【論文特集】混相流研究の進展
超小型蒸気インジェクターの熱流動挙動と作動境界条件
2020 年 34 巻 1 号 p. 36-45
詳細
2020 年 34 巻 1 号 p. 36-45
A Steam Injector (SI) has capability to be applied to heat pump systems and to have downsized them. A SI works as passive jet pump and heat exchanger without external power sources. It has high heat-transfer performance due to direct contact condensation between steam flow and subcooled water jet. The objective of the present study is to clarify thermal hydraulics characteristics and operating criteria for an Ultra-Micro Steam Injector. To this end, SI with throat diameter of 2.0 mm was designed and investigated experimentally. Visualization of internal flow behavior and measurement of pressure and temperature were conducted. As a result, we confirmed that the formation of the water jet, the stop of drainage from the drain port and the increase of discharge pressure. The internal flow patterns were classified into four types and considering the energy balance of water and steam. One of the operating criteria was clarified that water could completely condense the steam. The discharge pressure was increased up to 2 times at maximum. There is possibility the operating criteria can be predicted from the position where the flow behavior changes.
