Dibakar Das | Bangladesh University of Engineering & Technology (original) (raw)
- Graduated in Mechanical Engineering from Bangladesh University of Engineering & Technology
- Proficient in some Design, Coding and Simulation Software such as Solidworks, Autocad, COMSOL, Atmel Studio, Arduino, Tecplot etc
- Good Communication skills both in Bangla and English
- Hard working, Attentive, Responsible and very eager to learn
- Good teamwork skill
Supervisors: Dr. Mohammad Mamun and Dr. Sumon Saha
Phone: 01911213120
Address: 49/B, R.K.Mission Road, Gopibag, Dhaka
less
Uploads
Thesis Chapters by Dibakar Das
In the 21st century, automobile industries are increasing at an unimaginable space. A huge proble... more In the 21st century, automobile industries are increasing at an unimaginable space. A huge problem of internal combustion (IC) engines is that it is a main cause of noise pollution. That is the reason mufflers are used to reduce the noise produced. Though mufflers are not designed to serve any primary exhaust function, they are installed within the exhaust system of most IC engines. It is designed as a soundproofing device that reduces the loudness of the pressure created by the engine. But mufflers need design and geometry considering the physics behind it which is very confounded. Established muffler design has been an iterative process by trial and error method. With recent research in this area has made it possible to do it in an analytical and experimental way.
There are two types of muffler, absorption type muffler and reactive muffler. The project dealt with the complexity behind the different mufflers and finally designed and constructed an absorption type muffler. After constructing the muffler according to our design using mild steel sheet and steel wool, we compared its performance based on three cases, no muffler condition, laboratory muffler condition and our newly designed muffler condition. Each case we calculated the insertion loss, brake specific fuel consumption (BSFC) and specific fuel consumption (SFC). And finally we showed with graphical representation that, our designed muffler performed better than the laboratory muffler condition and no muffler condition.
Of course, we did not achieve our desired result, since mild steel is no longer used as the construction material anymore and the available steel wool was not quality as we expected. However, we hope using better construction material and our design will certainly reduce the sound pressure level a great deal.
Papers by Dibakar Das
International Conference on Mechanical Engineering (ICME), 2017
The present numerical study deals with the effect of different heat conducting thick bottom wall ... more The present numerical study deals with the effect of different heat conducting thick bottom wall materials on mixed convection inside a lid-driven trapezoidal cavity filled with nanofluid. The top wall of the cavity is considered as isothermal cold surface, and is moving at a constant speed in its own plane. The solid bottom wall is heated whose lower surface temperature is varied sinusoidally, and three different materials such as glass fiber, plexiglas and dry concrete are selected as heat conducting thick wall. The cavity is filled with water-Al2O3 nanofluid. The non-dimensional Navier-Stokes and the thermal energy equations are used as governing equations for this problem, and finite element method is used to solve those equations. Numerical simulation is performed in pure mixed convection regime by varying parameters such as Reynolds and Grashof numbers simultaneously within the range of 0.1 ≤ Re ≤ 2×104 and 10-2 ≤ Gr ≤ 4×108 , and thus the Richardson number is maintained as unity. The influence of working fluid (both pure fluid and nanofluid) on the average Nusselt number of the top surface of the thick bottom wall is observed for different heat conducting materials. Results show that the materials of the thick wall with high thermal conductivity demonstrate better performance in convection dominated regime than those with low thermal conductivity.
In the 21st century, automobile industries are increasing at an unimaginable space. A huge proble... more In the 21st century, automobile industries are increasing at an unimaginable space. A huge problem of internal combustion (IC) engines is that it is a main cause of noise pollution. That is the reason mufflers are used to reduce the noise produced. Though mufflers are not designed to serve any primary exhaust function, they are installed within the exhaust system of most IC engines. It is designed as a soundproofing device that reduces the loudness of the pressure created by the engine. But mufflers need design and geometry considering the physics behind it which is very confounded. Established muffler design has been an iterative process by trial and error method. With recent research in this area has made it possible to do it in an analytical and experimental way.
There are two types of muffler, absorption type muffler and reactive muffler. The project dealt with the complexity behind the different mufflers and finally designed and constructed an absorption type muffler. After constructing the muffler according to our design using mild steel sheet and steel wool, we compared its performance based on three cases, no muffler condition, laboratory muffler condition and our newly designed muffler condition. Each case we calculated the insertion loss, brake specific fuel consumption (BSFC) and specific fuel consumption (SFC). And finally we showed with graphical representation that, our designed muffler performed better than the laboratory muffler condition and no muffler condition.
Of course, we did not achieve our desired result, since mild steel is no longer used as the construction material anymore and the available steel wool was not quality as we expected. However, we hope using better construction material and our design will certainly reduce the sound pressure level a great deal.
International Conference on Mechanical Engineering (ICME), 2017
The present numerical study deals with the effect of different heat conducting thick bottom wall ... more The present numerical study deals with the effect of different heat conducting thick bottom wall materials on mixed convection inside a lid-driven trapezoidal cavity filled with nanofluid. The top wall of the cavity is considered as isothermal cold surface, and is moving at a constant speed in its own plane. The solid bottom wall is heated whose lower surface temperature is varied sinusoidally, and three different materials such as glass fiber, plexiglas and dry concrete are selected as heat conducting thick wall. The cavity is filled with water-Al2O3 nanofluid. The non-dimensional Navier-Stokes and the thermal energy equations are used as governing equations for this problem, and finite element method is used to solve those equations. Numerical simulation is performed in pure mixed convection regime by varying parameters such as Reynolds and Grashof numbers simultaneously within the range of 0.1 ≤ Re ≤ 2×104 and 10-2 ≤ Gr ≤ 4×108 , and thus the Richardson number is maintained as unity. The influence of working fluid (both pure fluid and nanofluid) on the average Nusselt number of the top surface of the thick bottom wall is observed for different heat conducting materials. Results show that the materials of the thick wall with high thermal conductivity demonstrate better performance in convection dominated regime than those with low thermal conductivity.