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In this investigation, a comprehensive approach is established in detail to analyse the effectiveness of the shell and tube heat exchanger (STE) with 50% baffle cuts (Bc) with varying number of baffles. CFD simulations were conducted on a single pass and single tube heat exchanger(HE) using water as working fluid. A counterflow technique is implemented for this simulation study. Based on different approaches made on design analysis for a heat exchanger, here, a mini shell and tube exchanger (STE) computational model is developed. Commercial CFD software package ANSYS-Fluent 14.0 was used for computational analysis and comparison with existing literature in the view of certain variables; in particular, baffle cut, baffle spacing, the outcome of shell and tube diameter on the pressure drop and heat transfer coefficient. However, the simulation results are more circumscribed with the applied turbulence models such as Spalart-Allmaras, k-ɛ standard and k-ɛ realizable. For determining the best among the turbulence models, the computational results are validated with the existing literature. The proposed study portrays an in-depth outlook and visualization of heat transfer coefficient and pressure drop along the length of the heat exchanger(HE). The modified design of the heat exchanger yields a maximum of 44% pressure drop reduction and an increment of 60.66% in heat transfer.

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A numerical examination of the two-phase flow inside a hydrocyclone was conducted to quantify the turbulent velocity fluctuations. The simulations were conducted using the large eddy simulation (LES) approach comparing various subgrid-scale models. The numerical results were compared to published LDV data [7]. The study indicated that the tangential velocity is an insensitive parameter for validation because the fluctuations are less pronounced. In contrast, the turbulent fluctuations in the axial and tangential directions show substantial variations when modeled with increasingly larger mesh sizes. The numerical results also confirmed that the RMS velocity profiles predicted by the LES-Smagorinsky model provide a good prediction for the axial turbulent velocity fluctuations. The results also show that the LES-VOF approach predicts the split ratio of the product with a 0.45% error compared to the experimental data.