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Papers by farhad khoshnam
International Journal of Engineering, Oct 1, 2015
The Journal of Engine Research, Jul 10, 2017
International journal of automotive engineering, Sep 15, 2016
The Journal of Engine Research, Apr 15, 2016
Agriculturae Conspectus Scientificus (Poljoprivredna Znanstvena Smotra), Feb 5, 2016
Non-destructive impulse response technique was tested on two melon varieties ('Zard-Eyvanekey' an... more Non-destructive impulse response technique was tested on two melon varieties ('Zard-Eyvanekey' and 'Sousky-Sabz') in fi ve diff erent stages of ripening. Resonance frequency and sound pressure level (SPL) from the impulse response were compared with mass, elastic modulus, soluble solids contents (TSS) and sensory evaluation. Among acoustic and destructive parameters, resonance frequency is an indicator to distinguish of diff erent maturity stage of the melon in both varieties. Th e sound pressure level (SPL) was not a reliable parameter to evaluate melon ripeness. It was established that the impulse response technique is useful to decide fruit maturity stage and appropriate harvest time.
علوم و صنایع غذایی, Apr 1, 2020
Journal of Thermal Analysis and Calorimetry, Jun 29, 2020
In the present work, the first and second laws of thermodynamics were used to perform energy and ... more In the present work, the first and second laws of thermodynamics were used to perform energy and exergy analyses for deep bed drying of paddy in a convective dryer. Also, the equivalent specific CO 2 emission was assessed. Drying experiments were carried out at drying air temperatures of 40, 50 and 60 °C, and air flow rates of 0.008, 0.012 and 0.017 m 3 s −1. Energy utilization, energy utilization ratio and energy efficiency were obtained to be in the range of 0.061-0.1412 kJ s −1 , 22.41-46.81% and 4.37-8.56%, respectively. Exergy loss decreased continually with drying time and the average values ranged from 0.019 to 0.081 kJ s −1. Exergy efficiency varied in the range of 32.44-66.91%. Energy and exergy efficiency was improved at low temperature-low flow rate and high temperature-high flow rate, respectively. The results of environmental analysis declared that specific CO 2 emission ranged from 3.83 to 8.42 kg CO 2 kg −1 water where high temperature-low flow rate drying air reduced the footprint.
Yüzüncü Yıl Üniversitesi Tarım Bilimleri Dergisi, May 31, 2016
Food Science and Technology
Latin American Applied Research - An international journal, 2022
The present work aimed mainly at investigating the influence of tissue structure on dehydration c... more The present work aimed mainly at investigating the influence of tissue structure on dehydration characteristics of zucchini and carrot. Microwave power levels of 100, 350, 550 and 750 W used to dehydrate the samples with thicknesses of 3, 5, 7 and 9 mm. The results showed that moisture removal from the slices occurred in a short accelerating period at the process beginning followed by a falling rate period. The moisture diffusivity increased with both increasing microwave power and the samples thickness where the average values for zucchini and carrot slices changed from 1.17×10-8 to 9.42×10-8 and from 0.73×10-8 to 5.51×10-8 m2 s-1, respectively. The average activation energy for zucchini and carrot slices varied in the range of 1.22–1.68 and 1.57–1.84 W g-1, respectively and decreased with increasing samples thickness.
Introduction Cucumis melo includes a wide range of varieties. The acoustic is production, transmi... more Introduction Cucumis melo includes a wide range of varieties. The acoustic is production, transmission and energy received form medium vibrations. Acoustic or sonic tests applies for grading productions, ripening determination of fruit firmness and sorting of broken eggs and so on in agriculture. Currently these methods are generalized for measuring non-spherical fruits properties. The primary objective of the present research was to investigate the effect of acoustic system variables such as impact places, impactor material type, pendulum angle and sound level meter position on acoustics response of two different melon varieties, including Zard-Eyvanekey and Sousky-Sabz. These results can be useful for designing acoustic implements related to agricultural products. Materials and Methods This research was conducted on 65 samples of Zard-Eyvanekey and Sousky-Sabz varieties (export varieties). A laboratory recording system used to acquire the acoustic impulse information that was comp...
The Journal of Engine Research, 2016
For rolling pneumatic tires, the thermal induced effects are mainly resulted from the visco-elast... more For rolling pneumatic tires, the thermal induced effects are mainly resulted from the visco-elastic behaviour of rubber parts and dissipation of stores strain energy during the cyclic deformations. It is noted that the operating conditions crucially contribute to the rubber hysteresis effect and temperature development in a rolling tire. In the current study, an elaborated 3D FE model is worked up for simulating the certain inflation pressure, loading and velocity conditions for a specified radial tire. Special emphasis is given to transient temperature distribution of interior walls and tire cavities as critical zones. Compared with the experimental tests, the current study gives satisfactory results for the time rate of change in the temperature of tire walls and inside inflated air.
The Journal of Engine Research, 2017
In low ambient temperatures, the engine will have poor output torque and power generation at the ... more In low ambient temperatures, the engine will have poor output torque and power generation at the first cycles of its performance, long start time and huge noxious emissions because of insufficient temperature and quality of airfuel mixture and failure of flame to burn the charge. It is noted that any attempt to increase the charge temperature leads to better combustion conditions. By applying thin ceramic coating over the piston top surface and increasing the temperature of engine inner walls, more efficient combustion in shorter time can be provided for the engine. In current research, a transient thermal study is developed for simulating the engine performance under cold starting conditions and predicting the effect of insulating layer thickness on the charge temperature before ignition timing. The results demonstrate that the ceramic coating can provide higher temperature for piston crown and effectively improve the temperature of charge during the first cranking cycles of engine cold start stage.
Iki kavun ( Cucumis melo L.) cesidinde (Zard-Eyvanekey ve Sousky-Sabz) fiziksel ve mekanik ozelli... more Iki kavun ( Cucumis melo L.) cesidinde (Zard-Eyvanekey ve Sousky-Sabz) fiziksel ve mekanik ozelliklerdeki degisiklikler, olgunlasmanin bes farkli asamasinda calisilmistir. Meyveler, ham, erken olgunlasma, orta olgunlasma, olgun ve asiri olgun asamalarda hasat edilmis ve bazi fiziksel ve mekanik meyve ozellikleri (irilik, ebat, yuzey alani, kuresellik, gercek yogunluk, meyve boy/en orani, tohum boslugu boy/en orani, nem icerigi ve elastikiyet modulu), olgunlasma surecinde incelenmistir. Her iki kavun cesidinde meyve iriligi, ebat, yuzey alani ve kuresellik hasat asamalarinda artarken, meyve boy/en orani, tohum boslugu boy/en orani, nem icerigi ve elastikiyet modulunun azaldigi belirlenmistir. Her iki cesit, genellikle benzer sekilde fakat farkli oranlarda degismistir. Varyans analizi, her ozellik icin cesitlerin farkli asamalari arasinda onemli farkliliklar gostermistir. Iki yonlu ANOVA testi, olgunlasma sirasinda cesitler arasindaki tum ozelliklerin davranisinda onemli etkilesimler ...
Journal of Thermal Analysis and Calorimetry, 2020
International Journal of Engineering, 2015
The purpose of this paper is to evaluate the effect of different methods for improving the temper... more The purpose of this paper is to evaluate the effect of different methods for improving the temperature gradient of a specified gasoline engine piston. With a robust finite element (FE) based software, 3D thermal analyses have been carried out for the piston model. Unlike previous studies, the effects of both fully and locally ceramic layers on the crown top surface were considered. It was found that a fully ceramic layer provides just 10-15% more thermal protection. The effects of thermal dam and lubricating oil temperature on crown and skirt surfaces were then separately investigated. Using these methods, the maximum surface temperature of the piston was greatly improved and the temperature distribution of piston skirt was effectively controlled.
International Journal of Engineering, Oct 1, 2015
The Journal of Engine Research, Jul 10, 2017
International journal of automotive engineering, Sep 15, 2016
The Journal of Engine Research, Apr 15, 2016
Agriculturae Conspectus Scientificus (Poljoprivredna Znanstvena Smotra), Feb 5, 2016
Non-destructive impulse response technique was tested on two melon varieties ('Zard-Eyvanekey' an... more Non-destructive impulse response technique was tested on two melon varieties ('Zard-Eyvanekey' and 'Sousky-Sabz') in fi ve diff erent stages of ripening. Resonance frequency and sound pressure level (SPL) from the impulse response were compared with mass, elastic modulus, soluble solids contents (TSS) and sensory evaluation. Among acoustic and destructive parameters, resonance frequency is an indicator to distinguish of diff erent maturity stage of the melon in both varieties. Th e sound pressure level (SPL) was not a reliable parameter to evaluate melon ripeness. It was established that the impulse response technique is useful to decide fruit maturity stage and appropriate harvest time.
علوم و صنایع غذایی, Apr 1, 2020
Journal of Thermal Analysis and Calorimetry, Jun 29, 2020
In the present work, the first and second laws of thermodynamics were used to perform energy and ... more In the present work, the first and second laws of thermodynamics were used to perform energy and exergy analyses for deep bed drying of paddy in a convective dryer. Also, the equivalent specific CO 2 emission was assessed. Drying experiments were carried out at drying air temperatures of 40, 50 and 60 °C, and air flow rates of 0.008, 0.012 and 0.017 m 3 s −1. Energy utilization, energy utilization ratio and energy efficiency were obtained to be in the range of 0.061-0.1412 kJ s −1 , 22.41-46.81% and 4.37-8.56%, respectively. Exergy loss decreased continually with drying time and the average values ranged from 0.019 to 0.081 kJ s −1. Exergy efficiency varied in the range of 32.44-66.91%. Energy and exergy efficiency was improved at low temperature-low flow rate and high temperature-high flow rate, respectively. The results of environmental analysis declared that specific CO 2 emission ranged from 3.83 to 8.42 kg CO 2 kg −1 water where high temperature-low flow rate drying air reduced the footprint.
Yüzüncü Yıl Üniversitesi Tarım Bilimleri Dergisi, May 31, 2016
Food Science and Technology
Latin American Applied Research - An international journal, 2022
The present work aimed mainly at investigating the influence of tissue structure on dehydration c... more The present work aimed mainly at investigating the influence of tissue structure on dehydration characteristics of zucchini and carrot. Microwave power levels of 100, 350, 550 and 750 W used to dehydrate the samples with thicknesses of 3, 5, 7 and 9 mm. The results showed that moisture removal from the slices occurred in a short accelerating period at the process beginning followed by a falling rate period. The moisture diffusivity increased with both increasing microwave power and the samples thickness where the average values for zucchini and carrot slices changed from 1.17×10-8 to 9.42×10-8 and from 0.73×10-8 to 5.51×10-8 m2 s-1, respectively. The average activation energy for zucchini and carrot slices varied in the range of 1.22–1.68 and 1.57–1.84 W g-1, respectively and decreased with increasing samples thickness.
Introduction Cucumis melo includes a wide range of varieties. The acoustic is production, transmi... more Introduction Cucumis melo includes a wide range of varieties. The acoustic is production, transmission and energy received form medium vibrations. Acoustic or sonic tests applies for grading productions, ripening determination of fruit firmness and sorting of broken eggs and so on in agriculture. Currently these methods are generalized for measuring non-spherical fruits properties. The primary objective of the present research was to investigate the effect of acoustic system variables such as impact places, impactor material type, pendulum angle and sound level meter position on acoustics response of two different melon varieties, including Zard-Eyvanekey and Sousky-Sabz. These results can be useful for designing acoustic implements related to agricultural products. Materials and Methods This research was conducted on 65 samples of Zard-Eyvanekey and Sousky-Sabz varieties (export varieties). A laboratory recording system used to acquire the acoustic impulse information that was comp...
The Journal of Engine Research, 2016
For rolling pneumatic tires, the thermal induced effects are mainly resulted from the visco-elast... more For rolling pneumatic tires, the thermal induced effects are mainly resulted from the visco-elastic behaviour of rubber parts and dissipation of stores strain energy during the cyclic deformations. It is noted that the operating conditions crucially contribute to the rubber hysteresis effect and temperature development in a rolling tire. In the current study, an elaborated 3D FE model is worked up for simulating the certain inflation pressure, loading and velocity conditions for a specified radial tire. Special emphasis is given to transient temperature distribution of interior walls and tire cavities as critical zones. Compared with the experimental tests, the current study gives satisfactory results for the time rate of change in the temperature of tire walls and inside inflated air.
The Journal of Engine Research, 2017
In low ambient temperatures, the engine will have poor output torque and power generation at the ... more In low ambient temperatures, the engine will have poor output torque and power generation at the first cycles of its performance, long start time and huge noxious emissions because of insufficient temperature and quality of airfuel mixture and failure of flame to burn the charge. It is noted that any attempt to increase the charge temperature leads to better combustion conditions. By applying thin ceramic coating over the piston top surface and increasing the temperature of engine inner walls, more efficient combustion in shorter time can be provided for the engine. In current research, a transient thermal study is developed for simulating the engine performance under cold starting conditions and predicting the effect of insulating layer thickness on the charge temperature before ignition timing. The results demonstrate that the ceramic coating can provide higher temperature for piston crown and effectively improve the temperature of charge during the first cranking cycles of engine cold start stage.
Iki kavun ( Cucumis melo L.) cesidinde (Zard-Eyvanekey ve Sousky-Sabz) fiziksel ve mekanik ozelli... more Iki kavun ( Cucumis melo L.) cesidinde (Zard-Eyvanekey ve Sousky-Sabz) fiziksel ve mekanik ozelliklerdeki degisiklikler, olgunlasmanin bes farkli asamasinda calisilmistir. Meyveler, ham, erken olgunlasma, orta olgunlasma, olgun ve asiri olgun asamalarda hasat edilmis ve bazi fiziksel ve mekanik meyve ozellikleri (irilik, ebat, yuzey alani, kuresellik, gercek yogunluk, meyve boy/en orani, tohum boslugu boy/en orani, nem icerigi ve elastikiyet modulu), olgunlasma surecinde incelenmistir. Her iki kavun cesidinde meyve iriligi, ebat, yuzey alani ve kuresellik hasat asamalarinda artarken, meyve boy/en orani, tohum boslugu boy/en orani, nem icerigi ve elastikiyet modulunun azaldigi belirlenmistir. Her iki cesit, genellikle benzer sekilde fakat farkli oranlarda degismistir. Varyans analizi, her ozellik icin cesitlerin farkli asamalari arasinda onemli farkliliklar gostermistir. Iki yonlu ANOVA testi, olgunlasma sirasinda cesitler arasindaki tum ozelliklerin davranisinda onemli etkilesimler ...
Journal of Thermal Analysis and Calorimetry, 2020
International Journal of Engineering, 2015
The purpose of this paper is to evaluate the effect of different methods for improving the temper... more The purpose of this paper is to evaluate the effect of different methods for improving the temperature gradient of a specified gasoline engine piston. With a robust finite element (FE) based software, 3D thermal analyses have been carried out for the piston model. Unlike previous studies, the effects of both fully and locally ceramic layers on the crown top surface were considered. It was found that a fully ceramic layer provides just 10-15% more thermal protection. The effects of thermal dam and lubricating oil temperature on crown and skirt surfaces were then separately investigated. Using these methods, the maximum surface temperature of the piston was greatly improved and the temperature distribution of piston skirt was effectively controlled.