Ali M.Nikbakht

• Professor, PhD
• Researcher-Professor (Full)-Mechanical Engineering at Queensland University of Technology

This study deals with artificial neural network (ANN) modeling of a diesel engine using waste cooking biodiesel fuel to predict the brake power, torque, specific fuel consumption and exhaust emissions of the engine. To acquire data for training and testing the proposed ANN, a two cylinders, four-stroke diesel engine was fuelled with waste vegetable...

The objective of this study was to investigate dehydration kinetics of barberry (Berberis Vulgaris) at different drying temperatures (60 ̊C, 70 ̊C, 80 ̊C), air velocities (0.3 m/s, 0.5 m/s, 1 m/s) with two types of pretreatment. Drying time and colour quality during dehydration were experimentally determined. Barberries were dried from the initial...

This study deals with artificial neural network (ANN) modeling of a spark ignition engine to predict the engine brake power, output torque and exhaust emissions (CO, CO2, NOx and HC) of the engine. To acquire data for training and testing of the proposed ANN, a four-cylinder, four-stroke test engine was fuelled with ethanol-gasoline blended fuels w...

Conventional plant available water (PAW), least limiting water range (LLWR), integral water capacity (IWC) and integral energy (EI) are different approaches to quantify the soil water availability for plants. The PAW, the soil water between field capacity (FC) and permanent wilting point (PWP), is based merely on the soil matric potential. The LLWR...

The main purpose of this research is thermal modeling of a typical Flat Plate Solar Air Heater (FPSAH) in Urmia climate all the year around in 2009, in which must be used for agro-food industrial consumption. Urmia climate condition in 2009 was selected as work condition of FPSAH in modeling. The real and hourly data of ambient temperature and sola...

Heat losses from the utilities are inevitable in industries which utilize heat in unit operations. Sugar processing plants are among the industries where energy is a considerable share of final product. Accurate thermodynamic and economic analyses in sugar industry depend strictly on estimation of heat losses from the surfaces of utilities. In this...

Concentrate industry is a major section in agro-industry dealing with massive consumption of energy. An extensive research was done in this study on the energetic, exergetic and exergoeconomic (3E) assessment of steam generation unit and evaporation line in the sour cherry concentration plant. Along with thermodynamic inefficiencies, precise costs...

In this study, inclined broken roughness is experimentally investigated to enhance the thermohydraulic performance of solar air heaters. Current article focuses on a fuzzy-based structure as a substitution method for predicting the thermohydraulic performance. A separated fuzzy inference system for each smooth and roughened plate along with an inte...

This study was carried out to optimize a computational model of a new underground passive solar greenhouse to improve thermal performance, storage, and saving of heat solar energy. Optimized and conventional passive solar greenhouse were compared in regards of indoor air temperature, irradiation, and energy demand. Six different materials were used...

In this study, evaporation line and steam and power production unit in a sugar processing plant were investigated by means of energetic, exergetic, and exergoeconomic (3E) analyses. 3E parameters for each subsystem in both units were computed via coding in EES software. For a more detailed analysis, the heat losses from the surfaces of the subsyste...

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 crystal...

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, Iran Material and methods: Precise and instrumented experimentation has been conducted to calibrate the computational fluid dynamics (...

The major drawback of microwave drying is non-uniform heating which may result in low quality dried products. To monitor the electromagnetic field distribution, a simulation process using Finite Element Methods was conducted. Three geometries in different sizes were selected as the microwave cavity. Analysis of variance for the non-uniform heating...

To improve the thermal performance, storage and saving heat solar energy of conventional greenhouse, a passive solar greenhouse was built which its north wall was made of soil. The bottom part of the north, south, west and east walls were sloping and constructed below ground surface. The indoor air temperature was measured during January and Februa...

To improve the thermal performance, storage and saving heat solar energy of conventional greenhouse, a passive solar greenhouse was built which its north wall was made of soil. The bottom part of the north, south, west and east walls were sloping and constructed below ground surface. The indoor air temperature was measured during January and Februa...

In this paper the energy and exergy analysis of flat plate solar collector simulator equipped with Inclined Broken Rib roughness is based on experimental data in open circuit as well as optimizing system operating conditions was investigated. The experiments were carried out with nine levels of mass flow rates (0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0...

In this paper the energy and exergy analysis of flat plate solar collector simulator equipped with Inclined Broken Rib roughness is based on experimental data in open circuit as well as optimizing system operating conditions was investigated. The experiments were carried out with nine levels of mass flow rates (0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0...

Introduction Steam generation system is a crucial and essential part of food industries which generates and distributes steam for consumption in domestic production units. Energy analysis based on the first law of thermodynamics was employed as the basic approach to assess energy systems. However, the energy approach does not provide information on...

Drying systems are widely used in food processing industries. There exist serious complications in their design and operation since the target is to minimize cost and energy while to increase efficiency and quality. Novel methods have been introduced to comply with such demand among which microwave technology is highlighted in the last decade. It i...

The artificial neural network was applied to map the thermohydraulic performance criteria of the solar air heater with constant values of geometric parameters. Along with intelligent prediction of friction factor and Nusselt number, the main idea behind the research was modeling the performance of solar air heater through the temperature and veloci...

Energy survey is always a critical stage of the management in the process engineering facilities. As the first and crucial step toward technical, thermo engineering and economic improvement and optimization of sugar production process, energy audit is conducted experimentally and analytically in the evaporation line of Urmia sugar factory. To yield...

Thermo-compressors are used to compress secondary fluid. The simplicity no moving part is one of its advantages over mechanical compressors. The thermo-compressor performs compress by the convergent-divergent section. Comprehensive understanding of operation inside the thermo-compressor is extremely useful for practical applications. The phenomena...

There is a growing recognition of the fact that solar energy utilization plans cannot be carried out without explicitly accounting for the uncertainty presented in the received solar irradiation. This may be expressed as an uncertainty quantification problem. A novel stochastic energy analysis is introduced to study the transient heat transfer prob...

Computational fluid dynamics (CFD) is a numerical technique for the solution of the equations governing the flow of fluids inside a defined flow geometry. CFD has been applied extensively to great benefit in the many different processing industries. Its numerous applications include: predicting the gas flow pattern and particle histories, such as t...

Experimental analysis of air velocity and temperature distribution in poultry houses is laborious, especially for large scale houses. Enhanced broiler yield can be obtained when the house is suitably ventilated. Therefore, efficient prediction tools would be vital. Computational fluid dynamics (CFD) provides detailed data on indoor flow patterns, a...

High energy and time consumption in the dehydration of sugar cubes hinder its industrial commercialization. Microwave is employed to overcome the drawbacks of hot air drying. For microwave power 880 W, pulsing ratios 1.5, 2.5, 4.5, and 10 were applied to prevent thermal runaway and probable melting and caramelization. In order to monitor the spatia...

Finite element numerical solution was employed to solve coupled model of electromagnetic, heat and mass transfer phenomena in microwave dehydration of sugar cube. For microwave power 880 W, pulsing ratios 1.5, 2.5, 4.5 and 10 were applied to prevent thermal runaway. Color quality of dried sugar cubes was assessed by calculating whiteness, yellownes...

The global trends indicate a growing commitment to renewable energy development because of declining fossil fuels and environmental threats. Moreover, the global demographic growth coupled with rising demands for food has escalated the rate of energy consumption in food section. This study aims to investigate the techno-economic impacts of a grid-c...

A new triaxial dynamometer was designed, constructed and tested to measure and locate the position of all forces and moments on tillage implements, up to a maximum force of 10 kN and a maximum moment of 10 kN × m. The design concept of the facility was based on four frames attached to each other by load cells and tillage tool were attached on the i...

This study presents a mathematical modeling of eggplant slice drying process in a continuous band dryer. The experiments for drying of eggplant slices were conducted at three air temperature levels of 45, 60, and 75 °C, inlet air velocities of 1, 1.5, and 2 m/s, and belt linear speeds of 2.5, 6.5, and 10.5 mm/s. To estimate the drying kinetics of e...

This work aimed to investigate the drying behavior of melon seed during combined fluidized bed-microwave drying system. Three drying air temperatures (40, 55 and 70 °C), three microwave powers (270, 450 and 630 W) and three air velocities (0.8, 1.5 and 2.3 m/s) were tested. Five mathematical models were selected to fit the experimental data for dry...

A new design of solar air heater simulator is presented to comply with the extensive applications inagro-industry. A wise installation of increased heat transfer surface area provided uniform and efficient heat diffusion over the duct. Nusselt number and friction factor have been investigated based on the constant roughness parameters such as relat...

On-farm detailed electric load profile is becoming increasingly important in the context of renewable energy source implementation in livestock housing due to rising energy costs along with concerns over greenhouse gas emissions. This study aimed to propose and investigate a pragmatic methodology to determine detailed energy demand profile in dairy...

On-farm detailed electric load profile is becoming increasingly important in the context of renewable energy source implementation in livestock housing due of rising energy costs along with concerns over greenhouse gas emissions. This study aimed to propose and investigate a pragmatic methodology to determine detailed energy demand profile in dairy...

Artificial neural network was applied to map the thermohydraulic performance criteria of the solar air heater with constant values of geometric parameters. Along with intelligent prediction of friction factor and Nusselt number, the main idea behind the research was modeling the performance of solar air heater through the temperature and velocity f...

The purposes of this article are studying the effects of oxygen presence on waste wood pyrolysis process in order to produce bio-char. To reach the goal, cubic samples of size 2.5 cm pyrolized at 300 and 400 °C. The surface and center temperatures of samples were measured and their mass losses were calculated from the ratio of pyrolized mass to ini...

The main incentive in processing fruits such as apple is reduction of losses and gaining added value. In this research, drying kinetics and drying efficiency of Golden Delicious apple slices are investigated using hot air flow and uniform microwave drying. Microwave power levels, 500, 1,000, 1,500, and 2,000 W, air temperatures, 40, 50, 60, and 70°...

Ag/bauxite nanocomposites have been prepared using in situ reduction of aqueous AgNO3 solution in a bauxite matrix and investigated for the transesterification of sunflower oil with methanol in order to study their potential as heterogeneous catalysts. The prepared nanocopmosites were characterized by XRD, SEM, EDX, FT-IR, and TG- DTA. The Central...

One of the major problems in the industry of medicinal and aromatic plants (MAPs) is the absence of a quick, easy and inexpensive method for controlling the quality of these plants. Rosa damascena Mill., is an aromatic plant which is cultivated for its high-value essential oil in the world. In this study, essential oils were extracted from nine gen...

Quality control of essential oils is an important topic in industrial processing of medicinal and aromatic plants. In this paper, the performance of Fuzzy Adaptive Resonant Theory Map (ARTMAP) and linear discriminant analysis (LDA) algorithms are compared in the specific task of quality classification of Rosa damascene essential oil samples (one of...

Strategic outlook of apple cultivation and its significant post-processing challenges have been the leading factors for energy and time saving research approaches in apple processing. In this research, apple slices were subjected to hot air flow, microwave radiation and combined microwave-hot air flow drying. Drying time, energy consumption and the...

The amount of free glycerol in the final product of biodiesel is limited by international standards. In the current study, optimized solvent-resistant nanocomposite membranes were prepared using the phase inversion method based on a poly(ether sulfone) (PES) membrane modified by adding different concentrations of functionalized multiwall carbon nan...

Currently, semi-refined and refined vegetable oils are used as a feedstock in biodiesel production. However, criteria such as competition with conventional fossil fuel, economic reasons, shortage supply of food and its social impact on the global scale have somewhat slowed the development of the biodiesel industry. Spent bleaching earth is currentl...

This study deals with numerical modeling and experimental validation of hybrid fluidized bed‐infrared drying of bulk grain. A mathematical model of simultaneous heat and mass transfer for the aforementioned dryer was developed: first single phase model was used to establish heat and mass transfer equations over the fluidized bed, then the effect of...

Energy and mass transfer investigations in thermal processing of fruits serve as a breakthrough in the design and scale up of drying systems. Diffusivity characteristics and specific energy consumption for drying of fig fruit in a laboratory scale microwave dryer were assessed. Several intervals for microwave power intensity including 0.5, 1, 1.5,...

Exergy analysis of a DI diesel engine running on several biodiesel/diesel blends (B5) containing various quantities of expanded polystyrene (EPS) was carried out. Neat diesel and B5 were also investigated during the engine tests. The biodiesel used was produced using waste oil extracted from spend bleaching earth (SBE). The experiments were conduct...

In this work, five different types of calcium oxide-based catalysts supported gold nanoparticles (AuNPs) (named as nanocatalyst), including commercial CaO, egg shell, mussel shell, calcite, and dolomite were prepared and used in biodiesel synthesis. The optimal conditions of transesterification process were observed at 65 �C with a methanol to oil...

Solid woody wastes collected from pruning of municipal trees is a major source for producing energy and added valued materials in countries, though millions of tons of such biomass are feasible. In this study, the pyrolysis of wood collected from pruning of plane tree at different temperatures and different sizes has been investigated. Pyrolysis pr...

This work presents a Computational Fluid Dynamics approach to evaluate the effects of feed diameter on the pressure drop and magnitude velocity in an aerocyclone utilized in feed processing machinery. Traditionally cyclone separators have been used in agro-industry as pre-screening devices to separate coarse suspended particles (diameter> 10 µm) fr...

آلودگی ناشی از زهرابه قارچی آفلاتوکسین به عنوان یک معضل اساسی برای صادرات پسته محسوب می¬شود. با توجه به استقبال روزافزون استفاده از تکنیک¬ طیف‌سنجی رامان در تشخیص و تفکیک مواد مختلف و همچنین مسائل پیش¬روی روش‌های آزمایشگاهی سنجش سم مذکور) مانند هزینه بالا و زمان¬بر بودن(، هدف از این پژوهش بررسی امکان تشخیص و سنجش آفلاتوکسین پسته با تکنیک طيف¬سنجي ر...

Aflatoxins contamination in Pistachio has been known as a serious problem for export market. Considering the difficulties of current experimental techniques for aflatoxins detection in pistachio (complication, time consuming and experience required), Raman spectroscopy combined with linear discriminant analysis technique was used to classify intact...

This work presents a Computational Fluid Dynamics approach to evaluate the effects of feed diameter on the pressure drop and magnitude velocity in an aerocyclone utilized in feed processing machinery. Traditionally cyclone separators have been used in agro-industry as pre-screening devices to separate coarse suspended particles (diameter > 10 mu m)...

هدف از این مطالعه، بررسی سینتیک خشک کردن بذر خربزه و محاسبه ضریب پخش موثر آن با استفاده از ترکیب خشک کن بستر سیال و مایکروویو می باشد. آزمایش خشک کردن تحت سه سطح دمای خشک کن 40، 55 و 70 درجه سلسیوس، سه سطح سرعت هوای ورودی 8/0، 21/1 و 28/2 متر بر ثانیه و سه سطح توان مایکروویو 270، 450 و 630 وات انجام شد. برای توضیح انتقال رطوبت از لایه نازک بذر خربز...

Due to the fast fossil fuel depletion and at the same time global warming phenomenon anticipated for the next coming years, the necessity of developing alternative fuels e.g. biofuels (i.e. bioethanol, biodiesel, biogas and etc.) has turned into an important concern. Recently, the application of the bio-solvency properties of biodiesel for recyclin...

The effect of three irrigation and seven nutrient treatments on physical properties of safflower seeds was investigated. Physical properties of safflower seeds were determined at a moisture content of 7% w. b. The parameters determined at different treatments were: size, geometric mean diameter, sphericity, surface area, mass, volume, bulk and true...

Localization of designing and manufacturing technology of oil extraction devices and integrating them with biodiesel fuel processing systems has the major importance. With manufacturing of oil extraction devices, domestic oil production will increase and therefore an approach to reducing of dependency on oil importing will be created. Therefore, th...

Safflower is a strategic plant regarding to its valuable nutrition value (45% extractable oil) and industrial applications. Due to massive import of oil in the country as well as high potential for safflower cultivation, the production and investigation of safflower oil extrusion has got remarkable importance. Also design of various processing and...

Although biodiesel has been known as an alternative fuel with specific advantages, it has also been investigated as a bio-solvent. In this study, biodiesel was applied as a bio-solvent for expanded polystyrene (EPS) and the kinetics of polymers’ dissolution in biodiesel was also investigated. Physicochemical parameters such as solubility parameters...

A comprehensive investigation of effect of irrigation systems and nutrient treatments on mechanical properties of IL111 varieties of safflower (Carthamus Tinctorius L.) seeds was fulfilled. Rupture force, deformation at rupture point, hardness, energy used for rupture and modulus of elasticity were measured in order to get an exact picture of the p...

Investigation of qualitative indices for the pulsed microwave dried figs (Ficus carica L.) is accomplished through image processing techniques. Three hundred colour pictures of fig fruit before and after drying were prepared in RGB colour space. After converting the RGB colour space into L*a*b* units, colour values in L*a*b* units were analysed bef...

Energy and exergy analyses of thin-layer drying of sour pomegranate arils with microwave treatment were conducted in this research. Three levels of air temperature (50, 60 and 70 °C) and air velocity (0.5, 1 and 1.5 m/s) were tested for evaluation of dryer parameters. Energy utilization and energy utilization ratio increased with time, while exergy...

The massive consumption of energy in the drying industry makes it a matter of challenge regarding economical aspects and limited recourses. Several methods for drying, including hot air convection, vacuum, infrared and hot air convection-infrared technologies, were applied in order to estimate the consumed energy during the drying of mulberry fruit...

The objective of this study was to investigate dehydration kinetics of barberry (Berberis vulgaris L.) at different drying temperatures (60 ºC, 70 ºC, 80 ºC), air velocities (0.3 m s-1, 0.5 m s-1, 1 m s-1) with two types of pretreatment. Drying time and colour quality during dehydration were experimentally determined. Barberries were dried from the...

سوخت دیزل معمولی به‌دلیل ملاحظات زیست محیطی و انتشار مقدار قابل توجه آلاینده دوده مناسب نبوده و توانایی زیادی در رسیدن به استاندارد‌های جدید را ندارند. یکی از راههای مناسب برای رسیدن به این هدف، استفاده از سوخت های جايگزين از جمله بيوديزل به‌جای سوخت دیزل می‌باشد. بیودیزل از منابع بیولوژیکی (روغن‏های گیاهی و حیوانی) تولید می‏شود. بدلیل قیمت بالای ر...

Energy recovery has been found to be a promising approach for disposal of polymer waste such as expanded polystyrene (EPS) which entraps large volume of air. Biodiesel known as an advantageous alternative fuel possesses bio-solvent attributes and is feasible to be used for energy recovery from EPS. In this study, maximum EPS dissolution value in bi...

Biodiesel is known as an alternative and biodegradable fuel and is produced from oil sources of plant or animal origins. The high cost of feedstock used for biodiesel production and the food security issues are among the challenges faced in justifying the economic use of this green fuel. In addition, despite the proved advantages of biodiesel, ther...

Global air pollution is a serious threat caused by excessive use of fossil fuels for transportation. Despite the fact that diesel fuel is a big environmental pollutant as it contains different hydrocarbons, sulphur and crude oil residues, it is yet regarded as a highly critical fuel due to its wide applications. Nowadays, biodiesel as a renewable a...

Diesel fuel is regarded as highly critical fuel in many countries due to its wide applications. Diesel fuel is a big environmental pollutant as it contains different hydrocarbons, sulphur and crude oil residues. Nowadays, biodiesel as a renewable additive are blended with diesel fuel to achieve many advantages such as lower emissions and higher lub...

Biodiesel as an alternative and renewable fuel could be applied in diesel engines in order to reduce air contamination and dependence to fossil fuels. So far, various processes were prepared for biodiesel production, but using transesterification method via base catalyst in batch reactors could result in a reasonable yield of biodiesel. At the pres...

The main objective of this study was to investigate the effects of microwave power intensity and pulsing ratio on drying behavior of fig fruit in a laboratory scale microwave dryer. During experiments, weight and temperature of the samples were recorded at regular intervals (10 s). The results showed that drying time of products increased by approx...

Common drying systems, including hot air convection, infrared, vacuum and IRconvective were employed to investigate and analyze the drying process of mulberry fruits. To evaluate the effect of pretreatment on the drying phenomenon, samples were pretreated by being subjected to: microwaves, chemical preparation, mechanical as well as blanching appro...

In this paper, one microwave-hot air drier was designed and manufactured and then was evaluated. In the manufactured drier, one circuit was employed for feeding Magnetron lamp with nominal power of 1.3 kW and frequency of 2.45 GHz in order to produce microwaves. Hot air was produced using six 700 W heaters and a 175 rpm fan. The drier container vol...

An adjustable three-point hitch dynamometer with a draft capacity of 50 kN was developed to measure forces on the tractor and mounted implements. The design concept of the dynamometer was based on two linkage frames mounted between tractor links and the implement. The force sensing elements were comprised of a loadcell that was installed between th...

Drying characteristics of Quercus were determined experimentally as a function of temperature, air velocity, and variety (Quercus Persica and Quercus Libani). In order to estimate and select a suitable drying curve, five different thin layer drying models were fitted to the experimental data. Experiments were performed at the air temperatures of 50...

Biodiesel has been a mater of importance in recent years. Environmental challenges have been key factors to justify the necessity of a renewable clean fuel. On the other hand, the production and utilization of biodiesel in a proper state is of concern regarding the numerous plants and industries engaged with the biodiesel. Economical production of...

Tomato is a major fruit, as well as a major food science product. There is a need of determining the quality attributes of this fruit (nondestructively) due to the increasing demand of the in agro-industrially controlled areas. Most of the commonly employed techniques are time consuming and involve a considerable degree of manual work. Sample prepa...

In this paper an intelligent walnut recognition system combining acoustic emissions analysis and Multilayer Feedforward Neural Network (MFNN) classifier was developed and tested for classification of walnuts in three classes. To evaluate the performance of the system, 326 samples were used. Walnuts were divided into empty, average and fully develop...

Tomato (Lycopersicon esculentum L.) is a valuable fruit cultivated in the world as an important plant. There are a lot of industries engaged with the drying, processing, quality control and sorting of tomato. A rapid and reli-able measurement of qualitative factors of tomato and its products can be a serious necessity for the producers and industri...