Showing 3 results for Fazel
Seid H. Pourtakdoust, S.a. Fazelzadeh Haghighi,
Volume 18, Issue 1 (4-1999)
Abstract
Guidance and control of aircraft in the landing phase imposes extra pilot work loads, hence application of automatic landing control systems is of great importance. In this study automatic landing control systems are introduced and an optimal landing control system is designed. The control system performance criteria are based on minimum control effort. The designed system is simulated for a transport category aircraft in accordance with FAR requirements. The results show that the designed system is completely capable of controlling the aircraft in its landing corridor.
M. R. Soltani, H. Fazeli, B. Farahanieh and A. R. Davari,
Volume 21, Issue 1 (7-2002)
Abstract
An extensive experimental investigation to understand the aerodynamic behavior of wrap around fin (WAF) missile configuration has been conducted. Various tests using at first a standard model (TTCP) in the trisonic wind tunnel of Imam Hossein University has been performed. The tunnel has attest section of 60×60 cm2 and can operate at Mach numbers of 0.4≤M∞≤2.2 and at attack angles of -4˚≤α≤10˚. Experimental longitudinal results are compared with those of NASA and an engineering code. The results for TTCP model are in good agreement. After gaining confidence on the TTCP results, a new model of WAF rocket was designed, built and tested. This paper compares the results of two models tested under the same conditions.
Keywords: Wind tunnel, Wrap around fin, Missile, Balance WAF-TTCP
M. Fazel, M.r. Garsivaz Jazi1, S. Bahramzadeh, S.r. Bakhshi, M. Ramazani, A. Bahramian,
Volume 34, Issue 1 (Journal of Advanced Materials-Spring 2015)
Abstract
Ni–SiC composite coatings are successfully employed as a protective coating in the inner walls of engine cylinders. In this study, Ni-SiC, Ni-SiC-MoS2 and Ni-SiC-Gr composite coatings were prepared from a sulfamate bath. Both mechanical and ultrasonic stirring were used simultaneously during the process. Taking into account the working temperature of engine cylinders, the wear behavior of coatings was evaluated at 25 to 300 ºC and the high temperature tribological properties of the coatings were investigated. Based on the results obtained from the wear tests, all three coatings showed almost good friction coefficient values at 25 and 100 ºC, which were close to each other. By increasing the temperature to 200-300 °C, the friction coefficient and weight loss values strongly increased. However, addition of solid lubricants caused the values to decrease. The Ni-SiC-Gr coating at all temperatures showed a good and stable behavior.
