Forming the air-core, is the one of flow properties in hydrocyclone. The swirling flow causes a cylindrical low pressure area at the axis of hydrocyclone which is constant throughout the entire length of the hydrocyclone. Air-core affects the separation efficiency. In this study, low pressure areas were used to predict air-core diameter. COMPUTATIONAL FLUID DYNAMICS ((CFD)) method was used to determine the pressure distribution inside of hydrocyclone. Three models including: the renormalization group k-e model, the Reynolds stress model, and the large-eddy simulation model, were compared for the prediction of aircore dimension. Air-core diameter was evaluated by using three planes, one on cylindrical part and two on conical section. Results show that, the RSM turbulence model is more accurate than two other models.

Blood is one of the vital FLUIDs of the human body. Measurement of its viscosity and other properties is very important in detecting and understanding different cardiovascular diseases. In this study, the blood flow in a concentric cylinder viscometer was simulated numerically. The blood flow patterns were analyzed by applying different rotational speed of inner cylinder. Creation of a Couette flow, end effects and suitable rotational speed limit were analyzed. The amount of the torque applied to the inner cylinder which prevents the generation of the Taylor vortices was also predicted. From the obtained results, one can conclude that these vortices were not as important as the end effects were. In order to keep the blood sample temperature within a constant and acceptable range a thermal bath was used. Heat removal rate with different inflow rates of coolant was also predicted numerically.

Gasoline produced from FLUID catalytic cracking (FCC) units contains substantial amounts of sulfur, which contributes to pollution. This study focuses on the hydro-desulfurization of gasoline in a fixed-bed reactor using COMPUTATIONAL FLUID DYNAMICS ((CFD)). The study provides a comprehensive analysis of reactor performance by investigating various parameters such as velocity, pressure, and temperature contours at different sections of the reactor. The visualization of these variations helps understand the hydro-desulfurization process in greater detail and aids in optimizing desulfurization technology. The simulations were conducted and validated results using operational data from the hydrogen refining unit of Abadan Oil Refining Company. The highest temperature was observed along the central line of the reactor, and the maximum pressure drop occurred in the catalytic section. The concentration of hydrogen sulfide (H2S), a product of the hydro-desulfurization reaction, increased by 15-fold and reached 0.008 kmol/m3 as it moves moved from the entrance to the outlet of the reactor. Additionally, the productivity of the reaction, as well as the molar concentration of H2S, increased with an increase in the feed mass flow rate. However, it should be noted that an increase in the feed temperature resulted in higher reaction yields, but it might also lead to the reduced thermal resistance of the catalyst, potentially affecting its effectiveness. Additionally, the concentration of gasoline and hydrogen decreased from the reactor inlet to the outlet, while the concentration of H2S increased.

In this study, the FLUID flow together with solid particles has been studied using COMPUTATIONAL FLUID DYNAMICS ((CFD)). The gas-solid flow (air and sand particles with the size of 150 µm) inside a 76.2 mm diameter pipe with various bend angles including 45, 60, 90, 120, 135, and 180° was modelled at the FLUID flow velocity of 11 m/s. The k-ω turbulence model was employed to model the flow turbulence and the E/CRC erosion model have been used to predict erosion rates. The hydroDYNAMICS of the flow, the particles motion as well as the probable erosion regions were predicted. The (CFD) simulation results showed that increasing the curvature angle increases the erosion rate. While, increasing the pipe diameter, decreases the erosion rate. The maximum erosion rate was predicted at the end part of the curvature for 45 and 60 ° angles, while it was observed in the middle region for 120 and 135 ° curvatures. Finally, the maximum erosion rate for the 180 ° curvature was observed in two regions at the end of the first and second half. Using these results, precautionary considerations for the erosion, and the suitable plans for the repair and maintenance of the equipment can be offered.