Bioenergy
A. Waismoradi; M. E. Khorasani; H. Bahrami; S. M. Safieddin Ardebili; H. Zaki Dizaji
Abstract
IntroductionToday, the number of diesel engines is increasing due to their high efficiency and low greenhouse gases. In the present study, the effect of adding nano cellulose as nanoparticles to diesel fuel on the performance parameters and emissions of diesel engine was investigated. Nano cellulose ...
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IntroductionToday, the number of diesel engines is increasing due to their high efficiency and low greenhouse gases. In the present study, the effect of adding nano cellulose as nanoparticles to diesel fuel on the performance parameters and emissions of diesel engine was investigated. Nano cellulose was provided by the Nano Novin Company in Sari. Nano cellulose values were considered at 3 levels of zero, 25 ppm and 75 ppm. Also, the tests were performed at 3 engine speed of 1600, 2000 and 2400 rpm in full load mode.Materials and MethodsIn this study, nanocellulose was used as nanoparticles to add to diesel and to evaluate the performance and emission parameters of the engine. To prevent the deposition of nano cellulose in diesel fuel, jelly type nano cellulose was used. The samples were named after adding different amounts of nano cellulose, abbreviated D100N0, D100N25 and D100N75. D100 means 100% pure diesel and N means different amounts of nano cellulose with different amounts. Ultrasound was used to obtain homogeneous samples. About 3 liters were prepared from each sample so that it could be used for at least 3 repetitions. The required tests were performed at three different speeds of 1600, 2000 and 2400 rpm in full load mode. The necessary equipment was used to measure the performance parameters and air emissions, including diesel engine connected to the dynamometer, emissions measuring device, fuel system and control room (to apply the load and provide conditions for each treatment and data collection). The air-cooled, four-stroke, compression-ignition single-cylinder engine made by the Italian company Lombardini was used. The D400 eddy current dynamometer made in Germany was used. The ability to measure power by this dynamometer is a maximum of 21 hp, a maximum speed of 10,000 rpm and a maximum torque of 80 N.m. To measure of emissions, the MAHA MGT5 emissions meter was used. This device is able to measure the values of CO, CO2, NOX, O2 and UHC.Results and DiscussionThe results showed that increasing engine speed in all fuel combinations increased engine power, specific fuel consumption, carbon monoxide and unburned hydrocarbons and decreased torque. Also, increasing the amount of nano cellulose per engine speed increased the amount of power and torque, but reduced the specific fuel consumption, carbon monoxide and unburned hydrocarbons. The amount of NOX increased with increasing engine speed, but at each engine speed the addition of 25 ppm nanocellulose to pure diesel significantly increased the amount of NOX. But at low speed, increasing 75 ppm nanocellulose to pure diesel reduced the amount of NOX.ConclusionThe results of this study showed that the addition of nano cellulose as nanoparticles can improve the performance of diesel engines and also reduce the amount of emissions gases emitted from the engine. The results also showed that increasing 25ppm nanocellulose had a greater effect on engine performance. But to reduce the amount of emissions, 75 ppm nanocellulose was better.
Design and Construction
A. Rezaei; H. Masoudi; H. Zaki Dizaji; M. E. Khorasani
Abstract
Introduction The cereal combine harvester is one of the agricultural machines that works in difficult conditions and its parts are constantly under various static and dynamic loads. For the optimal design of vehicle parts, types and values of loads applied to them must be determined correctly. The purpose ...
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Introduction The cereal combine harvester is one of the agricultural machines that works in difficult conditions and its parts are constantly under various static and dynamic loads. For the optimal design of vehicle parts, types and values of loads applied to them must be determined correctly. The purpose of this study was to design and fabricate an electronic system that could instantly measure and store the amount of vertical load exerted on the rear axle of grain combine harvester in various conditions to be used in the design and optimization of the axle.Materials and Methods Main components of the designed system included a steel coupling, a disc loadcell (H2F-C2-10t ZEMIC model), an electronic board for amplifying loadcell output voltage, a data logger (AdvanTech DAQ Navi model), a 12-volt battery, and a laptop. A special steel coupling was designed in CATIA software for connecting the loadcell to the axle. The loadcell was placed between the coupling plates and then the coupling was installed on the center point of the rear axle of a JD 955 combine harvester. A standard tensile-compression testing machine (Cantam STM-150) was used to calibrate the loadcell. The relationship between the input load and the loadcell output voltage was linear and had a high coefficient of determination (R2 = 0.9991). In the static test, the vertical load exerted on the axle was recorded by the electronic system while the combine was stopped and the combine engine was in ON/OFF modes. In the dynamic test, the combine was driven in three positions including asphalt road, dirt road, and wheat field at three different forward speeds, and loads on the rear axle were recorded by the electronic system. Finally, the data obtained from the tests were analyzed as a factorial experiment in a completely randomized design with five replications in Excel and SPSS software.Results and Discussion The average static loads on the combine rear axle in ON and OFF modes were 14.908 and 14.905 kN, respectively. The results of the Student's t-test of paired samples to compare the values of axle vertical loads in two modes of static load measurement showed that there is no significant difference between the axle loads in ON and OFF mode of the engine at 1% probability level. The average vertical loads on the rear axle of the combine were equal to 15.20, 15.27, and 15.28 kN, while driving on asphalt roads at speeds of 10, 15, and 20 km h-1 respectively. These values were equal to 17.57, 17.99, and 18.15 kN, while driving on the dirt road at speeds of 2, 4, and 6 km h-1 respectively, and they were equal to 16.47, 18.01, and 17.78 kN when harvesting wheat in the field at speeds of 3, 4, and 5 km h-1 respectively. The average load applied on the axle in the turning path was more than the load applied in the straight path, which indicates load transfer to the rear axle during turning. The effect of forward speed and path type on the amount of axle load was significant at a 1% probability level, but their interaction was not significant. Therefore, the critical conditions for applying load on the rear axle of combine harvester are occurred while combine turns with high forward speed, and the design of the axle should be based on these conditions. The maximum load on the axle was obtained equal to 50 kN on the dirt road, which was due to the combine movement on a steep uphill at the end of the path.Conclusion Evaluation of the system in different conditions showed that the performance and accuracy of the system are acceptable and the data of this system can be trusted and used to measure the vertical load on the rear axle of the combine. The current rear axle of the JD955 combine harvester looks relatively safe, but at some very rugged elevations, especially steep uphills, it suffers from a lot of stress that may cause damage. So, optimizing the axle such as increasing the thickness of the triangular piece in the middle of axis and using a stronger alloy for the middle areas of the axle are recommended.
K. Andekaeizadeh; M. J. Sheikhdavoodi; M. E. Khorasani
Abstract
Introduction Main part of energy consumption in agricultural mechanization is tillage operations therefore optimization of energy consumption in tillage operation is very important. A management method for system to optimize in agriculture is Simple Additive Weighting (SAW) methodology that this method ...
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Introduction Main part of energy consumption in agricultural mechanization is tillage operations therefore optimization of energy consumption in tillage operation is very important. A management method for system to optimize in agriculture is Simple Additive Weighting (SAW) methodology that this method can operate according to criteria of the systems. This method states that, which system has better performance? (for example the system for agricultural tractors, type of implements, methods of tillage, planting and harvesting, and etc). Fuel consumption is the most important factor in terms of energy consumption in tractor because the fuel energy contributes to help tractor to work . Specific draught is important force that measured for investigation of energy consumption of tillage implements, it can show the amount of drawbar force that optimized (for work width 1 meter implements tillage) by using this method. The multiplication of the drawbar force in forward speed factor resulted drawbar power. The most common method is using of tractors drawbar power in mechanized agriculture. Important factor for assessment and determination performance of tractor is drawbar power. Several studies have been showed that about 20 to 55%of available drawbar power was wasting by implements tillage. Another important parameters that affect on traction efficiency pull’s machine is slip. A simple additive weighting two-step procedure involving basic weighted as follows: (1) scale the values of all attributes to make them comparable; (2) sum up the values of the all attributes for each alternative. Materials and Methods In this study, three implements tillage were studied including moldboard plow, disk plow and disk harrow and they called A, B and C, respectively. Three different forward speeds of 3, 4, 5, 6 km.h-1 for each implements were selected according to the type of work at various depths. In this study fuel consumption factor was measured by means of micro-oval flow meter, forward speed was measured by a Doppler radar, Slip was measured by Proxy Sensor, and drawbar force was measured by a three point auto hitch dynamometer. Depth tillage was maintained by depth-knob control system. tillage implements for comparison proper class was rated tables (1), (2) and (3) that includes low depth (12.4 cm moldboard plow, disk plow 12.3 cm and 12.4 cm disk harrow), middle depth (18 cm moldboard plow, disk plow 17.4 cm and 15.2 cm disk harrow) and the high depth (23.5 cm moldboard plow, disk plow 23.4 cm and 17.2 cm disk harrow). Results and Discussion The results of Table 5 shows a higher combined ratio of the amount of energy that is optimum performance in the form of (1), (2) and (3). Also Combined ratio is a way that the whole system will be valued according to their criteria that objective criteria according to the study, we classified as positive and negative criteria and all its problems the system had a higher combined ratio than the rest of the system is the optimal system performance. Kheiralla et al. (2004) in their research used statistical methods and indicated that energy efficiency disk harrow, disk plow and moldboard plow was better than the other devices but Simple Additive Weight way of energy efficiency in different conditions partially expressed. Conclusion The results showed that disk plow in different depth tillage and forward speed, has higher energy efficiency. Disk harrow compared with other tillage implements recommended for the high depth. Disc harrow is not optimal in the low depth because it compared to other implements has lower slip and tractive efficiency. Moldboard plow is optimum use energy in depth and average speeds (4 and 5 km h-1).
N. Hafezi; M. J. Sheikhdavoodi; S. M. Sajadiye; M. E. Khorasani
Abstract
Introduction
Potato (Solanumtuberosum L.) is one of the unique and most potential crops having high productivity, supplementing major food requirement in the world. Drying is generally carried out for two main reasons, one to reduce the water activity which eventually increases the shelf life of food ...
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Introduction
Potato (Solanumtuberosum L.) is one of the unique and most potential crops having high productivity, supplementing major food requirement in the world. Drying is generally carried out for two main reasons, one to reduce the water activity which eventually increases the shelf life of food and second to reduce the weight and bulk of food for cheaper transport and storage. The quality evaluation of the dried product was carried out on the basis of response variables such as rehydration ratio, shrinkage percentage, color and the overall acceptability. Drying is the most energy intensive process in food industry. Therefore, new drying techniques and dryers must be designed and studied to minimize the energy cost in drying process. Considering the fact that the highest energy consumption in agriculture is associated with drying operations, different drying methods can be evaluated to determine and compare the energy requirements for drying a particular product. Thermal drying operations are found in almost all industrial sectors and are known, according to various estimates, to consume 10-25% of the national industrial energy in the developed world. Infrared radiation drying has the unique characteristics of energy transfer mechanism. Kantrong et al. (2012) were studied the drying characteristics and quality of shiitake mushroom undergoing microwave-vacuum combined with infrared drying. Motevali et al. (2011) were evaluated energy consumption for drying of mushroom slices using various drying methods including hot air, microwave, vacuum, infrared, microwave-vacuum and hot air-infrared. The objectives of this research were to experimental study of drying kinetics considering quality characteristics including the rehydration and color distribution of potato slices in a vacuum- infrared dryer and also assessment of specific energy consumption and thermal utilization efficiency of potato slices during drying process.
Materials and Methods
A laboratory scale vacuum-infrared dryer, developed at the Agricultural Machinery and Mechanization Engineering Laboratory of Shahid Chamran University of Ahvaz has been used. The dryer consists of a stainless steel drying chamber; a laboratory type piston vacuum pump, which was used to maintain vacuum in the drying chamber; an infrared lamp with power of 250 W which was used to supply thermal radiation to a drying product; and a control system for the infrared radiator.
Sample Preparation
Fresh potatoes were purchased from a local market in Hamadan province. Potatoes were peeled, washed, and cut into sliced with thickness of 1, 2 and 3 mm by a manual slicer. Drying experiments of potato slices were performed in a vacuum chamber with absolute pressure levels of 20, 80, 140 and 760 mmHg; and radiation intensity of infrared lamp was 0.2, 0.3 and 0.4 W cm-2. The mass change of the sample during drying was detected continuously using an electronic weight scale (Lutron, GM- 1500P, Taiwan) with the accuracy of ±0.05 g.
Evaluation of rehydration capacity of dried potato slices
The rehydration tests measured the gain in weight of dehydrated samples (~5 g), dehydrated samples were rehydrated in 200 cc of distilled water at 100°C for 3 minutes.
Evaluation of color
The color of potatoes was measured on five slices selected randomly, and was described by three coordinates in the RGB color space using computer vision.
Evaluation of specific energy consumption
Energy consumption of dying process came from the electrical energy consumed by the operation of the vacuum pump and the infrared lamp. Specific energy consumption was defined as the energy required for removing a unit mass of water in drying the potato slice.
Evaluation of thermal utilization efficiency
Thermal utilization efficiency is defined as the latent heat of vaporization of moisture of sample to the amount of energy required to evaporate moisture from free water. The latent heat of vaporization of water at the evaporating temperature of 100°C was taken as 2257 kJkg-1.
Results and Discussion
The results of the evaluation of rehydration capacity of potato slices during drying process are shown in Table 1. Statistical analysis (ANOVA, post-hoc Duncan) showed that thickness at probability level of 1% had statistically significant influence on rehydration capacity values of dried potato slices. Moisture of dried slice of potato compared to its fresh was obtained nearly 80% in boiling water (at temperature 100°C) for 3 min. The most color changes of slice after drying was related to green color. According to Table 2 and statistical analysis results showed that factor of thickness was not statistically significant on specific energy. The effect of absolute pressure (p<0.05) and radiation intensity (p<0.01) parameters also interaction of absolute pressure and radiation intensity (p<0.05) had statistically significant influence on specific energy of dried potato slices. According to Table 3 and statistical analysis the factor of absolute pressure had statistically significant at probability level of 5% on thermal utilization efficiency. Also the effect of interaction of absolute pressure and radiation intensity had statistically significant at probability level of 5% on thermal utilization efficiency of dried potato slices. The drying efficiency of potato slices varied between 2.13% to 31.01%.
Conclusions
Dried potato slices at a thickness of 1 mm put in boiling water for three minutes; showed the most amount of water absorption ratio that it was able to absorb the value of 86% more than the initial moisture. The lowest rate of color change before and after the drying process is related to the thickness of the thinnest sliced potatoes. Comparison of energy consumption showed that the radiation intensity of 0.4 W cm-2, absolute pressure level of 80 mmHg and slice thickness of 1 mm had shorter drying time in experimental conditions.
