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Using turbulators, obstacles, ribs, corrugations, baffles and different tube geometry, and also various arrangements of these components have a noticeable effect on the shell and tube heat exchangers (STHEs) thermal-hydraulic performance. This study aims to investigate non-Newtonian fluid flow characteristics and heat transfer features of water and carboxyl methyl cellulose (H₂O 99.5%:0.5% CMC)-based Al₂O₃ nanofluid inside the STHE equipped with corrugated tubes and baffles using two-phase mixture model.

Five different corrugated tubes and two baffle shapes are studied numerically using finite volume method based on SIMPLEC algorithm using ANSYS-Fluent software.

Based on the obtained results, it is shown that for low-mass flow rates, the disk baffle (DB) has more heat transfer coefficient than that of segmental baffle (SB) configuration, while for mass flow rate more than 1 kg/s, using the SB leads to more heat transfer coefficient than that of DB configuration. Using the DB leads to higher thermal-hydraulic performance evaluation criteria (THPEC) than that of SB configuration in heat exchanger. The THPEC values are between 1.32 and 1.45.

Using inner, outer or inner/outer corrugations (outer circular rib and inner circular rib [OCR+ICR]) tubes for all mass flow rates can increase the THPEC significantly. Based on the present study, STHE with DB and OCR+ICR tubes configuration filled with water/CMC/Al₂O₃ with f = 1.5% and d_np = 100 nm is the optimum configuration. The value of THPEC in referred case was 1.73, while for outer corrugations and inner smooth, this value is between 1.34 and 1.57, and for outer smooth and inner corrugations, this value is between 1.33 and 1.52.

A numerical simulation of a two‐phase dilute flow (droplet‐gas mixture) is carried out by using a finite volume method based on Riemann solvers. The computational domain represents a one‐ended pipe with holes at its upper wall which lead into an enclosure. The aim of this study is to determine the parameters of such a flow. More specially, an analytical solution is compared with numerical results to assess the mass flow rates through the vents in the pipe. Inertia effects dominate the dynamic behaviour of droplets, which causes a non‐homogeneous flow in the cavity. The unsteady effects are also important, which makes isentropical calculation irrelevant and shows the necessity of the use of CFD tools to predict such flows. No relation can be extracted from the numerical results between the gas and the dispersed mass flow rates across the holes. But a linear variation law for the droplet mass flow versus the position of the holes is pointed out, which is independent of the incoming flow when the evaporating effects are quite low.

Nanofluid exhibits higher density, higher viscosity, higher thermal conductivity and reduced specific heat capacity along with improved heat transfer characteristics. It is comparatively better than conventional fluids in terms of thermo-physical properties. This paper aims to investigate experimentally the overall performance of the shell and tube heat exchanger operated under two different configurations – without baffles (STHX_1) and with baffles (STHX_2) using 0.01 Vol.% and 0.02 Vol.% of CuO-W nanofluid.

Two different configurations, one without baffles (STHX_1) and other with single segmental baffles (STHX_2), are chosen with all other dimensional details of shell and tube remaining same. Water is used as base fluid. CuO nanoparticle is chosen, as its thermal conductivity is higher compared to other metal oxides. A comparative study on the thermal performance of these shell and tube heat exchangers are performed by considering different Vol.% concentrations of CuO-W nanofluid and the outcome are compared with the base fluid (i.e., water). The influence of varying the mass flow rate of the tube side fluid by keeping shell side fluid mass flow rate as constant and vice versa on the thermal performance of shell and tube heat exchanger are studied.

The modified shell and tube heat exchanger with baffles (STHX_2) give an improved performance. The heat transfer coefficient improved by about 11.28 and 7.54 per cent for 0.02 and 0.01 Vol.% of CuO-W nanofluid compared to water. Overall heat transfer coefficient for STHX_2 enhanced between 118.26% to 123.06% in comparison with base fluid for 0.02 Vol.% of CuO-W nanofluid whereas, it improved between 79.20% to 87.51% for 0.01 Vol.% of CuO-W nanofluid. Similarly, the actual heat transfer enhanced between 71.79% to 77.77% and between 48.71% to 55.55% for 0.02 and 0.01 Vol.% of CuO-W nanofluid, respectively. Moreover, mass flow rates of the working fluids significantly influence the performance of the shell and tube heat exchanger.

Two cases are considered here. first, by varying the shell side fluid mass flow rate and keeping the tube side fluid mass flow rate as constant. Later, tube side fluid mass flow rates are varied and shell side fluid mass flow rate is kept constant. It is found that in Case 2, for both 0.01 and 0.02 Vol.% of CuO-W nanofluid, highest performance is obtained for 150 kg/h of shell side and tube side fluid flows involving STHX_2. Finally, the modified shell and tube heat exchanger with baffle arrangement gives the best performance by using 0.02 Vol.% of CuO-W nanofluid.

This work presents a numerical study of the dynamic and thermal behavior of a turbulent flow in a shell and tube heat exchanger equipped with a new design of baffle type wing. The implementation of this type of baffle makes it possible to lengthen the path of the fluid in the shell, to increase the heat flux exchanged on the one hand and is to capture the weakness of the shell and tube heat exchanger with segmental baffles on the other hand.

This paper aims to analyze numerically the thermo-convective behavior of water using CFD technique by solving the conservation equations of mass, momentum and energy by the finite volume method based on the SIMPLE algorithm for coupling velocity-pressure. To describe the turbulence phenomenon, the Realizable k–ε model is employed. The analysis is done for different mass flow rates. The parameters studied are: the fluid outlet temperature, the average heat transfer coefficient, the pressure drop, the total heat transfer rate, the effect of the geometric shape of the baffle on the thermal behavior. The purpose of this study is to propose a new design of a shell and tube heat exchanger with a high heat transfer coefficient and a lower pressure drop compared to a shell and tube heat exchanger with transverse and segmental baffles.

The results showed that the use of the wing baffles enhanced the heat transfer coefficient significantly and reduced the friction coefficient. Compared with segmental baffles, the wing baffles are 11.67, 18.53 and 11.5 per cent lower in the pressure drop and 1.79, 1.9 and 2.39 per cent higher in the Nusselt number for the three mass flow rates 0.5, 1 and 2 kg/s, respectively.

The originality of this work lies in proposing a three-dimensional analysis for a novel heat exchanger.

Joint descriptions of both heat and mass transfer and thermodynamic aspects of air‐cooling applications cannot be easily found in the literature. Numerical analyses are a notable exception since suitable physical models and realistic boundary conditions are a prerequisite of accurate simulations. Thus, it is believed that the experience gained with numerical simulations might be of some help also to designers of air‐conditioning and drying systems. This paper seeks to address this issue.

In the text, the physical implications of governing equations and boundary conditions utilized in numerical simulations are extensively discussed. Particular attention is paid to the thermodynamically consistent definition of latent and sensible heat loads, and to the correct formulation of the heat and mass transfer analogy.

Comparisons of analytical and numerical results concerning forced flows of humid air over a cooled plate validate the assumptions made in numerical simulations, both for air‐conditioning applications (almost always characterized by low rates of mass convection) and drying applications (almost always characterized by high rates of mass convection).

Finally, with reference to the cold plate problem investigated here, the effects of the suction flow induced by condensation on the Nusselt number are quantified.

The purpose of the paper is to predict the erosion rate of the components of centrifugal pump under certain operating condition to identify the maximum erosion area and to discuss the factors affecting them. This helps to optimize design and estimate service life.

In the paper, the Eulerian–Lagrangian approach method coupled with the erosion model to investigate the mixed sand characteristics on erosion characteristics of centrifugal pump flow-through wall. The hydraulic performance and wear characteristics experiment of the pump is used to verify the accuracy of the numerical simulation.

The blade erosion area mainly occurs near the blade inlet and the trailing edge of the pressure surface, the main erosion area of the impeller back shroud is near the outlet of the flow passage and the main erosion area of the volute is near the tongue and the I section. With the change of the average diameter and density of sand particles, the average erosion rate on different flow-through walls is positively correlated with the average mass concentration to a certain extent. However, for different sand shape factors, there is little correlation between the average erosion rate and the average mass concentration. In addition, compared with other erosion areas, the increase of average sand particle diameter and density has the greatest impact on the total erosion rate of blade pressure surface, while the shape of sand particles has a greater impact on the total erosion rate of each flow-through wall of centrifugal pump.

In this work, according to the characteristics of the mixed distribution of different sand diameters in the Yellow River Basin, the erosion characteristics of centrifugal pumps used in the Yellow River Basin are studied. The numerical calculation method for predicting the wall erosion of centrifugal pump is established and compared with the experimental results. The results can provide reference for optimizing design and increasing service life.

The purpose of this paper is to present detailed algorithms for simulation of individual and group control of production wells in hydrocarbon reservoirs which are implemented in a finite volume-based reservoir simulator.

The algorithm for individual control is described for the multi-lateral multi-connection ones based on the multi-segment model considering cross-flow. Moreover, a general group control algorithm is proposed which can be coupled with any well model that can handle a constraint and returns the flow rates. The performance of oil production process based on the group control criteria is investigated and compared for various cases.

The proposed algorithm for group control of production wells is a non-optimization iterative scheme converging within a few number of iterations. The numerical results of many computer runs indicate that the nominal power of the production wells, in general, is the best group control criterion for the proposed algorithm. The production well group control with a proper criterion can generally improve the oil recovery process at negligible computational costs when compared with individual control of production wells.

Although the group control algorithm is implemented for both production and injection wells in the developed simulator, the numerical algorithm is here described only for production wells to provide more details.

The proposed algorithm can be coupled with any well model providing the fluid flow rates and can be efficiently used for group control of production wells. In addition, the calculated flow rates of the production wells based on the group control algorithm can be used as candidate solutions for the optimizer in the simulation-optimization models. It may reduce the total number of iterations and consequently the computational cost of the simulation-optimization models for the well control problem.

A complete and detailed description of ingredients of an efficient well group control algorithm for the hydrocarbon reservoir is presented. Five group control criteria are extracted from the physical, geometrical and operating conditions of the wells/reservoir. These are the target rate, weighted potential, ultimate rate and introduced nominal power of the production wells. The performance of the group control of production wells with different group control criteria is compared in three different oil production scenarios from a black-oil and highly heterogeneous reservoir.

Solar energy applications are limited because of its intermittent and discontinuous availability with respect to time. Hence, solar energy thermal conversion systems need integration with thermal storage units (TSUs) to use solar energy in off sunshine hours. This paper aims to perform thermal analysis of a solar air heater (SAH) integrated with a phase change material (PCM)-based TSU to supply hot air during night period.

An experimental setup with TSU as main component was prepared with SAH at its upward side, food chamber at its downward side as subcomponents. In TSU, paraffin wax was used as thermal energy storage material. Mass flow rate of air considered as an input parameter in the experiment. Two different absorber plates, namely, plane and ribbed absorber plates were used for the experimentation. Each day for a fixed mass flow of air, observations were made during charging and discharging of PCM.

Nusselt number and convection heat transfer coefficients were analytically calculated by considering flow through TSU as external flow over bank of tubes in a rectangular duct. A temperature drop of around 7-8°C during charging of PCM and temperature rise of around 4-5°C during discharging of PCM was observed from the experimental results. The average practical efficiency of TSU with ribbed absorber plate SAH during charging and discharging of PCM was 22 and 6 per cent, respectively, higher than that of TSU with plane absorber plate SAH.

There are no limitations for research on SAH integrated with TSU. Different PCM including paraffin wax, Glauber’s salt, salt hydrates and water are used for thermal storage. Only limitation is lower efficiency of SAH integrated with TSU because of lower heat transfer coefficients with air as working medium. If it can improve heat transfer coefficients of air then heat transfer rates with these units will be higher.

There are no practical limitations for research on SAH integrated with TSU. Sophisticated instrumentation is needed to measure flow rates, temperatures and pressure variations of air.

In poultry farms during night, chicks cannot survive at cold climatic conditions. Hence, hot air should be supplied to poultry farms whenever the atmospheric temperature drops. It is proposed that, in combination with TSUs, heat produced by SAH is stored in day time in the form of either sensible or latent heat and is retrieved to provide hot air in the night times. This will reduce total operating costs in poultry farms.

Conventionally, people are producing hot air by combusting coal in poultry forms. This cost around Rs. 75,000 per month for a batch of 225 to 250 chicks in a poultry form. Hot air could be produced economically during off sunshine hours from SAH integrated with TSU compared to the conventional method of coal burning. Present experimental investigations conducted to fill the literature gap in this area of research and to design a SAH integrated with TSU to produce hot air for poultry forms.

This paper aims to present an experimental investigation and optimization of a low-temperature thermoelectric module to examine the influence of the main operating conditions.

In this work, a comparison was made by varying the various operating parameters such as heat source temperature, the flow rate of the cold fluid and the external load resistance. A Taguchi method was applied to optimize the parameters of the system. Three factors, including the external load resistance, mass flow rate of water (at the heat sink side) and heater temperature (at the heat source side) along with different levels were taken into account. Analysis of variance was used to determine the significance and percentage contribution of each parameter.

The experimental results show that the maximum power output 8.22W and the maximum conversion efficiency 1.11 per cent were obtained at the heater temperature of 240°C, the cold fluid mass flow rate of 0.017 kg/s, module temperature difference of 45°C and the load resistance of 5 O. It was observed that the optimum parameter levels for maximum power output determined as 5 O external load resistance, 0.17 kg/s mass flow rate of water and 240°C heater temperature (A1B3C3). It reflects that these parameters influence on the optimum conditions. The heater temperature is the most significant parameter on the power output of the thermoelectric module.

It is clear from the confirmation test that experimental values and the predicted values are in good agreement.

The purpose of this paper is to study the radiation‐natural convection interactions in a vertical divided vented channel. The effects of the surface emissivity, the vent opening position and size on the heat transfer and the flow structures inside the channel were studied.

The governing differential equations are solved by a finite volume method, with adopting the SIMPLER algorithm for pressure‐velocity coupling. The view factors were determined by using a boundary elements approximation and a Monte Carlo method.

The effect of the radiation exchange is very important, it increases the average hot wall Nusselt number by more than 100 per cent. The contribution of the channel wall emissivity in the heat transfer is more important than that of the plate emissivity. The average hot wall Nusselt number increases with increasing the vent opening size, only in presence of the radiation exchange, and this increase is more pronounced, particularly when the vent opening is located near the channel inlet.

The flow is assumed to be incompressible, laminar and two dimensional. The radiative surfaces are assumed diffuse‐grey. The working fluid, air, is considered as transparent with respect to the radiation.

The industrial applications of this study are solar collectors, thermal building, electronic cooling, aeronautics, chemical apparatus, nuclear engineering, etc.

In comparison to the preceding studies, the originality of this paper is the taking into account of the radiation exchange in a vented and divided channel.