STTR Phase I: Actively Controlled Self-Aspirating Microelectromechanical (MEMS) Fuel Atomizer

这项小型企业技术转移（STTR）第一阶段研究项目将开发一种用于定时向化油器发动机喷射燃油的自吸气微机电（MEMS）雾化器。液体燃料化油器最常用于小型汽油发动机仪表，它将燃料与流入发动机的空气喷射并混合。然而，该系统不能定时喷射，因此发动机遭受相对较差的燃油经济性和高排放水平。不幸的是，小型发动机排放了大量的HC、CO、NOx和颗粒物，这些物质会形成烟雾，并含有有毒化合物，如苯、甲苯、甲醛、乙醛和丙烯醛。由于大量的污染，美国环保署对这些发动机制定了排放法规，现有技术将无法以经济有效的方式满足这一要求。提出的工作将开发用于定时喷射的低成本MEMS燃油雾化器。这个一期项目将确定这项新技术的可行性，并提出其制造的设计。低成本的小型发动机使大量的休闲车辆和家用设备成为可能；仅发动机一项，美国市场的年销售额就高达2000万美元。这些发动机用简单的化油器加油，既可靠又便宜。不幸的是，这些发动机的排放量太高，无法满足美国环保署将在未来两年内实施的规定。降低排放的燃料控制技术必须像化油器一样便宜和耐用，否则它们不会得到广泛应用。主动控制和自吸式MEMS燃料雾化器可以在低成本的集成电路微加工设备上大量建造。因此，与竞争技术相比，所提出的雾化器将以更低的成本提高燃油经济性和减少排放。

This Small Business Technology Transfer (STTR) Phase I research project will develop a self-aspirating microelectromechanical (MEMS) atomizer for timed fuel injection into carbureted engines. The liquid fueled carburetor most commonly used in small gasoline fueled engines meters, injects and mixes the fuel with the air flowing to the engine. However, the system cannot time the injection, so the engines suffer from relatively poor fuel economy and high emission levels. Unfortunately, small engines account for significant amounts of HC, CO, NOx, and Particulate Matter emissions, which form smog and contain toxic compounds such as benzene, toluene, formaldehyde, acetaldehyde, and acrolein. Due to this significant amount of pollution, the EPA has mandated emissions regulations for these engines, which existing technology will be unable to meet in a cost effective manner. The proposed work will develop low-cost MEMS fuel atomizers for timed injection. This Phase I project will determine the feasibility of this new technology and proposed a design for its manufacture.Low-cost small engines have enabled a large number of recreational vehicles and equipment for home use; the U.S. market is about $20M per annum for the engines alone. These engines are fueled with simple carburetors, which are reliable and cost little. Unfortunately, the emissions from these engines are too high to meet EPA regulations that will be in place in the next two years. Fuel control technologies to lower the emissions must still be inexpensive and robust like the carburetors or they will not see widespread use. Actively controlled and self-aspirating MEMS fuel atomizers to be developed under this effort can be built in large numbers with low-cost IC microfabrication facilities. Therefore, the proposed atomizers will improve fuel economy and reduce emissions at much lower cost than the competing technologies.