The Clouds and the Earth's Radiant Energy System (CERES) is a program sponsored by the National Aeronautics and Space Administration (NASA) aimed at evaluating the global energy balance. Current scanning radiometers used for CERES consist of thin-film thermistor bolometers viewing the Earth through a Cassegrain telescope. The Thermal Radiation Group, a laboratory in the Department of Mechanical Engineering at Virginia Polytechnic Institute and State University, is currently studying a new sensor concept to replace the current bolometer: a thermopile thermal radiation detector. This next-generation detector would consist of a thermal sensor array made of thermocouple junction pairs, or thermopiles. The objective of the current research is to perform a thermal analysis of the thermopile. Numerical thermal models are particularly suited to solve problems for which temperature is the dominant mechanism of the operation of the device (through the thermoelectric effect), as well as for complex geometries composed of numerous different materials. Feasibility and design specifications are studied by developing a dynamic electrothermal model of the thermopile using the finite element method. A commercial finite element-modeling package, ALGOR, is used. / Master of Science

Magister Chirurgiae Dentium - MChD / Objectives: Temperature changes along an implant body have not been widely studied. The objectives of this in vitro study were (i) to establish if the temperature of the abutment influences the temperature of the implant surface, (ii) to establish the temperature transmission from abutment to implant body, and (iii) to establish for what abutment temperature the critical time/temperature threshold of 47oC for 1 minute at implant level is reached. Materials and method: Eight K-type thermocouples were attached to an abutment/implant configuration, mounted in a thermostatically controlled environment. The abutment was exposed to hot water. The temperature at each thermocouple along the implant was logged over a maximum period of 10 minutes using appropriate software. The test was repeated 200 times. A logistic regression model was used for the analysis of the time/temperature databases. Results: There was a positive correlation between the temperatures of the implant and its abutment, albeit with a time delay. Critical threshold values for bone necrosis were reached. The effective dose 50 was estimated at 62.3oC (95% confidence interval estimate): for an abutment temperature of 62.3oC there is a 50% chance that 47oC for 1 minute at implant level is reached. Conclusion: The results of this in vitro study support the hypothesis that abutment temperature is transmitted to a dental implant body. Results of in vitro studies should be interpreted with caution. However, clinicians should be aware of temperature changes along implants and the potential risk associated with this. / South Africa

ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Thermocouple measurements require “cold junction” compensation in order to obtain a correct reading. This compensation has traditionally been done with custom circuitry. In flight test applications where volume and power are at a premium (e.g. weapons flight test) it is desirable to have a more flexible solution that uses standard analog data acquisition channels already available as part of the encoder circuitry and performs compensation with remote software. This can be done via digital compensation, but certain measures must be taken to maintain accuracy and minimize noise. This paper describes some of these techniques and their performance tradeoffs.

The Veo+ projector is using a cooling system that consists of fan and blowers. This system is cooling the electronic components of the device and the lamp of the projector, however extracting a high noise. To lower this noise the rpm speeds (rotational speed) of the fan and blowers should be decreased. Thus, lowering the speed will result in higher temperature values in whole system (inside the device). While lowering the speed, the higher temperature values should be kept within the thermal design specifications of the electronic components. The purpose of this thesis work is to find an optimal solution with lower rpm speeds of the fan and blowers while keeping the temperatures of the various components of the device (touch temperature of the enclosure and electronic components) within the temperature design limits. Before testing the device to find the optimum state, the design limits of the device are determined. Then, by using the design of experiment methods like Taguchi, the optimum state for the device within the design specifications is obtained. Finally, additional tests are applied within the optimum state to demonstrate a fan algorithm as a final solution. While doing the experiments thermocouples are used for measuring the component temperatures.

The development of a simulation strategy and modelling algorithm with potential application to a variety of food process operations, particularly to thermal processing of canned foodstuffs has been undertaken. A review of published work identified previous efforts in the development of mathematical models for thennal process operations, including their limitations. The review showed that Finite Difference methods have found wide application in modelling conduction heating of canned foods. A similar model would be a useful numerical yardstick for validating any developments in this work. The great diversity of food handling operations have been grouped into a more manageable small number of classes. Such classification recognised that sets of related operations share common characteristics and functions which are the basis for the development of mathematical models for each class of operations. The strategy developed involved hierarchical decomposition of unit operations into assemblies of basic modules and mathematical modelling of these basics. A model of the operation can then be constructed simply by selecting and arranging the required basic units with due consideration to the boundary conditions of the physical problem. For transient operations with positional variation, these elementary modules have been termed "zones". The range of basic zones to model representative units have been identified. This hierarchical zone-model simulation has been demonstrated for heat transfer in a cylindrical container and for batch retort operation. The repeated use of the same unit modules for different operations makes this a flexible and robust strategy. The mathematics of zone-modelling has been developed for heat conduction in foodstuffs in cylindrical containers. To ensure accuracy, the numerical integration steps were rigorously monitored using mathematical procedures well-established for this purpose. The validity of the model has been tested against the analytical and implicit finite difference solutions. Generally, zone models agreed within 1 % of these standard yardsticks with the difference becoming negligible when sufficiently small integration steps or zone sizes were used. The effectiveness of zone-modelling as a simulation tool has been established using experimental data and the various sources of discrepancy between the model and experimental data accounted for. Thermocouple measurement errors have been found to have contributed most significantly to this discrepancy. Detailed analysis and modelling of thermocouple measurement errors has been carried out using zone-modelling to simulate the true experimental system which accounted for the presence of a thermocouple. The result has been an improved agreement between experiment and the zonemodel, and it also demonstrated the flexibility of the modelling technique. Further resuhs have shown that the discrepancy varied with thermocouple size and type. The contributions to error of temperature variability of, and of uncertainty in, thermophysical properties of the food were discussed. , The flexibility and robustness of zone-modelling have been further demonstrated using some practical situations including heat transfer to foodstuff in flexible packaging - such as sausage rolls, heat transfer in a food container with varying headspaces and the consequence of steam interruption during processing. Examples have been discussed of other transient processes that could similarly be modelled using this technique. The main achievements of this work include the application of hierarchical simulation and zonemodelling techniques to food processing and the development of a novel mathematical modelling technique which is more flexible than finite differences. Moreover, the applications of zonemodelling to the study of thermocouple errors, to the study of the consequences of steam interruption during thermal processing, and to heat transfer in foods in flexible containers, are developments of interest in food processing. It is concluded that the hierarchical simulation and zone modelling algorithm are robust and flexible techniques with potential applications in food process simulation .

The Navy is interested in comparing multi-thermocouple probes, tested in the field, with scanned laser absorption thermometry. This comparison aims to understand the effects of excess Carbon Monoxide (CO) and carbon (soot) resulting from rich nitromethane (CH3NO2) combustion events interacting with the outside air, as well as aluminum catalysts, on the temperature of the ensuing fireball. These interactions create mixing zones with varying gas temperature and composition. Currently, research at the UCF shock tube involves taking preliminary CO-scanned thermometry data with the goal of comparing thermocouple insert results in the future. The thermocouple insert is securely positioned within a specially designed end wall and protected by a heat shield. By comparing the temperature measurements obtained by one-dimensional shock relations with those obtained through scanned laser thermometry, based on CO characterization experiments conducted previously on the same shock tube, we aim to analyze temperature measurements and evaluate how the presence of the thermocouple insert affects the incident shockwave geometry, as well as the resulting reflected wave and temperature conditions. The goal is to observe any discrepancies in temperature measurements between the one-dimensional shock relations and the scanned laser method. This will enable researchers to assess the impact of the thermocouple insert in testing environments. Experiments were conducted using a mixture of 3% carbon monoxide (CO), 20% helium (He), and 77% argon (Ar), with an expected temperature range of 950 – 1950K, at pressures of 0.7 – 1 atmosphere (atm).

The measurement of temperature in hot gases plays an important role in many engineering applications, such as the efficiency and performance of an engine. As such, understanding the accuracy of these temperature measurements is also important. One of the common ways in which temperature is measured is through the use of total temperature probes. Previous research both at Virginia Tech and in outside studies has been performed to quantify the errors associated with total temperature probe measurements. This work has led to the development of low-order models which can be used to calculate the performance of a total temperature probe as a first-order estimate. These low-order models require knowledge of the heat transfer to the total temperature sensor in order to calculate the probe performance. However, the heat transfer to the sensor is a difficult quantity to calculate and has only been quantified over a set range of operating conditions for a single probe design. This research seeks to expand the range of applicability of the Virginia Tech low-order model by quantifying the heat transfer to the sensor of a total temperature probe over a range of probe geometries through the use of computational models. Key geometry parameters were altered to understand how altering these geometry features would impact the heat transfer to the sensor. In order to quantify the heat transfer to the sensor for varied probe geometries, a new method of characterizing the flow conditions about the sensor was also developed. By characterizing the flow conditions about the sensor, a better quantification of the heat transfer can be obtained. This thesis presents the correlation that was developed to quantify the changes in the flow about the sensor caused by varying the key geometry parameters. The flow conditions encompassed total temperatures from 294 K to 727 K at a Mach number of 0.4. The changes in the flow conditions about the sensor are then used to develop a heat transfer correlation to allow the heat transfer to the sensor to be calculated based off the changes in the flow conditions. The heat transfer to the sensor can then be substituted into the low-order model and used to calculate the performance of a total temperature probe. / Master of Science / The measurement of temperature in hot gases plays an important role in many engineering applications, such as the efficiency and performance of an engine. As such, understanding the accuracy of these temperature measurements is also important. One of the common ways in which temperature is measured is through the use of total temperature probes. Previous research has been performed to quantify the errors associated with total temperature probe measurements. This work has led to the development of low-order models which can be used to calculate probe errors. These low-order models require knowledge of the heat transfer to the total temperature sensor in order to calculate the probe errors. However, the heat transfer to the sensor is a difficult quantity to calculate and has only been quantified over a set range of flow conditions for a single probe design. This research seeks to quantify how the heat transfer to the sensor of a total temperature probe changes for different probe designs. Key geometry parameters were altered to understand how changing these geometry features would impact the heat transfer to the sensor. This thesis presents how the heat transfer to the total temperature sensor can be calculated over a range of different probe designs. The heat transfer to the sensor can then be substituted into the low-order model and used to calculate the performance of a total temperature probe.

Neste trabalho foram estudadas deposições químicas de ligas CuNixPy e foram fabricados termopares Cu/CuNixPy sobre superfícies de lâminas de silício. Inicialmente, as superfícies foram pré-ativadas em uma solução diluída de ácido fluorídrico contendo PdCl2. Em seguida, foi empregado um banho químico alcalino diluído em água deionizada contendo 15 g/l NiSO4.6H2O; 0,1 a 0,3 g/l CuSO4.5H2O; 15 g/l Na2HPO2.H2O e 60 g/l Na3C6H5O7.2H2O na temperatura de 80OC sendo que NH4OH foi adicionado até que o pH do banho atingisse o valor de 8,0. Verificamos que a concentração do sal de cobre na solução de deposição afeta substancialmente a quantidade de cobre nos depósitos de CuNixPy. As concentrações planares e as composições dos filmes depositados foram obtidas através da técnica de espectrometria de retroespalhamento de Rutherford (RBS) e a morfologia superficial foi caracterizada através da técnica de microscopia de força atômica (AFM). A solução: 15 g/l NiSO4.6H2O + 0,3 g/l CuSO4.5H2O + 15 g/l Na2HPO2.H2O + 60 g/l Na3C6H5O7.2H2O + NH4OH (pH 8.0) na temperatura de 80OC foi a escolhida na obtenção da liga CuNiP0,5 para a construção de termopares Cu/CuNiP0,5 os quais apresentaram potência termoelétrica de aproximadamente (866) V/oC semelhante aos valores típicos apresentados na literatura para Cu/CuNi. / In this work, it was studied chemical depositions of CuNixPy alloys and it was fabricated Cu/CuNixPy thermocouples onto silicon wafer surfaces. Initially, surfaces were pre-activated in a diluted hydrofluoric acid solution containing PdCl2. Following, it was used a de-ionizedwater- diluted alkaline chemical bath containing 15 g/l NiSO4.6H2O; 0,1-0,3 g/l CuSO4.5H2O; 15 g/l Na2HPO2.H2O and 60 g/l Na3C6H5O7.2H2O at temperature of 80OC where NH4OH was added until ph was 8.0. The concentration of copper salt in the deposition solution greatly affected the Cu content of the CuNixPy deposits. Areal concentration and composition were measured by Rutherford Backscattering Spectrometry (RBS) and surface morphology was characterized by Atomic Force Microscopy (AFM). The solution: 15 g/l NiSO4.6H2O; 0.3 g/l CuSO4.5H2O; 15 g/l Na2HPO2.H2O; 60 g/l Na3C6H5O7.2H2O; NH4OH (pH 8.0) at the temperature of 80OC was chosen to obtain the CuNiP0.5 alloy to fabricate Cu/CuNiP0.5 thermocouples with thermoelectric power of about (866) V/oC, which is similar to the typical values reported in literature for Cu/CuNi.

Neste trabalho foram estudadas deposições químicas de ligas CuNixPy e foram fabricados termopares Cu/CuNixPy sobre superfícies de lâminas de silício. Inicialmente, as superfícies foram pré-ativadas em uma solução diluída de ácido fluorídrico contendo PdCl2. Em seguida, foi empregado um banho químico alcalino diluído em água deionizada contendo 15 g/l NiSO4.6H2O; 0,1 a 0,3 g/l CuSO4.5H2O; 15 g/l Na2HPO2.H2O e 60 g/l Na3C6H5O7.2H2O na temperatura de 80OC sendo que NH4OH foi adicionado até que o pH do banho atingisse o valor de 8,0. Verificamos que a concentração do sal de cobre na solução de deposição afeta substancialmente a quantidade de cobre nos depósitos de CuNixPy. As concentrações planares e as composições dos filmes depositados foram obtidas através da técnica de espectrometria de retroespalhamento de Rutherford (RBS) e a morfologia superficial foi caracterizada através da técnica de microscopia de força atômica (AFM). A solução: 15 g/l NiSO4.6H2O + 0,3 g/l CuSO4.5H2O + 15 g/l Na2HPO2.H2O + 60 g/l Na3C6H5O7.2H2O + NH4OH (pH 8.0) na temperatura de 80OC foi a escolhida na obtenção da liga CuNiP0,5 para a construção de termopares Cu/CuNiP0,5 os quais apresentaram potência termoelétrica de aproximadamente (866) V/oC semelhante aos valores típicos apresentados na literatura para Cu/CuNi. / In this work, it was studied chemical depositions of CuNixPy alloys and it was fabricated Cu/CuNixPy thermocouples onto silicon wafer surfaces. Initially, surfaces were pre-activated in a diluted hydrofluoric acid solution containing PdCl2. Following, it was used a de-ionizedwater- diluted alkaline chemical bath containing 15 g/l NiSO4.6H2O; 0,1-0,3 g/l CuSO4.5H2O; 15 g/l Na2HPO2.H2O and 60 g/l Na3C6H5O7.2H2O at temperature of 80OC where NH4OH was added until ph was 8.0. The concentration of copper salt in the deposition solution greatly affected the Cu content of the CuNixPy deposits. Areal concentration and composition were measured by Rutherford Backscattering Spectrometry (RBS) and surface morphology was characterized by Atomic Force Microscopy (AFM). The solution: 15 g/l NiSO4.6H2O; 0.3 g/l CuSO4.5H2O; 15 g/l Na2HPO2.H2O; 60 g/l Na3C6H5O7.2H2O; NH4OH (pH 8.0) at the temperature of 80OC was chosen to obtain the CuNiP0.5 alloy to fabricate Cu/CuNiP0.5 thermocouples with thermoelectric power of about (866) V/oC, which is similar to the typical values reported in literature for Cu/CuNi.

Due to their small size and ectothermic biology, the heat production of insects and insect larvae is hard to quantify. However, knowing the amount of heat production, as well as ammonia production of insects may be beneficial for commercial production of valuable insect species. Black soldier fly larvae (BSFL) are of interest in the agricultural industry because they quickly consume organic waste and have high amounts of protein and fat in their bodies. It has been proposed that BSFL be used to manage livestock waste, while serving as a high-protein feed source for livestock animals. To efficiently rear BSFL, it is necessary to design rearing facilities, which maintain optimal conditions for the larvae. To design such a facility, it is necessary to know the amount of heat and ammonia that BSFL produce. A gradient calorimeter was used to measure the heat and ammonia production rates of black soldier fly larvae. The study determined that BSFL heat production changes significantly with the age and weight of the larvae. Aggregations produce the most total heat when larvae are older and larger. The study also found that larvae produce less heat per individual and per gram of body weight as they grow. Larvae also produce significantly different amounts of heat depending on the size of the groups they are in, and do not produce consistent amounts of heat per individual or per gram of body weight, even if maintained at a consistent population density. Larvae in group sizes of 100, 300, and 500 produced an average and standard deviation of 0.00107±0.000295, 0.00067±0.00014, and 0.00049±0.00020 W/larva, respectively. Likewise, larvae in groups of 100, 300 and 500 produced an average of 0.01826±0.00010, 0.01023±0.00565, and 0.00575±0.00371 W/g, respectively. The differences in heat produced per individual and per gram is troublesome when trying to estimate a total heat production for large populations. The largest heat production rate observed in this study was 0.407 W, and was produced by a group of 500 BSFL. Frass analysis indicated that between 4.80 and 7.79 lbs of ammoniacal-nitrogen is emitted for every ton of frass produced. These data could be used to estimate the total heat and ammonia produced from a larger population of BSFL being reared inside a closed facility, allowing engineers to design HVAC systems to keep the larvae at their optimal growing condition year-round. Placing BSFL rearing accommodations at livestock facilities could be beneficial to livestock, poultry, and fishery producers, because BSFL can be used to dispose of animal wastes and are also a good source of protein-rich animal feed.