Empirical correlation derived by CFD simulation on heat source location and ventilation flow rate in a fire room

2016 ◽  
Vol 122 ◽  
pp. 80-88 ◽  
Author(s):  
Ons Tlili ◽  
Hatem Mhiri ◽  
Philippe Bournot
Designs ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 4
Author(s):  
Dillon Alexander Wilson ◽  
Kul Pun ◽  
Poo Balan Ganesan ◽  
Faik Hamad

Microbubble generators are of considerable importance to a range of scientific fields from use in aquaculture and engineering to medical applications. This is due to the fact the amount of sea life in the water is proportional to the amount of oxygen in it. In this paper, experimental measurements and computational Fluid Dynamics (CFD) simulation are performed for three water flow rates and three with three different air flow rates. The experimental data presented in the paper are used to validate the CFD model. Then, the CFD model is used to study the effect of diverging angle and throat length/throat diameter ratio on the size of the microbubble produced by the Venturi-type microbubble generator. The experimental results showed that increasing water flow rate and reducing the air flow rate produces smaller microbubbles. The prediction from the CFD results indicated that throat length/throat diameter ratio and diffuser divergent angle have a small effect on bubble diameter distribution and average bubble diameter for the range of the throat water velocities used in this study.


2016 ◽  
Vol 139 (1) ◽  
Author(s):  
S. Negin Mortazavi ◽  
Donna Geddes ◽  
Fatemeh Hassanipour

This study is a collaborative effort among lactation specialists and fluid dynamic engineers. The paper presents clinical results for suckling pressure pattern in lactating human breast as well as a 3D computational fluid dynamics (CFD) modeling of milk flow using these clinical inputs. The investigation starts with a careful, statistically representative measurement of suckling vacuum pressure, milk flow rate, and milk intake in a group of infants. The results from clinical data show that suckling action does not occur with constant suckling rate but changes in a rhythmic manner for infants. These pressure profiles are then used as the boundary condition for the CFD study using commercial ansys fluent software. For the geometric model of the ductal system of the human breast, this work takes advantage of a recent advance in the development of a validated phantom that has been produced as a ground truth for the imaging applications for the breast. The geometric model is introduced into CFD simulations with the aforementioned boundary conditions. The results for milk intake from the CFD simulation and clinical data were compared and cross validated. Also, the variation of milk intake versus suckling pressure are presented and analyzed. Both the clinical and CFD simulation show that the maximum milk flow rate is not related to the largest vacuum pressure or longest feeding duration indicating other factors influence the milk intake by infants.


Author(s):  
Cha-Sik Park ◽  
Yong-Hee Jang ◽  
Young-Soo Lee ◽  
Yong-Chan Kim

2017 ◽  
Vol 2017 (1) ◽  
pp. 233-237 ◽  
Author(s):  
Elin Fjeld ◽  
Wilhelm Rondeel ◽  
Knut Vaagsaether ◽  
Elham Attar

Author(s):  
Hossein Mohammad Ghasemi ◽  
Neda Gilani ◽  
Jafar Towfighi Daryan

Abstract In the present work, a different new arrangement of side-wall burners of an industrial furnace with varying fuel flow rate was studied by three-dimensional CFD simulation. Tube skin temperature and heat flux profiles were obtained by solving mass, momentum and energy equations of the furnace by Ansys Fluent software. A reasonable fuel flow rate ($$\dot m$$=0.0695 kg/s) was assigned and effect of different ratio of this rate (0.25$$\dot m$$, 0.5$$\dot m$$, 2$$\dot m$$, 4$$\dot m$$) was investigated on reactor tube skin temperature profiles. Heat and temperature non-uniform distribution was observed by proposed arrangement. It was found that proper range for fuel rate was 0.5$$\dot m$$ to 2$$\dot m$$. Temperature profiles were used in one dimensional plug flow reactor model equations to consider fuel rate variations on reactor performance. By the proposed burner arrangement, Propane conversion and Ethylene yield obtained 6.25 % and 7.2 % more than the base case. Furthermore coil outlet temperature (COT) decreased about 7 °C. Also, feed flowrate was taken as an effective parameter on reactor process under no coke formation condition. Results showed that by increasing fuel rate, outlet Propylene yield decreased, while, process gas temperature, pressure drop, process severity (propane conversion) and Ethylene yield increased along the reactor tube i. e. for 0.5$$\dot m$$ to 2$$\dot m$$ at 0.8 kg/s reactor flowrate, Propylene yield decreased 15.95 % and reached to zero, whereas Ethylene yield increased 16.5 %. Also, in any fuel rate, by increasing reactor feed flowrate, even though the reactor coil outlet temperature decreased, the desired product yields increased. At 0.95 kg/s reactor flowrate, maximum Ethylene yield was obtained about 45.5 % at 1$$\dot m$$ kg/s; while, Propylene yield production at 0.5$$\dot m$$ kg/s fuel rate was 22.41 %.


2017 ◽  
Vol 29 (12) ◽  
pp. 122009 ◽  
Author(s):  
Rasul Mohebbi ◽  
Mohsen Izadi ◽  
Ali J. Chamkha

Author(s):  
Racheet Matai ◽  
Savas Yavuzkurt

The performance of an industrial fan was simulated using CFD and results were compared with the experimental data. The fan is used to cool a row of resistor networks which dissipate excess energy generated by regenerative power in an inverter application. It has a diameter of 24 inches (0.6096m) and rotates at different speeds ranging from 2500 to 3900 RPM depending on the requirements. CFD simulation results were also verified by simulating performance of the same fan at different speeds and comparing the results with what was expected from fan affinity laws. The CFD results matched almost exactly (with ∼0.2% difference for pressure at a given flow rate) with the performance being predicted by the affinity laws. The effect of variation of different parameters such as the blade length, number of blades, and blade chord length was studied. Increasing the blade length at the same RPM increased the mass flow rate (by ∼17%) for the same pressure. Increasing the chord length while keeping the same number of blades, at a given RPM, made the performance curve (pressure versus flow rate, i.e. PV curve) steeper and blades stalled at a higher mass flow rate (8.77 kg/sec compared to the previous 8.44 kg/sec). For the same total blade surface area, less number of blades with longer chords stalled at lower mass flow rates (9.22 kg/sec for a 33% shorter chord and 36 blades compared to 8.3 kg/sec for the original rotor which had 24 blades).


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