Mehdi Jahangiri

[ 1 ] - Investigation of the Slipping Wear based on the Rate of Entropy Generation

Wear is a complicated phenomenon caused by the relative movement of two contacting surfaces compressed together by a normal force. Prediction of the wear, in most cases, requires various experiments and microstructural characterization of the contacting surfaces. Mathematical models based on physical concepts could provide considerable help in understanding the physical behavior and hence the p...

[ 2 ] - Investigation on Wear Behavior of W-Cu Nanocomposite Fabricated Through Thermochemical Synthesis

In this work, homogeneous thermochemical co-precipitation method was used to fabricate W-25wt%Cu nanocomposite. Synthesized nanocomposite powder was calcined and reduced. A hydrogen atmosphere sintering at 1200oC for 105 consolidated the product up to a density close to 98% theoretical density. Wear experiment were carried out using a pin-ondisc set up at three normal loads of 5, 10 and 15 N an...

[ 3 ] - 3-D Numerical Investigation of Flow Field in Starting Stage of High Speed Wind Tunnels

High speed wind tunnels are widely used in the study of fluid flow behavior around various objects. The air flow in the starting step of supersonic wind tunnels is transient including strong shock waves caused by the interaction of the tunnel main stream and the boundary layer at walls. To arrive in running step, the tunnel must be designed so as these waves leave immediately the test section. ...

[ 4 ] - اصلاح عملکرد سیستم HVAC با استفاده از شبیه سازی عددی و مقایسه با نتایج تجربی

در این مقاله یک سیستم تهویه مطبوع HVAC از نوع تراکمی مورد مطالعه و بررسی قرار گرفته است. هدف از این مطالعه بهبود عملکرد سیستم تبرید، رفع یخ زدگی کمپرسور، بالابردن راندمان، کاهش مصرف انرژی و کاهش مدت زمان کارکرد کمپرسور بوده است. نتایج حاصل از داده های تجربی و حل عددی دینامیک سیالات محاسباتی مقایسه و تفسیر شده است. پس از رفع عیب، نتیجه تعمیرات صورت گرفته با استفاده از حل عددی و توسط کانتورها و ن...

[ 5 ] - Investigation of the Slipping Wear based on the Rate of Entropy Generation

Wear is a complicated phenomenon caused by the relative movement of two contacting surfaces compressed together by a normal force. Prediction of the wear, in most cases, requires various experiments and microstructural characterization of the contacting surfaces. Mathematical models based on physical concepts could provide considerable help in understanding the physical behavior and hence the p...

[ 6 ] - Investigation on Wear Behavior of W-Cu Nanocomposite Fabricated Through Thermochemical Synthesis

In this work, homogeneous thermochemical co-precipitation method was used to fabricate W-25wt%Cu nanocomposite. Synthesized nanocomposite powder was calcined and reduced. A hydrogen atmosphere sintering at 1200oC for 105 consolidated the product up to a density close to 98% theoretical density. Wear experiment were carried out using a pin-ondisc set up at three normal loads of 5, 10 and 15 N an...

[ 7 ] - 3-D Numerical Investigation of Flow Field in Starting Stage of High Speed Wind Tunnels

High speed wind tunnels are widely used in the study of fluid flow behavior around various objects. The air flow in the starting step of supersonic wind tunnels is transient including strong shock waves caused by the interaction of the tunnel main stream and the boundary layer at walls. To arrive in running step, the tunnel must be designed so as these waves leave immediately the test section. ...