A proliferation of choices available to consumers as they select a major cooking appliance necessitated the development of a Buyer’s Guide which will provide consumers with generic information by which they can compare range cooktops and microwave ovens. The microwave oven is included because it is often used in the place of a cooktop. The Buyer’s Guide for Range Cooktops and Microwave Ovens as an information resource is designed to be used by consumers to assist in making an informed purchase decision. The study was conducted in three phases: 1) identification of items included in the Buyer’s Guide; 2) establishment of test procedures; and 3) focus panel evaluation of the Buyer’s Guide. Phase 1 - Eleven items considered to be important in making purchase decisions were identified by members of the Virginia Retail Merchants Association and by Virginia home economics Extension agents. Items rated as important for inclusion were: purchase price, maintenance, life expectancy, operating costs, energy use, speed of heating, evenness of heating, heat retention, heat recovery, ease of cleaning, and ease of use. Phase 2 - Using standardized test procedures, data were obtained for the radiant coil electric smoothtop to allow the comparison of items found on the Buyer’s Guide with other types of range cooktops (conventional electric coil, gas burner, induction cooktop, smoothtop resistance coil, solid element) and the microwave oven. Phase 3 - Four focus panels were conducted to evaluate the Buyer’s Guide for Range Cooktops and Microwave Ovens for clarity of content, practicality of format, and its usefulness to consumers. The 26 focus panel participants recommended changes which were incorporated into the Buyer’s Guide for Cooktops and Microwave Ovens. They indicated a belief that the Buyer’s Guide would be useful for consumers seeking generic information by which to compare major cooking appliances. Further research is needed to evaluate the Buyer’s Guide for Range Cooktops and Microwave Ovens for its usefulness to consumers in the selection of a cooking appliance in the marketplace. / Ph. D.

Approximately 3 billion people in developing countries rely on solid fuels for their cooking, heating and lighting needs (Smith 2000). Household air pollution (HAP) from the incomplete combustion of these fuels constitutes the fourth leading risk factor for death and morbidity worldwide, and the number one risk factor for disease burden in some developing nations, including Ghana (Lim et al. 2013; Institute for Health Metrics and Evaluation 2016). While research shows biomass fuel combustion presents a significant global health and environmental burden, no regional, national or global policies have been enacted to reduce fine particulate matter (PM2.5) and black carbon (BC) emissions from cooking with biomass fuels. More data on personal exposures to particulate matter and BC from cooking with biomass are needed across geographic areas to assess whether exposure is mediated by (cultural) cooking customs, practices and behaviors. These data are critical in informing improved cookstove design as well as policies aimed at reducing harmful emissions and exposures from biomass smoke. The overall objective of this proposal is to examine personal exposures to cooking and non-cooking sources of HAP, characterize the elemental composition of the fine particulate matter across two common biomass fuels (charcoal and wood), and assess acute respiratory symptoms in pregnant women cooking with biomass fuels in rural Ghana. Through aerosol monitoring of PM2.5, our goal is to identify and apportion sources of personal exposures borne by cooks in rural Ghana, in order to inform mitigation policies and intervention design to alleviate health burden associated with cooking with biomass fuels. Specifically, in Aim 1 we propose to measure personal exposures and kitchen air concentrations of PM2.5 and BC across cooking locations, (i.e. enclosed, semi-enclosed, outdoor) and assess cooking characteristics (e.g. fuel, kitchen type, ethnicity) as possible determinants of exposure. In Aim 2, we will characterize the elemental composition of personal and kitchen air samples across fuel and kitchen types. These two aims will allow us to assess cooking and non-cooking sources of personal HAP exposure based on air monitoring data, composition of the filters, and survey-based cooking characteristics/demographics. In Aim 3, we propose to characterize the prevalence of adult respiratory symptoms in 1183 pregnant women in the region, and assess associations between personal exposure, measured by personal carbon monoxide (CO), and other cooking and non-cooking determinants of personal exposure, including fuel type, years cooked, kerosene lamp, mosquito coils, and charcoal production.

Competitive global markets are increasing the commercial pressure on manufacturing companies to develop better products in less time. To meet these demands, the appliance manufacturer, Fisher & Paykel, has considered the use of computer simulation of fluid flows to assist in product design. This technology, known as Computational Fluid Dynamics (CFD), has the potential to provide rewarding insight into the behaviour of designs involving fluids. However, the investment in CFD is not without risk. This thesis investigates the use of CFD in oven design expressly to evaluate the numerical accuracy and suitability of CFD in the context of oven product development. CFD was applied to four cases related to oven design, along with detailed experimental investigations, and resulted in a number of relevant findings. In a study of an impinging jet, the SST turbulence model was found to produce better results than the k-ε turbulence model. Measurements indicated that the flow was unsteady, but CFD struggled to reproduce this behaviour. The synergy between experimental and numerical techniques was highlighted in the simulation of a two-pane oven door, and resulted in temperatures on outer surface of the door predicted by CFD to within 2% of measured values. In the third study, a CFD simulation of a tangential fan failed to deliver acceptable steady-state results, however a transient simulation showed promise. The final case examined the flows through the door and cooling circuit of the Titan oven. Velocities predicted by CFD compared well against measurements in some regions, such as the potential core of the jet at the outlet vent, but other regions, such as entrained air, were poor. Temperatures were predicted to within an average of 2% of measured values. It is found that limited accuracy does not necessarily prevent CFD from delivering engineering value to the product development process. The engineering value delivered by CFD is instead more likely to be limited by the abilities of the user. Incompatibilities between CFD and the product development process can reduce the potential value of CFD but the effects can be minimised by appropriate management action. The benefits of CFD are therefore found to be sufficient to merit its use in the product development process, provided its integration into the organisation is managed effectively and the tool is used with discernment. Recommendations for achieving this are provided.

Thesis (M.A.)--Memorial University of Newfoundland, 2005. / Bibliography: leaves 277-290.

Typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1988. / Bibliography: leaves 520-551. / Photocopy. / Microfilm. / xxi, 551 leaves ill. 29 cm

Mémoire (M.Sc.A.)-- Université du Québec à Chicoutimi, 1988. / Document électronique également accessible en format PDF. CaQCU

Thesis (M.S.) -- Mississippi State University. Department of Mechanical Engineering. / Title from title screen. Includes bibliographical references.

M.S.

Residential coal stoves emit various pollutants such as CO, NO_x, SO_x, and smoke. The emissions can be reduced by varying the burning conditions in the stove. This investigation studied the effect of various burning conditions on the emissions from a two-stage lump coal combustor burning Wyoming bituminous coal. The parameters that were varied include primary air mass flow rate, secondary air mass flow rate, secondary air temperature, secondary air inlet velocity, and secondary air swirl. Each parameter was varied independently to attempt to isolate its effect on emissions. In addition, radial and axial probe sampling was conducted in the combustor's secondary combustion zone to determine the CO concentrations. A chemical kinetic model of CO oxidation was formulated and compared to the measured CO concentrations. A wide range of emission factors can be achieved for the various pollutants by varying the burning conditions. The CO, NO_x, SO_x, and smoke emission factors range from 7.0 to 159, 0.67 to 3.1, 0.98 to 2.0, and 0.16 to 3.7 g/kg respectively. The emissions tests appear to be reasonably repeatable with emission factors and coal burning rates agreeing within 15% in most cases. The various tests indicate that increasing the primary zone equivalence ratio decreases the CO emission factor. The smoke emissions from the test combustor are quite low compared to those from typical commercial coal stoves. The amount of swirl has a large effect on mixing in the secondary combustion zone, and highly stratified flows are created by certain burning conditions. The CO oxidation model does not correlate well with the experimental results since possible CO formation from hydrocarbons, and stratified flow effects are not considered. / Master of Science

The emissions, efficiency, and combustion chamber conditions of the Rayburn Prince 76, a clean-burning, hand-fired coal heater developed by the British have been studied. It was desired to determine if the downdraft design of the Prince would lead to low emissions when operated on American coals. Temperature and species concentrations were measured in the unit's secondary combustion chamber. Temperatures and gas residence times in the secondary combustion chamber were found to range from 440 to 1040°C and 15 to 40 ms, respectively. Little soot and volatile oxidation probably occurred in the chamber, due to the relatively low temperatures and short residence times. The emissions and efficiency of the heater were determined for operation on two bituminous coals at both high and low firing rates. The CO, NO_x, SO_x, and smoke emission factors were found to range from 38 to 120 g/kg, 1.2 to 5.8 g/kg, 3.3 to 5.4 g/kg, and 2.3 to 16 g/kg, respectively. The smoke emission factors for the Prince were found to be up to six times lower than those found using identical coals in updraft stoves. The overall efficiency of the unit was determined to range from 54 to 60%. The sensible energy losses were found to represent the majority of the total energy losses. / M.S.