Loading...

Numerical Simulation and Investigation of Gas Explosion in the Confined Spaces

Arjmand, Ali | 2017

1465 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 49430 (08)
  4. University: Sharif University of Technology
  5. Department: Mechanical Engineering
  6. Advisor(s): Farhanieh, Bijan
  7. Abstract:
  8. Generally speaking, there are two types of self-propagating combustion waves: deflagrations and detonations. deflagrations waves propagate at relatively low subsonic velocities with respect to the reactants ahead of it. The propagation velocity in deflagration wave is of order of 1 to 10 meters per second depend on laminar or turbulent regime. On the other hand, the detonation wave is a supersonic combustion wave (of the order of 2000 m/s) across which the thermodynamic states (e.g., pressure and temperature) increase sharply. It can be considered as a reacting shock wave where reactants transform into products, accompanied by an energy release across it. Due to drastic changes that detonation wave creates in the thermodynamic properties of combustion mixture, the wave if formed, causing severe damage to life and property in the facility and surrounding structures. With that in mind, detonation wave formation, could be considered as worst-case scenario in Risk assessment.Due to the nature detonation wave, experimental study of detonation wave is very costly and in some cases, because of the large amount of damage; is not possible practically. Today, computational fluid dynamics provided the opportunity to simulate detonation wave with acceptable accuracy and low cost compared with the experiment tests. This research is concerned with numerical simulation of detonation in confined spaces. For this purpose, the equations of conservation of mass, momentum, species transport and ideal gas state equations are solved at the same time in transient state. The overall objective of this study is to investigate the effect of different variables such as the initiation energy, fuel equivalence ratio, initial temperature on the pressure, temperature and propagation speed of detonation wave. The results show that with increasing initial temperature of the combustive mixture, the amount of maximum pressure and propagation speed of detonation decreased, but the maximum temperature increased
  9. Keywords:
  10. Numerical Simulation ; Detonation Wave ; Risk Assessment ; Overpressure ; Safety ; Deflagration ; Maximum Over Pressure ; Propagation Velocity

 Digital Object List

 Bookmark

...see more