Study on Distributed High Specific Power Micro-engines

1.微型斯特林发动机的设计与制造微型斯特林发动机是一种微型斯特林发动机，其机身长度或高度不超过几厘米。研究了建立设计概念和实际生产微执行器所采取的步骤。通过几何尺度分析和计算机仿真，研究了发动机尺寸减小时设计参数的变化。这种分析和模拟使微型斯特林发动机能够制造出具有大约50毫升活塞后掠量的微型发动机。在100K温差下，输出功率约为10 mW，比功率约为1W/kg2。光驱动微执行器我们设计并制作了光驱动微执行器，作为分布式高比功率执行器的阵列。光驱动微执行器是一种具有由加热的工作流体(氟利昂113)驱动的膜的微电池。热量由半导体激光器通过光纤提供。薄膜为0.8 mm方形，0.8 mm厚，由NiCrSi制成。在50 mW的激光功率下，膜的最大位移为35 mm，在5 Hz的脉动激光输入下，微细胞可以响应。设计并制造了一种激光驱动的微机械流体泵。该泵由微电池阵列组成。它们被一块有18毫米间隙的薄玻璃板覆盖，形成了一个流动通道。用气动泵代替激光驱动的实验结果合理，但由于工作气体冷却延迟，光驱动的实验结果并不令人满意。

1. Design of micro Stirling engineThe micro Stirling engine, a miniaturized Stirling engine the length, or height of whose body measured no more than several centimeters, was designed and fabricated. The steps taken both to establish the design concept and actually to produce a microactuator were investigated. Geometrical scale analysis and computer simulation are used to investigate how the design parameters change when the engine size was reduced. This analysis and simulation enable a micro Stirling engine with an approximately 50 ml piston swept volume to be produced. The output power is approximately 10mW at 100K temperature difference, and specific power is about 1W/kg.2. Light driven micro actuatorWe designed and fabricated light driven micro actuators which was intended to use as array of distributed high specific power actuators. The light driven micro actuator is a microcell which has a membrane actuated by heated working fluid(Freon 113). Heat is supplied by semiconductor laser through an optical fiber. The membrane is 0.8 mm square and 0.8mm thickness, and made of NICrSI. The maximum displacement of the membrane measured 35mm at 50mW laser power, and the microcell could respond at 5Hz pulsative laser input.3. Application of an array of the actuatorsA laser light driven micromechanical pump for fluid has been designed and fabricated. The pump consists of an array of the microcells. These are covered by a thin glass plate with a 18 mm gap which makes a flow channel. The experiment driven by pneumatic pump instead of laser light showed reasonable pump performance, but the one driven by light was not satisfied results because of delay of working gas cooling.A guide mechanism of a medical catheter using array of the microcell was also investigated.