Aim of study: Novel configurations of separation chamber are proposed to resolve the critical issue of separation in agro-industrial equipment.Area of study: Dept. of Mechanical and Biosystems Engineering, Urmia, IranMaterial and methods: Precise and instrumented experimentation has been conducted to calibrate the computational fluid dynamics (CFD) methodology in the modeling and simulating chickpea pod separation. Mechanisms were selected based on optimizing separation efficiency, relative purification and required airflow as a criterion for energy consumption.Main results: Applying a guiding blade and suction fans may potentially increase the separation efficiency while reducing the relative purification and required airflow. The highest separation efficiency (95%), the lowest required airflow (545 m³/h) and the lowest pressure drop (16.3 Pa), were obtained by such configuration. Furthermore, the highest relative purification of 90% was achieved when the mechanism was free of blade and fans.Research highlights: To integrate the advantages of the above-mentioned configurations, a series-type assembling them is proposed to preserve the separation efficiency and relative purification at the highest level, meanwhile reducing the required airflow. Also, 15% enhancement in the separation efficiency and 302.8 m³/h reductions in the airflow were found as a crucial finding. The high correlation of experimental and theoretical CFD results is the key point to motivate the researchers for extension of similar case projects.

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Energy saving in the food industry is of a great deal of importance. Thermal vapor compressors (TVCs) do not have moving parts which offer advantages including simplicity, low construction capital, and low maintenance costs. In this study, a TVC is designed, and simulated to recover waste vapor streams and reuse the recovered streams in the crystallization of sugar. Computational fluid dynamics is employed to simulate the flows. The effect of motive steam pressure on the entrainment ratio and compressor ratio is simulated. Thermodynamics parameters such as static pressure, temperature, velocity, Mach number, and mass ratios of motive steam and suction are assessed. As the flow is of jet flow type, the realizable k‐e turbulent model is used to model the turbulence. The results show that by applying the motive steam at a pressure of 28 bars (boiler outlet), the pressure and temperature of discharge vapor reach the values of 0.65 bar and 511 K, respectively. The average mass ratios of motive and suction flow at the output of the designed TVC diffuser are 0.59 and 0.41, respectively. As the crystallization pressure demand is 0.6 bar, the findings reveal that the discharged vapor from TVC has sufficient enthalpy to be consumed in the crystallization section, hence making the whole process more efficient. Practical application Equipping the crystallization section of the sugar factory with a thermal vapor compressor, beside the recovery of low‐pressure vapor with motive steam, can reduce energy consumption and play a key role in decreasing fossil pollution. Computational Fluid Dynamics is a validated tool in the simulation of the food processing phenomenon. In terms of TVC optimization, the results obtained from this research serve to designers and process managers to get a detailed perception of energy reduction scenarios and recovery of low enthalpy streams.

Optimum design of the conveying process plays a key role in the enhancement of system performance. In this study, a critical section of a larvae killing system in wheat conveying was evaluated experimentally and numerically. Three elbow angles of 105, 120, and 135° according to physical constraints were assessed to achieve the best conveying condition. Computational fluid dynamics (CFD) was used to obtain numerical results. Also, the Reynolds stress model (RSM) and discrete phase method (DPM) were applied to simulate the turbulences and interaction between solid–gas phases, respectively. The results showed that a minimum pressure drop of 131 Pa occurred in the 120° configuration, and this configuration has the best development from the velocity magnitude viewpoint. Of note, the lowest vorticity magnitude (as a positive factor in safe conveying) was obtained for the 120° configuration in which the vorticity magnitude 63% less than 105°. Also, the contours of turbulence intensity and erosion, comprehensively investigated. Considering all aspects, the 120° configuration was selected as the optimum conveying angle in the larvae killing system. Practical applications The larvae killing system is the main part of the wheat conveying processes. The optimal condition of conveying could be obtained using new numerical methods. Computational fluid dynamics is a powerful method in the simulation of process phenomena. The results achieved from this research could be utilized for energy saving through decreasing the pressure drop, besides understanding of flow field within the system.

In this study, as a novelty, the reverse flow effect on a wheat flour cyclone performance was evaluated. A computational fluid dynamics (CFD) simulation was realized using a Reynolds stress turbulence model. Also, particle-air interactions were modeled applying a discrete phase model. Besides the experimental measurement, the numerical simulation was conducted in a main (without reverse flow) and six various reverse flow levels (I = 0.0385 m 3 s À1 , II = 0.0396 m 3 s À1 , III = 0.0484 m 3 s À1 , IV = 0.0583 m 3 s À1 , V = 0.0704 m 3 s À1 , and VI = 0.0836 m 3 s À1 ) by CFD. The validation between pressure drop in experimental data and numerical results revealed a good agreement with a maximum deviation of 8.2%. Cyclone performance including pressure drop and separation efficiency was assessed in the mentioned reverse flow levels. Moreover, velocity field, centrifugal force, and turbulence parameter were evaluated, comprehensively. It was found that the flour separation efficiency increased with enhancing the reverse flow level to IV = 0.0583 m 3 s À1 , but decreased with a sharp slope in the reverse levels of V = 0.0704 m 3 s À1 and VI = 0.0836 m 3 s À1 . Practical ApplicationsCyclone separators are widely used in various industries such as flour and cement.The various parameters of cyclones in a food processing unit effectively affect cyclone efficiency. Therefore, an innovative method for increasing cyclone performance is presented in this study. Computational fluid dynamics (CFD) is a powerful tool for simulation of the food processing phenomenon. Validation could be guaranteed by the usage of numerical results that are obtained from CFD simulations. The innovative methods can play a key role in decreasing energy usage by reducing the pressure drop and enhancing separation efficiency.