著者

菊地 謙次 寺田 信幸 望月 修

出版者

公益社団法人 日本生体医工学会

雑誌

生体医工学 (ISSN:1347443X)

巻号頁・発行日

vol.46, no.2, pp.232-237, 2008-04-10 (Released:2008-10-06)

参考文献数

4

被引用文献数

1

---

Many researches and developments have tried to realize a μTAS in several fields, but it has not been realized yet because of a scale effect in the course of miniaturization. It is difficult to make an enough volume of flow in a micro tube. This is a bottleneck of realizing the μTAS. We have tried to apply a unique mechanism of insects to the μTAS devises. In this paper, we focused on a blood-sucking mechanism of a mosquito that can obtain blood at the rate of approximately 1.0 μl/min. To understand the structure of their pumps, we made a mosquito into many slices, and anatomized under a microscope; we also let mosquitoes feed on human blood on a glass plate. We found the following results: 1) a manner of blood sucking, 2) a power density of the pump system by an analysis of flowing red blood cells at a tip of proboscis of mosquito. We have succeeded to reveal the blood-sucking mechanism of the mosquitoes, which can be applied to micro fluid devices.

著者

菊地 謙次 今野 友博 市川 誠司 窪田 佳寛 望月 修

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集B編 (ISSN:18848346)

巻号頁・発行日

vol.79, no.798, pp.151-163, 2013 (Released:2013-02-25)

参考文献数

29

被引用文献数

2

---

The purpose of this study is to know differences between steady and unsteady drag coefficients of a sphere. Though we often have to estimate unsteady drag-forces acting on a moving obstacle, we are obliged to use the well-known steady drag coefficient for the first estimation because of lack of information about effects of unsteadiness on the drag coefficient. The usual way to take account of unsteadiness is an added mass. However, its application is restricted within the simple shape of an obstacle. We propose a way based on the equation of motion to obtain the unsteady drag coefficient. To confirm validity of the way, we measured and analyzed the motion of the falling sphere in water by using a high-speed camera and a motion capture method. The drag coefficients as a function of time were obtained by substituting measured values of velocity and acceleration into the equation of motion. The drag coefficient was 0.52 when the sphere attains the terminal velocity, being quite large at the beginning of motion. Comparing with the values obtained by the other previous studies, our result is reasonable.