Energy and Exergy for Sustainable and Clean Environment, Volume 2

In this paper, a novel fuzzy logic-controlled Vienna rectifier to extract maximum power at variable wind speed is proposed. Vienna rectifier consists of three switches and four diodes with an input inductor and performs both AC/DC and DC/DC conversions in a single stage. A permanent magnet synchronous generator (PMSG) coupled with wind turbine system is used in this paper. The tracking of the maximum power is a real challenge in wind energy systems. In this paper, the variable speed of the wind turbine generator system and the power output of the permanent magnet synchronous generator are chosen as inputs to the fuzzy logic controller to track the maximum power according to the change in wind speed by following 27 set of rules formulated in the fuzzy rule base. The pulse width modulated signals from the fuzzy logic controller initiate the three switches in the Vienna rectifier. The proposed control scheme not only tracks the maximum power from the wind but also enhances the input DC voltage, ensures sinusoidal nature at input mains and balances the voltage across the two capacitors. The Vienna rectifier is interfaced to the grid through space vector pulse width modulated voltage source inverter. The MATLAB/Simulink environment is utilized in order to observe the optimum performance of the system. The proposed control algorithm is experimentally validated using a real-time simulator OPAL RT 4200. The experimental results are in agreement with simulation results and prove the robustness of the control scheme.

In this work, a relative inspection is performed with distributed power flow controller (DPFC) and unified power flow controller (UPFC) connected to a solar–wind hybrid system. The hybrid system consists of dual sources for renewable energy as solar and wind. Solar generation system followed by a boost converter is useful to raise the level of DC power from the solar energy. On the other hand, wind generation system followed by a diode rectifier and boost converter amplifies the energy received from wind source. Now DC obtained from both the sources is coupled to a common DC bus to get the DC link voltage which eventually is applied as input to the grid side two-level voltage source inverter (VSI). The grid side demands control actions and monitoring perfectly due to the presence of distortions, noise, power losses, etc. Reactive elements reduce these problems up to a certain extent, but it increases the possibility of sub-synchronous resonance phenomenon and extra inductive and capacitive losses. Moreover, the power factor is also affected considerably. Thanks to the emerging FACTS technology, which controls as well as increases the utilization of transmission lines to its full thermal limits. Unified power flow controller (UPFC) is one of the latest FACTS devices available today. It controls the power flow through the lines by varying line inductances, transmission angles and voltage magnitude. The disadvantage of UPFC is its immensely high rated three-phase series–shunt converters and the increased ripple content in output grid voltages and currents. These problems are overcome by a newly invented FACTS device, namely distributed power flow controller (DPFC), which uses small single-phase series and shunt converters. The paper studies the effect of incorporating UPFC and DPFC to hybrid solar–wind system. Additionally, working principle of both the devices was presented. At the end, results from MATLAB simulation are used to support the claim of DPFC being superior to UPFC.

The Lighter than Air (LTA) Wind Turbine system utilizes the stronger wind currents at higher altitudes to generate electricity. Suspended in the air with the help of tethers, this system is capable of rotating about its axis which further actuates an onboard AC generator that transfers the current to the ground, where the alternating current is transformed into useful direct current. The envelope and wing design of the system is such that it can operate under conditions with wind flow from two directions and a spherical envelope further increases the balloon’s stability in turbulent weathers due to an acting Magnus effect. Such systems have the efficacy of being used very efficiently in metropolitan cities where the establishment of conventional wind turbines is not feasible due to space constraints. Such lighter than air systems have a huge latent potential in building a sustainable future and this project works towards the manifestation of the same. This paper offers an alternative which can be further worked upon to make a viable solution for this concept.

Renewable power production is getting advancement as an alternative to conventional type power generation. The design of wind turbine blades getting advanced to be efficient, further it needs to exhibit lightweight, durability, high fatigue strength, damage tolerance, the potential of recycling, and stiffness. A lot of efforts were made to upsurge the effectiveness of the wind turbine blades like adding triplets at the edges, biplane blades, blades with moving surfaces. In this work, we tried three different methods for validating the performance of the blades by inducing a hole near the tip of the blades, a material reduction in the tip of the blades with the standard profile of NACA 4415. The results indicated that the standard profile performed better compared to the modified profiles as the velocity at the tip decreases and the pressure on the tip of the blades increased drastically.

A rapid development is taking place in the field of renewable energy sources to increase the power generation because these sources are eco-friendly, non-polluting, freely available in nature sources like solar wind, biomass, hydro, and tidal. These renewable sources are mostly uncontrollable and all the same time different methods should be done to build a power plant to generate a continuous and constant power. The selection of the renewable energy source for the plant is one of the important roles for energy optimization. This is mainly focused toward the solar and wind power combination, whereas the solar system is the major renewable energy source for energy generation. In this work, a dynamic hardware model for an intelligent control-based effective utilization of hybrid renewable energy sources and Battery Management System. It also explains the implementation of fuzzy logic algorithm. The Battery Management System (BMS) is simulated in MATLAB software by using fuzzy logic controller (FLC). BMS explains the charging state and discharging state of battery. Then, it is implemented in hardware model for effective utilization of renewable energy sources. The identification of each subsystem has been made, and then, the proposed system is modeled and simulated using MATLAB—Simulink package. The proposed control strategy has been experimentally implanted, and practical results are compared to those obtained by simulation under the same metrological conditions, showing the effectiveness of the proposed system.

Wind energy an unimpeded and simply accessible renewable source. It is a more abundant source regardless of the time factor. Further, the capability of wind in producing energy as a green source makes it a favorite for renewable power generation. Wind energy can be exploited for producing power in a fresh environment. The number of unconventional power generation resources is steadily increasing. In this review, we looked at the efficiency of wind turbines in comparison with solar energy, as well as the possibility of combining the two as a hybrid power source. The literature expressed that the power production using renewable sources are being seasonally successful. So, we analyzed the performance of hybrid renewable power generation as a source for future development.

Rise and instability in fuel prices and growing environmental concerns have promoted the scope for alternate to diesel fuel. Vegetable oils or their transesterified forms are used in the diesel engine after blending with various petroleum fuels. Waste vegetable oil (WVO), a known problematic liquid waste, holds potential in this regard. However, WVO is associated with the problem of higher viscosity and lower calorific value. The present work proposes to overcome such limitations by blending with diesel and kerosene. Three blends with varying volumes of WVO in diesel as well as kerosene were prepared. Physical properties of the blends showed similarity with that of diesel fuel and conformed to diesel standards. The various WVO blends showed acceptable engine performance and emission. WVO-kerosene blends recorded lower BSFC and higher BTE than diesel-kerosene blends. WVO-kerosene blends resulted in lower CO and HC emissions than diesel. A rise in the NOx emission with the addition of WVO in the fossil fuels was recorded. Blending WVO with fossil fuels reduced the overall fuel price. WVO-kerosene blends can cause 22–40% reduction in overall price as compared to similar WVO-diesel blends.

Biodiesel are produced from plant derivatives and are highly potent in usage instead of diesel in diesel engines due to their low emissions which significantly reduce the environmental impacts and can use as fuel for diesel engines deprived of any alterations. The major drawback of biodiesel is associated with NOx and smoke reduction. Emulsified fuels are known to have high potent in reducing harmful emissions into atmosphere. Nitrogen oxides (NOx) and smoke are the major pollutants released through diesel combustion. Using water emulsions in biodiesel reduces the nitrogen oxide and smoke emissions. Span 80 is used as surfactant during emulsion to stabilise the whole blend. Nanoparticles increases the combustion rate and provides the combustion stability. Water is mixed with biodiesel in different proportions to study the emulsion stability, characteristics and performance. Water in biodiesel emulsion contains water range of about 5–15%. By literature survey and experimental analysis, we found that 5% water emulsion in biodiesel blend.

The present study experimentally investigates the combustion characteristics of a multi-cylinder MPFI spark ignition engine fuelled by gasoline under uniform magnetic fields. Permanent magnets made of N38 grade NdFeB are used to magnetize the liquid phase hydrocarbons and the impact produced on combustion characteristics like in-cylinder pressure and net heat release rate are studied under different speeds and load conditions of the engine operation. Three different magnetic intensities (3200 G, 4800 G, and 6400 G) are employed in two different magnetization patterns (axial and radial) at an inbuilt ignition timing of 5 deg bTDC. Magnetic field assisted combustion is observed to enhance the performance characteristics of the engine, while simultaneously reducing the exhaust emissions to a significant level. A statistical analysis of cyclic fluctuations in magnetic field-assisted combustion is also made which shows a reduction in fluctuations (COV) with the application of each stage of ionization. The increase observed in peak pressures and heat release rates along throughout the combustion cycles with reduction in cyclic variations indicate that magnetic field-assisted combustion exhibits better combustion characteristics as compared to normal gasoline combustion.

With the rising population day-to-day there is surge in number of automobiles in the world. The huge increase in quantity of vehicles on track more demand for fuel. The widespread use of petrol and diesel leads to unadorned environmental problems like global warming, emissions of greenhouse gases, and reduction in their levels. Due to more demand and usage of fuels, stringent emission norms there is a need for development of renewable fuel. Engine vibration is higher in diesel engines, resulting in a shorter engine life cycle. Using a single cylinder compression ignition engine, an experimental study was conducted to measure combustion, noise, and vibration properties, as well as their similarities. The tests were conducted without maximum charge, using Linseed biodiesel, 10% and 20% (v/v) Linseed mix and baseline-mineral diesel. Samples of engine combustion noise were used with a microphone. In 3 direction measurements of motor acceleration, a triaxial accelerometer is utilized: vertical, lateral, and longitudinal. NI LabVIEW is used to collect data and perform research. Within the range of 0–100 Hz and three ways, higher peak amplitudes are observed for both diesel and linseed biodiesel at the frequency of 25 Hz. The highest level of combustion noise was observed with a 20% biodiesel mix, related to a longer delay in ignition and an increased rate of heat release. These findings were supported by other observations concerning combustion noise, ignition delay, and heat release rates.

In recent times, with more thermal efficiency, low NOx and particulate matter, Homogeneous Charge Compression Engines (HCCI Engines) emerged for renewed interest. However, knocking and misfiring were considered as classic problems in HCCI engines. To compensate the impact of depletion of petroleum reserves also to lessen the deleterious effects of most regularly used fossil fuels, alternate fuels emerged into the scenario. Researchers studied that Compression ignition engines faced difficulties due to the inherent nature of high viscosity, when vegetable oils were consumed. In the present research, the impact of Kusum oil biodiesel blends on performance and emission characteristics were examined using experimental investigation. Conventional diesel engine has been converted into HCCI engine to operate in homogeneous mode. The blends B20, B50 and pure biodiesel were taken, by varying the input air temperature and port fuel injection pressure, the variation of performance and emission characteristics were analyzed. To implement HCCI mode operation, Homogenous mixture of air and fuel is made by port fuel injection technique which is the basic requirement. Using an external device, the mixture formation and fuel vaporization was done. Varying the temperature of the blends at different port fuel injection pressures, the performance parameter brakes thermal efficiency, NOx, CO, CO2, HC emissions and smoke density were analyzed in the HCCI mode. Also optimal parameters were found by using the experimental investigations.

This work discusses the load frequency control of a three-area interconnected power system regulated employing a PID controller whose gain parameters are tuned using one of the optimization algorithms instigated and inspired by smart foraging or searching deportment of honey bees. The three-area power system depicted is assembled in such a way that the area-1 consists of a non-reheated turbine, area-2 consists of a reheated turbine while the third area consists of a combination of both non-reheated and reheated turbine units as the power consumed is profoundly generated by thermal power plants across the world and they exist to a greater degree. All the existing areas are equipped with PID controllers, and the objective function taken into account is Integral Time Absolute Error (ITAE). To subdue all the fluctuations attributed to the perturbations in the system and reacquire the frequency to the nominal quantity swiftly is primary intent of this work. The performance of the controller is simulated in the MATLAB/ SIMULINK version. The results depicted the swift settling down of the frequency deviations with minimum steady state error.

A high-gain non-isolated DC–DC PWM boost converter of two-level output voltage is discussed. In traditional step-up converter like, transformerless converters using switched capacitor, switched inductor, etc., maximum voltage gain is not satisfied our expectations because of maximum duty cycle (i.e. duty cycle closely one). Switches are facing severe problem in reverse recovery, high on-state losses, high electromagnetic interference (EMI), etc., when they are operating at extreme duty cycle. Generally, grids are interconnected with AC supply from various power stations. But increase in solar energy demands the use of grid for DC supply. Nowadays, DC micro-grid is having higher attention due to rise in load requirement in DC and betterment in power quality. Based on power rating, these DC loads need various output voltages. In DC micro-grid, photovoltaic source (PV) is the best source of energy. The purpose of non-isolated converters is low cost and high reliability. A high-gain converter with PWM control is an essential for DC micro-grid due to very minimum voltage from photovoltaic. To achieve this, a boost DC–DC PWM converter configuration is discussed that exhibits a maximum voltage gain behaviour and the switches are controlled by a single control signal, which simplifies the operation. The new converter functions in uninterrupted output current mode.

The unceasing efforts to design an optimal controller in automatic generation control (AGC) of electrical power system motivate the design of a Two-Degree-of-Freedom Fractional Order PID (2DOF-FOPID) controller. Two-area interconnected reheat thermal and hydro including boiler dynamics and dead zone nonlinearity in each area is tested using the designed controller. The performance of the proposed controller is studied with the conventional PID controller and classical Two-Degree-of-Freedom PID (2DOF-PID) controller. The elemental intension of designing supplementary controllers aims to diminish the area control error (ACE). A new crow search algorithm (CSA) is chosen to evaluate the suitable values of controller gain parameters in order to curtail the figure of demerit (ITAE). The transient response of the system is investigated pertaining to 0. 01 p.u. load disturbance in area-1. Investigations reveal that the transient response is superior using the 2DOF-FOPID concerning the stability indices, viz. overshoot (Osh), undershoot (Ush) and settling time response of the power system.

In this work, an adequate approach is depicted to endorse the superiority of cascade PI-fractional order PID (PI-FOPID) controller over PID and FOPID controllers and also to validate the quasi-oppositional-based crow search algorithm (QOCSA) to elect the peerless gains of the controllers over CSA algorithm. PI-FOPID controller is implemented in an interconnected reheat-thermal power system to amend system performances. The system is designed with nonlinearity such as generation rate constraint (GRC) and ITAE as fitness function. The fundamental intention of this system is to diminish the divergence of frequency and power. For this purpose, a hybrid QOCSA and CSA algorithms are implemented to determine the significant parameters of controllers by which the divergence reducing competence of controller can be improved. This analysis to substantiate the proposed PI-FOPID controller and QOCSA algorithm is accomplished with a step load of 0.01 p.u. injected in area-1. Finally, QOCSA is substantiated over CSA algorithm, and PI-FOPID controller is confirmed as an excel controller over FOPID and PID controllers.

Since from the last decade, there is increase in the operation of renewable-based hybrid power system for the power generation purpose, which may cause frequency-related problem due to the use of small capacity synchronous and induction generator, which offers lesser inertia. To deal with these problems, a linearized model of wind and small hydrosystem with frequency controller loop has been developed for an isolated system. The controller used in the system, not only improves the transient response of the generation but also deals with the load uncertainty. The controller parameter has been optimized by particle swarm optimization (PSO) technique to provide the proper coordination between the wind and small hydrosystems to improve the output frequency response.

In a power system, the load differs continuously. As a result, frequency also differs continually. Automatic generation control (AGC) has a crucial role in the entire power system network, which is used to control the changes in scheduled tie-line powers by maintaining rated frequency within tolerable limits. Basic load frequency control (LFC) with only primary controllers like governors may or may not satisfy the power system constraints due to steady-state errors and sluggish response. Unsatisfactory secondary controllers also may result in power blackouts. To get good transient and steady-state responses, different secondary controllers like proportional, integral, and derivative (PID), active disturbance rejection controller (ADRC), and PI-PD controllers are used for the real three area power system (IEEE paper) with reheat and non-reheat thermal plants. Here the method of particle swarm optimization is used for tuning the PID and PI-PD controllers. The resulting power systems are simulated and analyzed using MATLAB/Simulink software to present a better secondary controller.

The scope of the current study is to estimate the flow fields in reacting and non-reacting flow regimes of a solid-propellant ducted rocket combustor (SDRC) at different ram duct angles. The 2D simulation and combustion modelling of the reacting and non-reacting flow were carried out using OpenFOAM. The flow fields and the mass fraction distribution were computationally modelled and qualitatively compared. The predicted axial and vertical flow velocities were compared with the experimental and analytical results from the literature to validate the current study at different ram duct angles. The performance in terms of flow velocity and mass fraction was found out to be the highest in the 45° configuration.

The paper addresses the computational fluid dynamics solution for safe separation of sabot from the penetrator in armour piercing fin stabilised discarding sabot. The design and functional characteristics of sabot are modelled to achieve a safe trajectory. Driving bands are important components of APFSDS which adds the sabot together to efficiently transfer the gas forces on penetrator. Sabot, penetrator, fins, and driving bands are modelled separately which further assembled together using solid works CAD software. All tri-element is used to generate the unstructured surface mesh of the model using ICEM software. The aerodynamic coefficients of lift, drag, and moment acting on the penetrator and sabot discard process are evaluated by using in house developed finite volume-based implicit solver. The discarding process of sabot generates shocks at supersonic speed which can affect the trajectory of the penetrator during flight. The timely breaking of bands, after muzzle exit, the APFSDS is an important phenomenon to simulate and govern safe separation of sabots. Based on finite element method software, the breaking of bands was simulated to find the stress and deformation under pressure force exerted on sabot cups. The pressure exerted on sabot cups and separation of sabot due to aerodynamic forces were simulated using in house developed finite volume-based implicit CFD solver. The Cl, Cd, and pitch moment are plotted against the angle of sabot with penetrator which clearly indicates the uniform separation of the sabot.

Penetration of renewable energy sources has become an important matter due to rapid diminishing of conventional sources. Environmental pollution is also one of the main reasons in many countries. Virtual power plant (VPP) is a new technology which can manage the uncertainties caused by the renewable sources in demand side. VPP will aggregate the capacities of distributed energy resources (DERs) to create a single operating profile. Each DER will get visibility and controllability in the electricity market with this technique. In this paper, virtual power plant concept is demonstrated and the bidding strategies of energy among VPP and grid are developed for four different scenarios. A model is considered for the analysis of the system which consists of two solar power generation units and one wind power generation unit with energy storage system (ESS).

Soft landings on extra-terrestrial surfaces are vital for any sample return missions. Moreover, during landing on such bodies, dust impingement on the lander module and Extra-Vehicular Activity (EVA) systems can cause serious complications. To prevent system failures due to scoured regolith, and also minimize contamination of surface regolith for sample collection, the rocket can be used to decelerate the spacecraft to a vertical descent velocity from which it can freefall. A Direct Simulation Monte Carlo (DSMC) technique is developed to investigate the interaction of rocket plume with surface regolith of an airless extra-terrestrial body. Continuum breaks down as the exhaust exits the engine nozzle, and the gases expand rapidly into the vacuum. Near the nozzle exit, the process enters a rarefied flow regime and an open-source DSMC code is developed to model the movement and collision stages of rarefied plume gas and dust particles. In this simulation, the collision occurs between gas particles of the rocket plume as it impinges on such an extra-terrestrial surface. The solver used for carried out this simulation is dsmcFOAM solver, a part of OpenFOAM. The surface properties such as pressure coefficient and heat flux are computed and analysed to observe the impact of plume impingement on extra-terrestrial regolith.

The aim of this study is to evaluate the performance of the shock tube with argon and carbon dioxide as working fluid using unsteady numerical simulations. A two-dimensional axisymmetric model of a shock tube is taken for the study. Simulations were carried out for different diaphragm ratios to study the dependency on temperature behind the incident shock wave, shock Mach number and temperature behind the reflected shock wave. Time-dependent flow is necessary to understand the properties of gas behind the shock. Effects of viscosity are neglected to reduce the computation times for highly non-uniform processes. For an inviscid flow, Navier–Stokes equation is reduced to the Euler equation. Adaptive mesh refinement (AMR) technique was used to correctly resolve and capture shock waves and contact surface. Different gas combinations of argon and carbon dioxide were taken in driver/driven regions for the simulation. The different driver/driven gas model shows an advantage in shock Mach number of 4.7% at lower diaphragm pressure ratios and significant changes in temperature of shocked gas and temperature behind reflected shocks wave are also.

Modeling and simulation helps in acquiring successful results of any process. Energy assessment is one of the important studies of process equipment. To intensify the process results multistage design was implemented in continuous medium dryer. In this study, simulations were carried with multistage fluidized bed dryer using Aspen Plus Simulator by changing the values of air temperature from 40 to 80 °C and flow rate of air from 40 to 80 kg/h(Rate of solids flow -10 kg/h and feed moisture percentage -10%). The final moisture content, exergy efficiency and exergy loss of multistage fluidized dryer model were analyzed. From simulation results, the exergy efficiency obtained is in the range 0.07–0.73 for the multistage dryer. Comparison with single stage dryer is reported. The experiments were conducted on multistage fluidized bed dryer to validate the simulation results. The simulation results have shown good agreement with experimental results.

This study employs a four-stroke gasoline engine with water cooling. Trials are being conducted to determine if the exhaust gas calorimeter model can be used to measure heat losses incurred by exhaust gas. The model took into account calorimeter system elements such as the water reservoir, inlet and outlet tubing, as well as cold and hot fluids. If the engine speed increases, the throttle can open wider, allowing more air to enter the cylinder during combustion. As a result, the fuel mass will increase, influencing the exhaust gas temperature. Investigate the rate of heat losses from exhaust gas using an exhaust gas calorimeter. A heat exchanger is a piece of equipment that is intended to efficiently transfer heat from one medium to another. Computational fluid dynamics (CFD) is a simulation methodology that employs powerful computers and applied mathematics to simulate fluid flow situations in order to estimate heat, mass, and momentum transfer and to optimise architecture.

Abrasive jet machining process is finding great importance in engineering applications. It is a machining process, where removal of material happens due to erosion effect by passing a high velocity stream of abrasive particles along with a gas medium. A nozzle is used to supply the jet of abrasive particles with air at a very high velocity. The conventional nozzle presently used for the process gives low velocity and results in lower material removal rate (MRR). In this work, three different types of convergent nozzles, (i) Geometry type-I (25 mm length), (ii) Geometry type-II (50 mm length), and (iii) Geometry type-III (newly designed nozzle), have been designed and analyzed using CFD. Multistart thread is employed in all the three types of the nozzle for improving the velocity and flow rate of the mixture of air and abrasive particle. Ansys Fluent 16.0 tool is used for computational fluid dynamics analysis. The velocity of the mixture from nozzles with thread was analyzed. Velocity, pressure, and angular velocity of mixture inside the nozzle were compared. The results showed improvement in newly designed nozzle, and the velocity was 42.84 m/s. The rate of flow obtained through the newly designed nozzle is high compared with other conventional types of nozzles.

Over the years, many developments have been encountered in both offshore and onshore wind turbine blade design. In this study, the aerodynamic effect of vortex generators in WindPACT 1.5 MW wind turbine blade is made by NREL. The turbine contains three types of airfoils, i.e., S818+, S825+, and S826+ which are developed by NREL. Vortex generator (VG) is attached with the wind turbine along throughout length of blade. Geometry was created in solid works software and meshed using a fluent watertight meshing workflow for better accuracy, the full-scale wind turbine CFD (computational fluid dynamics) analysis was done with ANSYS fluent solver, and series of computation was done to validate. The flow in the wind turbine with and without vortex indicator has been visualized. The aerodynamic structural effects and pressure distribution along the surface of the blade and their impact on the strength of the blade were studied. The results indicate that the vortex generators along the length of the blade reduce the flow separation over the blade surface and also maintain the pressure difference that causes the deformation of the blade.

The aim of this paper is to design the intake system for an engine to optimize the performance of restricted KTM 390-supported powertrains of a Formula Society of Automotive Engineers (FSAE) combustion car of team Camber Racing. Keeping in a view the safety of students, power produced by the engine is restricted by inclusion of a 20 mm air restrictor. It is made mandatory for all the student teams to participate in the racing event. With a goal of exploring and understanding various parameters involved in modeling a 20 mm air restrictor which is to be incorporated in the intake of 390 cc KTM single-cylinder engine, the required engine performance need to be attained. Analysis is done with the help of the CFD software ANSYS Fluent. With the incorporation of air restrictor upstream the intake system, pressure loss is observed. This in turn reduces the volumetric efficiency of the engine significantly. The goal of the intake system was to reduce the pressure loss caused due to restriction and to provide a reservoir to act as an infinitely large reservoir of air, to improve the breathing characteristics of engine (Hadjkacem et al., Arab J Sci Eng 2018). The constraint was engine response delay. The volumetric efficiency could have been further improved but would have been detrimental to engine response time (Mattarelli and Rinaldini in SAE Technical Paper 01-0833:2012, 2012 [1]).

In this paper, we report on the development and the implementation of the mesoscopic approach based on the Lattice Boltzmann method (LBM) in order to simulate three-dimensional coupled modes of thermal and fluid flows. First the lattice Boltzmann method (LBM) has been used to solve transient heat conduction problems in 3D Cartesian geometries. To study the suitability of the LBM, the problem has also been extended to deal with a coupled conduction-radiation heat transfer problem in a three-dimensional cavity containing an absorbing, emitting, and scattering medium. In this case, the radiative information is obtained by solving the radiative transfer equation (RTE) using the control volume finite element method (CVFEM). Second, a 3D incompressible thermal lattice Boltzmann model is proposed to solve 3D incompressible thermal flow problems. A D3Q19 particle velocity model is incorporated in our thermal model where the density, velocity, and temperature fields are calculated using the two double population lattice Boltzmann equation (LBE). It is indicated that the present thermal model is simple and easy for implementation. It is validated by its application to simulate the 3D natural convection of fluid in a cubical enclosure, which is heated differentially at two vertical side walls. In order to test the efficiency of the developed method, comparisons are made for the effect of Rayleigh number on the temperature and velocity distributions in the medium. Validation and the analysis of numerical results of flow and thermal fields in the cubic cavity are at Rayleigh numbers of 103–106. In all studied cases, it is found that the numerical results agree well with the results reported in previous studies. The 3D LBGK algorithm presented here can also be extended for a convective radiative problem in a three-dimensional grey participating medium in the presence of computers with sufficient memory and computational power to perform well-resolved calculations of the hybrid 3D-proposed model.

Downbursts are extremely spontaneous and dangerous phenomena that have been shown to be responsible for failures of many structural systems. The Wall of Wind team is currently in the process of developing a large-scale downburst simulator that could facilitate research to improve the resistance of building envelopes and lifeline infrastructures. For this purpose, four setups have been numerically simulated in order to recreate downburst-like wind characteristics while the height of the maximum velocity can be controlled. Consequently, three different roughness elements have been added, and the results demonstrate that the roughness elements have a positive impact on the height of the maximum velocities.

Computational Fluid Dynamics, CFD, has evolved from a scientific interest to a practical engineering tool that can assist engineers in the design and optimization of equipment of different types and for different applications. The present work introduces two case studies where CFD analyses are employed as a tool for design evaluation and optimization. These include the case of designing dust extraction devices for the wood industry and the case of improving the uniformity of the air inlet velocity distribution in a convective dryer. The methodologies and typical results are presented in each studied case. The importance of the simulations in the design and optimization was demonstrated as they allowed the calculation of the equipment behavior in situations that are otherwise hard to foresee, either because of the unpredictable combined effects of different features or because of the counterintuitive results.

An air conditioning system was built in all deluxe vehicles. The air conditioning fit in vehicles will give higher fuel consumption because of power absorbed to run the compressor from engine output. The main drawback of reduction in mileage will be improved in this study by increasing the heat removal rate, thereby decreasing the compressor power absorption. This study was depicted with experimental test rig consists of various components such as compressor, condenser, evaporator, expansion device, and electric motor were put together. The modifications were made on the existing system viz., the compressor was run by an electric motor instead of engine power. Inbuilt condenser fan was replaced by an evaporative cooling method using exhaust fan was surrounded by a cooling pad. Cool water is supplied to the cooling pad using a pump. The test was conducted on conventional cooling and evaporative cooling methods to obtain a similar cooling effect. The result showed that a higher coefficient of performance (COP) for the evaporative cooling system compared to the conventional system due to an increase in heat removal rate.

In present study, a comparative thermodynamic assessment of a solar-driven organic Rankine cycle integrated with an absorption refrigeration system was performed. During the analyses, parabolic trough solar collectors were used to meet the necessary thermal energy for the power and refrigeration cycles. For the absorption refrigeration, the H2O-LiBr cycle was proposed for the integrated system in order to maintain chilled water. The analysis was carried out for three supercritical working fluids: carbon dioxide (R744), ethane (R170), and fluoromethane (R41). For specified parabolic trough collector parameters, energetic and exergetic performances of the cycles were determined for constant turbine inlet pressure and constant pressure ratio. A parametrical study was also implemented for determining the effect of the system parameters on cycle performances. According to the results, the best performance was achieved using R41 with a net energy production rate of 32.54 kW, followed by R170 and R744. Based on the results of the exergy analysis, the leading exergy destruction rate was estimated for the integrated cycle working with R744. Additionally, the necessary collector length and area were determined for specific net power generation and refrigeration duties.

In this paper, an attempt has been made to carry out thermodynamic investigation of an integrated organic Rankine cycle for waste heat recovery from a vapor compression refrigeration cycle (VCRC). The heat rejected by the vapor compression cycle is utilized and converted into electrical energy by running an organic Rankine cycle (ORC). A sharing heat exchanger (SHX) is used to transfer the heat from VCRC to the ORC. It works as the condenser in VCRC as well as the evaporator in ORC. Six refrigerants are selected as the working fluids for the refrigeration subsystem, which are R134a, R407C, R404A, R407C, R600a, and R410A. Four different working fluids (R123, R227ea, R600, and R245fa) are chosen as the candidates for the ORC subsystem. Coefficient of performance (COP), the energy output, and the thermal efficiency of the combined arrangement consisting of ORC and VCRC are considered as main performance parameters for this numerical work. For the present investigation, total of 24 working fluid combinations are considered, and the system performances with these combinations are analyzed and compared. Results show that the maximum COP of about nearly 3.5 is obtained when R134a is taken as the working fluid in the VCR cycle, and R600 is taken as the working fluid in the ORC. The maximum thermal efficiency and the maximum energy output are obtained when R123 and R245fa are used as working fluid in the ORC, respectively. The corresponding values are 3.1% and 3.5 kW for a 10-ton capacity refrigeration plant.

The energy efficiency of buildings is highly affected by heating, ventilation, and air-conditioning (HVAC) systems being more energy intensive. The paper aims in providing an energy-efficient cooling solution by analyzing and modeling the cooling load requirement of a commercial building and optimizing the chiller system. Design Builder software integrated with Energy plus simulation software is used for predicting the scope of improvement by energy simulation modeling. The study also focuses on analyzing the performance improvement achieved with the optimized chiller system and by integrating it with efficient control strategies at the component level. With the energy-efficient optimization, along with the assessment of energy cost savings, the reduction in carbon emissions is also interpreted. About 50% energy savings is achieved with the water-cooled chiller retrofit, and with improved control strategies, energy consumption is reduced by 62%. An added advantage of reduced energy consumption is the reduction in carbon footprint, which is analyzed in the study. This reduction contributes to the global aim of reducing carbon dioxide emissions and controlling global warming.

Energy is the ability to cause a change in a system. It is usually available as exergy and anergy. Exergy is a useful part of energy, also known as available energy. Anergy is the counterpart of exergy, also known as unavailable energy. Thermodynamics is the science associated with energy and exergy, thereby ensuring both laws of thermodynamics—the first and the second by incorporating energy and exergy efficiencies. Refrigeration is a technology to preserve commodities at lower temperatures than their surroundings. One of the most widely used refrigeration systems is a vapour compression refrigeration system whose basic objective is to produce a refrigerating effect at the desired location. Commercial large capacity plants consist of the preservation of a different variety of food items requiring different preservation temperatures. It needs to maintain the evaporators correspondingly at different required temperatures. It requires multi-staging in compressors to save the compressor energy consumption. Exergy efficiency governs the actual performance of the system by knowing its deviation from the ideal one, and thus, is a true measure of any system performance. In this paper, an exergetic investigation of a multistage multi-evaporator vapour compression refrigeration system with individual expansion valves using R22 refrigerant is carried out. A shell and helical type heat exchanger is inbuilt as an intercooler between two compression stages comprises of refrigerant on both—shell and tube side. The two evaporators are maintained at −10 °C and 10 °C. Various parameters like exergy destruction and exergy efficiency are computed. Compressor consumes the maximum exergy destruction among all the components. Variation of exergy efficiency with different parameters is represented in graphical forms. Exergy analysis is a well-known technique and proved to be an alone tool for evaluating and comparing systems more meaningfully. It also helps to improve and optimize the design and analysis of a system.

Freeze drying is an advanced dehydration technology with many advantages over other traditional drying methods. The present work deals with development of an experimental model for freeze drying. The sample products used were skimmed milk and egg white. Experiments were performed with skimmed milk and egg white to estimate the transient moisture content. The experiments were performed with a laboratory lyophilizer setup and deep freezing was performed using a domestic refrigerator. The milk lost its 50% mass during the first 2.5 h freeze-drying process. It took 12 h to reach its solid powdered state. The egg white lost its mass very vigorously in the first 6 h of drying, and after that, a constant drying rate was noticed. The constant drying time continued up to 10 h. The egg white reached its solid state at 10 h. The obtained results were compared with existing numerical study, and a reasonable match was observed.