Faramarz Djavanroodi

Bio: Faramarz Djavanroodi is an academic researcher from Prince Mohammad bin Fahd University. The author has contributed to research in topics: Severe plastic deformation & Ultimate tensile strength. The author has an hindex of 21, co-authored 90 publications receiving 1489 citations. Previous affiliations of Faramarz Djavanroodi include Imperial College London & Qassim University.

Effect of die channel angle, friction and back pressure in the equal channel angular pressing using 3D finite element simulation

Abstract: In this study, deformation behavior of commercial pure aluminum in the equal channel angular pressing (ECAP) is analyzed successfully using three dimensional (3D) simulation by finite element methods (FEM). The investigations include the effects of various die channel angles, low-friction and high-friction conditions and the application of the back punch pressure. It is observed that the level of the strain and homogeneity of strain distribution increase with decreasing the die channel angle or increasing the friction coefficient or imposing the back punch pressure in the outlet channel. Also, increasing the magnitude of the strain causes high punch pressure and higher press pressure for processing should be applied.

Effect of die parameters and material properties in ECAP with parallel channels

Abstract: In this paper, the influences of die parameters (die channel angle and channel displacement) and material properties (strength coefficient and strain hardening exponent) are investigated in equal channel angular pressing with parallel channels (ECAP-PC) using three dimensional (3D) finite element simulation (FEM). It has been shown that die parameters play an important role in the magnitude and homogeneity of effective strain. In general, die channel angle has more influence on the magnitude rather than homogeneity of effective strain, decreasing the die channel angle results in a higher magnitude of effective strain imposed on the sample and a higher pressing force. But on the other hand, channel displacement has more influence on the homogeneity of effective strain, increasing the die channel's displacement results in a more homogenous effective strain on the sample cross-section. Simulation on various strength coefficient and strain hardening exponents showed that the magnitude of the strain hardening exponent does not have much effect on the pressing force. On the other hand, the level of pressing force increases when the magnitude of the strength coefficient is increased.

(Energy, SCI-Q1, Top 10%) - Engine performance and emissions using Jatropha curcas, Ceiba pentandra and Calophyllum inophyllum biodiesel in a CI diesel engine

Abstract: Biodiesel is a recognized replacement for diesel fuel in compressed ignition engines due to its significant environmental benefits. The purpose of this study is to investigate the engine performance and emissions produced from Jatropha curcas, Ceiba pentandra and Calophyllum inophyllum biodiesel in compressed ignition engine. The biodiesel production process and properties are discussed and a comparison of the three biodiesels as well as diesel fuel is undertaken. After that, engine performance and emissions testing was conducted using biodiesel blends 10%, 20%, 30% and 50% in a diesel engine at full throttle load. The engine performance shows that those biodiesel blends are suitable for use in diesel engines. A 10% biodiesel blend shows the best engine performance in terms of engine torque, engine power, fuel consumption and brake thermal efficiency among the all blending ratios for the three biodiesel blends. Biodiesel blends have also shown a significant reduction in CO2, CO and smoke opacity with a slight increase in NOx emissions.

Variability of Mechanical Properties of Reinforcing Bars

Abstract: The results of approximately 4000 published and unpublished tensile tests on deformed reinforcing bars are studied to obtain statistical relationships for various mechanical properties. The sample included No. 3 through No. 18, Grades 40 and 60, bars. The means and coefficients of variation of the mill test yield strengths were found to be 48.8 ksi (337 MN/sq m) and 10.7% for Grade 40 and 71 ksi (MN/sq m) and 9.3% for Grade 60 bars. Beta distributions were used to represent both of these sets of data. The static yield strength was found to be 3.5 ksi (24 MN/sq m) lower on the average than the mill test yield strength in both cases, with a coefficient of variation of 13.4%. The trend to lower yield strengths with increased bar sizes observed early in the 1970's was not present in more resent test data, apparently due to more stringent production control in recent years. /Authors/