scholarly journals Effect of moisture content on terminal velocity of lentil grain

2019 ◽  
Vol 65 (No. 1) ◽  
pp. 7-12
Author(s):  
Zahra Basati ◽  
Ezzatollah Askari Asli- Ardeh ◽  
Vali Rasooli-Sharabiani

One of the aerodynamic characteristics of lentil is its terminal velocity. In order to determinate the terminal velocity, was designed a vertical wind tunnel. It was fabricated based on existing methods and standards. For decreasing the non-uniformity of airflow in the vertical wind column, was used a honey comb test area with 5 mesh screens. So, a wind tunnel nozzle was designed and fabricated using Morel method with the aim of increasing airflow rate and decreasing losses due to mesh screens. The height and section area of tunnel were 1.425 m and 0.1 × 0.1 m2, respectively. The pressure loss values were calculated at different parts of tunnel and then, the required power of tunnel was determined. In this study, lentil grains of Kimia and Gachsaran varieties were separated at three groups based on their size (small, medium and large). Then, the terminal velocity was measured at 5 levels of moisture content (8, 12, 16, 20 and 24% (w.b.)) for each group. The results showed that Kimia and Gachsaran variety had the highest (7.204 m·s–1) and the lowest (6.987 m·s–1) terminal velocity, respectively. The mean value of terminal velocity increased linearly from 6.751 to 7.396 m·s–1 by increasing the moisture content from 8 to 24% (w.b.). Also, by increasing the grains dimension from small to large, the terminal velocity increased from 6.345 to 7.792 m·s–1.

2014 ◽  
Vol 28 (3) ◽  
pp. 389-394 ◽  
Author(s):  
Feizollah Shahbazi ◽  
Saman Valizadeh ◽  
Ali Dowlatshah

Abstract The objective of this study was the evaluation of the aerodynamic properties of Makhobeli, triticale and wheat seeds as a function of moisture content from 7 to 27% (w.b). The results showed that the terminal velocity of triticale and wheat seeds increased linearly from 5.37 to 6.42 and from 6.31 to 8.02 m s-1, respectively, as the moisture content increased from 7 to 27%. Over this same moisture content range, the terminal velocity of Makhobeli seeds varied following a polynomial relationship from 4.52 to 5.07 m s-1. Makhobeli seeds had terminal velocities with a mean value of 4.73 m s-1, at different moisture contents, compared to the mean values of 5.89 and 7.13 m s-1 for triticale and wheat seeds, respectively. The mean value of drag coefficient was 1.12 for Makhobeli compared to the values of 0.92 and 0.85 for triticale and wheat, respectively. The analysis of variance showed that there were significant differences between the terminal velocity (at 1 % probability level) and drag coefficient (at 5% probability level) of Mak-hobeli with triticale and wheat seeds, which suggests that aerodynamic separation of Makhobeli from triticale and wheat is possible.


Author(s):  
Mingjian Zhang ◽  
Feng Huang ◽  
Qing Chen ◽  
Le Wang ◽  
Haisheng Wang ◽  
...  

A mathematical model was established to predict the mean value and variance of tobacco strip during drying processing, based that the physical and chemical properties of tobacco strip as agriculture products show probability distributions. The results show that the model can predict the mean value of moisture content at different times, and there is a certain deviation in predicting the variance of moisture content at initial stage of drying process. However, the prediction value of the variance of tobacco strip is much more accurate while the moisture content is between 8% and 10%, which is the interval of quality requirements.Keywords: tobacco strip; drying; mean value;variance model.  


2013 ◽  
Vol 5 (3) ◽  
pp. 545-553 ◽  
Author(s):  
M. G. Sarower ◽  
S. Bilkis ◽  
M. A. Rauf ◽  
M. Khanom ◽  
M. S. Islam

The biochemical composition (proteins, lipid, ash and moisture) of different parts of the body (gill, meat, egg) of fattened and natural mud crab Scylla serrata was determined. Twenty four samples of S. serrata (12 from wild & 12 from fattening farm) of different sizes and sexes (half of the sample is male) were used in this study. The mean protein and lipid contents are significantly (p<0.05) higher in fattened crabs than natural in natural crabs regardless of size and sexes.  Moisture and ash were higher in natural crab than in fattened ones. The highest and lowest moisture content was noticed in gills and eggs in both natural and fattened crabs. Protein and lipid contents were comparatively higher in eggs than in other body parts. Female crabs contained high protein and lipid than males in both natural and fattened crabs.  From the results of this study it may considered that fattened crab might be comparatively superior to natural crabs as they appear to provide higher levels of protein and fat  for human nutrition. Keywords: Biochemical composition; Natural and Fattened mud crab; Scylla serrata   © 2013 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. doi: http://dx.doi.org/10.3329/jsr.v5i3.14082 J. Sci. Res. 5 (3), 545-553 (2013)


1972 ◽  
Vol 25 (2) ◽  
pp. 359 ◽  
Author(s):  
BF Lino

Daily spermatozoan output from the urogenital tract (DSOU), scrotal circumference, testis weight, and the numbers of spermatozoa in the epididymis and other parts of the urogenital tract were measured in 10 rams. Testis weight and the numbers of spermatozoa in the head, body, and tail of the epididymis and in the vas deferens and ampulla were found to be bilaterally symmetrical in each ram. The daily spermatozoan output from the urogenital tract was linearly correlated with testis weight (r = o� 83), with epididymal spermatozoan reserves (r = 0'86), with extragonadal spermatozoan reserves (r = 0�90), and with the total number of spermatozoa in the urogenital tract (r = O� 84). The significance levels of the regression coefficients indicated that these parameters would give good estimates of each other. The total number of spermatozoa in the urogenital tract of all rams at slaughter divided by the predicted time taken for spermatozoa to traverse the tract was found to be approximately 6% below the mean value for the daily spermatozoan output of all rams.


2015 ◽  
Vol 29 (3) ◽  
pp. 391-396 ◽  
Author(s):  
Feizollah Shahbazi ◽  
Saman Valizadeh ◽  
Ali Dowlatshah ◽  
Ezatollah Hassanzadeh

Abstract Aerodynamic properties of solid materials have long been used to convey and separate seeds and grains during post-harvest operations. The objective of this study was evaluation of the aerodynamic properties of green and red lentil seeds as a function of moisture content from 10 to 25% (w.b.). The results showed that as the moisture content increased from 10 to 25%, the terminal velocity of seeds increased, following a linear relationship, from 6.90 to 9.14 and from 6.37 to 7.67 m s−1 for green and red lentil seeds, respectively. Seeds of the green variety had terminal velocities with a mean value of 7.89 m s−1, while the red variety had a mean value of 7.02 m s−1, for moisture content from 10 to 25%. The Reynolds number increased linearly from 2 310.90 to 3 269.23 and from 1 215.02 to 1 535.09 for green and red lentil seeds, respectively, with the increase of seeds moisture content from 10 to 25%. While, drag coefficient decreased from 0.69 to 0.40 and from 0.84 to 0.69 for green and red lentil seeds, respectively, with the increase of moisture content. Mathematical relationships were developed to relate the change in seeds moisture content with the values of aerodynamic properties obtained. The analysis of variance showed that the effect of moisture content on all aerodynamic properties of lentil beans was significant at the 1% probability level.


2015 ◽  
Vol 29 (1) ◽  
pp. 121-126 ◽  
Author(s):  
Feizollah Shahbazi

Abstract Aerodynamic properties of solid materials have long been used to convey and separate seeds and grains during post harvest operations. The objective of this study was the evaluation of the aerodynamic properties of mung bean seeds as a function of moisture content and two grades referred to above and below a cut point of 4.8 mm in length. The results showed that as the moisture content increased from 7.8 to 25% (w.b.), the terminal velocity of seeds increased following a polynomial relationship, from 7.28 to 8.79 and 6.02 to 7.12 m s-1, for grades A and B, respectively. Seeds at grade A had terminal velocities with a mean value of 8.05 m s-1, while at grade B had a mean value of 6.46 m s-1. The Reynolds number of both grades increased linearly with the increase of seeds moisture content, while the drag coefficient decreased with the increase of moisture content. Mathematical relationships were developed to relate the change in seeds moisture content with the obtained values of aerodynamic properties. The analysis of variance showed that moisture content had a significant effect, at 1% probability level, on all the aerodynamics properties of mung beans.


2017 ◽  
Vol 21 (9) ◽  
pp. 1262-1272 ◽  
Author(s):  
Shouying Li ◽  
Yangchen Deng ◽  
Wei Zhong ◽  
Zhengqing Chen

To investigate the aerodynamic characteristics of stay cables attached with helical wires, a series of wind tunnel tests and computational fluid dynamics simulations were both carried out on the smooth and helical-wire cable models. The diameters of helical wires include 2, 3, and 4 mm, and the distances between adjacent helical wires include 200, 300, and 600 mm. Pressure taps were uniformly arranged on seven cross sections of the cable models. First, wind tunnel tests including 50 test cases were conducted to measure the wind forces and wind pressures on the cables using the forced vibration system in HD-2 wind tunnel. The effects of the helical wires on the mean and fluctuating aerodynamic forces and the correlation coefficients along the cable axis were investigated in detail based on the experimental data. Second, large Eddy simulation module incorporated in software FLUENT® was used to simulate the aerodynamic forces on the smooth and helical-wire cables. The parameters of the cable and the helical wire are similar to those used in the wind tunnel tests. The results show that helical wires can attenuate vortex shedding and reduce the wind pressure correlation along the cable axis. Within the Reynolds number range from 0.4 × 105 to 1.6 × 105, the mean drag force of the helical-wire cable is lower than the value of the smooth cable, and the correlation coefficient decreases with the increase in wind velocity. The results obtained from wind tunnel tests and computational fluid dynamics simulations agree well with each other. Furthermore, the wind velocity contour around the helical-wire cables obtained from computational fluid dynamics simulations visually indicates that the approaching flow is forced to separate at the surface of the helical wire in advance, which makes the vortex shedding disorder along the cable axis.


1942 ◽  
Vol 15 (1) ◽  
pp. 216-219
Author(s):  
Leonard H. Cohan ◽  
C. R. Johnson

Abstract The moisture content of carbon black should be kept approximately constant if maximum accuracy in rubber testing is to be attained. In this laboratory we have found it convenient to equilibrate blacks at about 30 per cent humidity, under which condition most rubber channel blacks adsorb 1.5 to 2.0 per cent water. In the case of most of the properties of tread stocks, this precaution decreases the average deviation from the mean value in any series of experiments. In the case of extrusion tests, the effect of adsorbed moisture is so great that the use of a standard moisture content, or at least the determination of moisture content at the same time as the black is milled for extrusion, is necessary if reproducible results are to be expected.


Author(s):  
Offurum Julius Chigozie ◽  
C.M. Morgan

The water content determination of two maize species (Yellow corn- and White corn- ) located at Ohaji in Imo State of Nigeria were  considered in this study. This was motivated by the regular reported cases of the seed post-harvest spoilages, especially in the local communities. And the moisture content of a particular seed could vary according to the various location of crop, presumably due to the soil texture. The moisture content of a given crop seed can influence its storage value, as well as its choice of selection during manufacturing processes. It was, thus, necessary to determine the moisture content of the two maize species (white and yellow corn) from Ohaji in Imo State of Nigeria, in order to identify their dispositions, especially during storage. Modified High Constant Temperature Oven method, as prescribed by the International Seed Testing Association (which involves preliminary pre-drying and grinding), was employed, at a temperature of 102oC. This involved the use of dry-weight technique, which is expressed as a percentage of the dry weight of the seeds. The procedure for each sampling was replicated accordingly, and the mean value identified as the actual result. The moisture content for Sample A (white corn) was found to be 31.7%, while that of Sample B (yellow corn) was found to be 21.5%, which shows that the yellow corn would always have longer storage value than the white corn. As any change in the seed moisture content has a way of affecting its storage life, it is advisable not to store the white corn longer than it could be applied in the yellow corn for a better storage value.Keywords: Determination, Moisture Content, White Corn, Yellow Corn, Dry-weight Basis


2013 ◽  
Vol 44 (2s) ◽  
Author(s):  
Marcello Biocca ◽  
Pietro Gallo ◽  
Paolo Menesatti

Agricultural fertilisers are generally applied by means of centrifugal disk spreaders. The machinery, the working conditions and the physical characteristics of fertilizers (including the aerodynamic characteristics of particles) may affect the behaviour of particles after the discarding from the spreader. We investigated the aerodynamic properties of organo-mineral fertilisers (a class of slow release fertilisers that are less investigated since they are relatively new in the market) using a vertical wind tunnel similar to an elutriator. In the same time, the morphological characteristics of individual fertilizer particles were measured by means of an image analysis procedure. In the study we compare six different fertilisers and we discuss the suitability of the employed methods. The results provide the terminal velocity – Vt – (the velocity value that overcome the gravity force of the particles) of the particles, ranging from 8.60 to 9.55 m s-1, and the relationships between Vt and some physical properties (mass, shape, dimensions) of the fertilizers. Moreover, the results of field distribution trials show the behaviour of the tested fertilizers during practical use. Such data can contribute to enhance the quality of application of these products in field.


Sign in / Sign up

Export Citation Format

Share Document