Experimental investigation on aerospike nozzle in different structures and working conditions

Author(s):  
Yu Liu ◽  
Guozhou Zhang ◽  
Wuye Dai ◽  
Bin Ma ◽  
Xianchen Cheng ◽  
...  
Author(s):  
Jingming Dong ◽  
Qiuyu Hu ◽  
Yuxin Xia ◽  
He Song ◽  
Hongbin Ma ◽  
...  

Abstract This paper presents an experimental investigation of a miniature ejector using water as the working fluid. The investigated ejector cooling system can utilize the thermal energy to be removed to power the cooling system and maintain the temperature of an electronic component below ambient temperature. The effects of working conditions, nozzle exit position (NXP), and area ratio on the coefficient of performance (COP) of ejector performance were investigated. Experimental results show that the miniature ejector can function well when the temperature in the high-temperature evaporator (HTE) ranges from 55 °C to 70 °C and can achieve a COP (coefficient of performance) of 0.66. With an increase of the NXP, the COP decreases, while the critical condensing pressure first increases and then decreases. As the area ratio of the miniature ejector increases, the COP increases, and the critical condensing pressure decreases.


Author(s):  
Wojciech Litwin

Water lubricated bearings are often installed on new and modernized ships. The main reasons are: unit simplicity, no danger of pollution and low price. One of the main problems connected with this the bearings of this kind is defining maximum hydrodynamic film capacity. Due to very thin hydrodynamic film and significant bearing bush deformation, the EHL model should be used for calculations. Experimental research conducted in the past was carried out on a single bearing test rig [1, 2, 3]. Unfortunately that test rig has some disadvantages. Its flexible support gives possibility of shaft misalignment for instance in case of asymmetric hydrodynamic pressure film in the bearing. The new test rig, presented in this paper gives wide research possibilities and working conditions are very similar to those on a real ship.


2006 ◽  
Vol 26 (10) ◽  
pp. 97-104
Author(s):  
Mashio TANIGUCHI ◽  
Hideo MORI ◽  
Ryutaro NISHIHIRA ◽  
Tomohide NIIMI

Author(s):  
Daniele Massini ◽  
Bruno Facchini ◽  
Mirko Micio ◽  
Riccardo Da Soghe

A rotating test rig, reproducing a rotor-stator cavity with an axial admission system, has been exploited for an experimental investigation on the internal flow field and its effect on heat transfer on the stator side. Working conditions were varied in a wide range of rotating velocities and superposed mass flow rates. 2D PIV flow measurements were performed in order to obtain a radial distribution of the tangential velocity, results were used to validate numerical simulations aimed at understanding the admission system effect on the swirl distribution. Heat transfer coefficient distribution along the stator disk has been evaluated performing a steady state technique exploiting Thermo-chromic Liquid Crystals (TLC). Tests have been performed varying the superposed mass flow rate up to reaching the condition of cavity completely sealed, further increase of the mass flow rate showed to reduce the effect of the rotation. Working conditions were set in order to investigate cases missing in open literature, however few tests performed in similarity with other researches provided comparable results.


2004 ◽  
Author(s):  
Takashi Suzuki ◽  
Yasufumi Oguri ◽  
Keisuke Uchida ◽  
Masatake Yoshida

The objective of this paper is to find experimentally the suitable working conditions of a pressure wave supercharger (PWS) for SI engine. A belt-driven CVT was installed in order to drive the rotor of PWS to the appropriate speed regardless of engine speed. The maximum BMEP was achieved by changing speed of the PWS rotor at constant engine speed and throttle open ratio. From the experiment, the appropriate rotor speeds which led to maximum BMEP at every engine speed and throttle open ratio were achieved. The results showed that two power peaks existed during the range of the tested rotor speed. Since the drop in BMEP between these two power peaks was relatively small, the rotor speed range between these points was defined as effective rotor speed. At engine speed of 2000–4000rpm, the effective rotor speed was found at the engine-rotor ratio of 2.5. In addition, the maximum compression efficiency of PWS was 75% at engine speed of 3000rpm and the exhaust gas pressure reduced to the same level of commonly used turbochargers at all engine speed. Furthermore, results of the transient experiment showed that PWS had as good response as the small turbocharger, which was optimized for the tested engine.


2016 ◽  
Author(s):  
M. Sheykholeslami ◽  
Y. Hojjat ◽  
S. Cinquemani ◽  
M. Tarabini ◽  
M. Ghodsi

Sign in / Sign up

Export Citation Format

Share Document