국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	An Experiment on Losses in a Three-Port Wave Rotor
저자	Jack Wilson
Keyword	Wave rotor; Losses
URL	http://gltrs.grc.nasa.gov/reports/1997/CR-198508.pdf
보고서번호	NASA CR-198508
발행년도	1997
출처	NASA Glenn Research Center
ABSTRACT	Wave rotors used in a gas turbine topping cycle, offer a potential route to higher specific power and lower specific fuel consumption. In order to exploit this potential properly, it is necessary to have some realistic means of calculating wave rotor performance, taking losses into account, so that wave rotors can be designed for good performance. This, in turn, requires a knowledge of the loss mechanisms. The experiment reported here was designed as a statistical experiment to identify the losses due to finite passage opening time, boundary layers, and leakage. On analyzing the data, incidence loss was also determined to be an important loss. For simplicity, the experiment used a three-port, flow divider, wave cycle, but the results are applicable to other cycles. A 12-in.-diameter rotor was used with two different lengths, 9 and 18 in., and two different passage widths, 0.25 and 0.54 in., in order to vary the boundary layer thicknesses and the opening time. To vary leakage, moveable end walls were provided so that the rotor to end-wall gap could be adjusted. The experiment is described and the results are presented together with a parametric fit to the data. The fit shows that there will be an optimum passage width for a given wave rotor since, as the passage width increases, boundary layer losses decrease, but opening-time losses increase and vice-versa. Leakage losses can be made small at reasonable gap sizes. Inlet ports should be designed to minimize incidence losses.