Much analysis has been performed on the application of thermoelectrics in automobiles, but the low efficiency of the materials has so far limited their use. As a result, little has been done in the physical design of how to most efficiently utilize thermoelectrics in a vehicle's energy system. However, much progress has been and continues to be made in the field of thermoelectric materials. Developments in the areas of nanostructured materials have produced materials with double the efficiency of current commercially available materials. This, coupled with a growing need for the reduced consumption of fossil fuels and production of greenhouse gases, has generated renewed interest in the application of thermoelectrics in automotive systems. Hybrid-electric vehicle (HEV) designs have provided significant improvements in fuel efficiency and continue to evolve. This modified energy management strategy introduces new components and energy distributions which force traditional designs to be reconsidered. For example, the temperature and quantity of thermal energy transferred through the exhaust and radiator are lowered. Also, the IC engine may not be run continuously, creating difficulties in maintaining temperature in the catalytic converter, powering belt-driven accessories, and regulating cabin temperature. This contributes to an increased demand for electrical energy. Finally, the power electronics are typically liquid cooled (order of 60-65 °C) and the high voltage battery packs must be kept cool (typically below 45 °C) to maximize their life. A detailed computer model which captures the details of the energy transfers in HEV's, including thermal loads will be used to assess the unique thermal requirements of hybrid vehicles under average engine loads. Based on these requirements, specific thermal energy management strategies will be proposed. These modified systems will be added to the computer model in order to evaluate their potential using currently available thermoelectrics materials. Finally, the preferred thermal energy management system will be selected as the basis for future design optimization.
Opportunities for Thermoelectric Energy Conversion in Hybrid Vehicles
MARANO, VINCENZO;
2006-01-01
Abstract
Much analysis has been performed on the application of thermoelectrics in automobiles, but the low efficiency of the materials has so far limited their use. As a result, little has been done in the physical design of how to most efficiently utilize thermoelectrics in a vehicle's energy system. However, much progress has been and continues to be made in the field of thermoelectric materials. Developments in the areas of nanostructured materials have produced materials with double the efficiency of current commercially available materials. This, coupled with a growing need for the reduced consumption of fossil fuels and production of greenhouse gases, has generated renewed interest in the application of thermoelectrics in automotive systems. Hybrid-electric vehicle (HEV) designs have provided significant improvements in fuel efficiency and continue to evolve. This modified energy management strategy introduces new components and energy distributions which force traditional designs to be reconsidered. For example, the temperature and quantity of thermal energy transferred through the exhaust and radiator are lowered. Also, the IC engine may not be run continuously, creating difficulties in maintaining temperature in the catalytic converter, powering belt-driven accessories, and regulating cabin temperature. This contributes to an increased demand for electrical energy. Finally, the power electronics are typically liquid cooled (order of 60-65 °C) and the high voltage battery packs must be kept cool (typically below 45 °C) to maximize their life. A detailed computer model which captures the details of the energy transfers in HEV's, including thermal loads will be used to assess the unique thermal requirements of hybrid vehicles under average engine loads. Based on these requirements, specific thermal energy management strategies will be proposed. These modified systems will be added to the computer model in order to evaluate their potential using currently available thermoelectrics materials. Finally, the preferred thermal energy management system will be selected as the basis for future design optimization.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
