ GLHE performance. One aspect of this uncertianty is in how these systems interact with heterogeneous soils. To investigate the impact of soil thermal property heterogeneity on GLHE performance, a specialized finite element model was created. This code avoided some of the common, non-physical assumptions made by many horizontal GLHE models by including a representation of the complete geometry of the soil continuum and pipe network. This model was evaluated against a 400 day observation period at a field site in Elora, Ontario and its estimates were found to be capable of reaching a reasonable agreement with observations. Simulations were performed on various heterogeneous conductivity fields created with GSLIB to evaluate the impact of structural heterogeneity. Through a rigorous set of experiments, heterogeneity was found to have little effect on the overall performance of horizontal ground loops over a wide range of soil types and system configurations. Other variables, such as uncertainty of the mean soil thermal conductivity, were shown to have much more impact on the uncertainty of performance than heterogeneity. The negative impact of heterogeneity was shown to be further minimized by: maintaining a 50 cm spacing between pipes in trenches; favouring multiple trenches over a single, extremely long trench; and/or using trenches greater than 1 m deep to avoid surface effects.

A data acquisition system (DAQ) was designed based on the use of a STM32 microcontroller. Its purpose is to provide a transparent and low-cost alternative to commercially available DAQs, providing educators a means to teach students about the process through which data are collected as well as the uses of collected data. The DAQ was designed to collect data from rotating machinery spinning at a speed up to 10,000 RPM and send this data to a computer through a USB 2.0 full-speed connection. Multitasking code was written for the DAQ to allow for data to be simultaneously collected and transferred over USB. Additionally, a console application was created to control the DAQ and read data, and MATLAB code written to analyze the data. The DAQ was compared against a custom assembled National Instruments CompactDAQ system. Using a Bentley-Nevada RK 4 Rotor Kit, data was simultaneously collected using both DAQs. Analysis of this data shows the capabilities and limitations of the low cost DAQ compared to the custom CompactDAQ.

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