Zdzisław Kaliniewicz

Numerical modelling of agricultural products on the example of bean and yellow lupine seeds

Abstract Numerical models of bean seeds cv. Złota Saxa and yellow lupine seeds cv. Juno were generated with the use of a 3D scanner, the geometric parameters of seeds were determined based on the models developed, and compared with the results of digital image analysis and micrometer measurements. Measurements of seed length, width and thickness performed with the use of a micrometer, 3D scanner and digital image analysis produced similar results that did not differ significantly at α = 0.05. The micrometer delivered the simplest and fastest measurements. The mean surface area of bean seeds cv. Złota Saxa and yellow lupine seeds cv. Juno, calculated with the use of mathematical formulas based on the results of micrometer measurements and digital image analysis, differed significantly from the mean surface area determined with a 3D scanner. No significant differences in seed volume were observed when this parameter was measured with a 3D scanner and determined with the use of mathematical formulas based on the results of digital image analysis and micrometer measurements. The only differences were noted when the volume of yellow lupine seeds cv. Juno was measured in a 25 ml liquid pycnometer.

The Effect of Seeding Rate on Selected Physical Parameters and the Biomass Yield of Maize

Plant morphology is affected by plant density and uniformity of plant distribution per unit area. This study investigates the effect of seeding rate of two hybrid cultivars of maize (Zea mays L.) harvested for silage on selected physical parameters (stem length, stem diameter, total plant weight and weight of ears with husks), fresh weight yield and ear yield of maize plants. A field experiment was carried out in 2011-2013 on soil of weak rye complex (‘Kosmo’) and a good rye complex (‘Kixxo’). Results were processed by one-way ANOVA, correlation analysis and regression analysis. At constant 0.75 m inter-row spacing, seeding rate (6.5 to 11.9 seeds m-2 for ‘Kosmo’ and 8 to 12 seeds m-2 for ‘Kixxo’) significantly (α = 0.05) influenced evaluated parameters. Higher plant density lowered the weight of plants and ears, and resulted in lower stem diameter. An increase in seeding rate led to a decrease in stem diameter measured at 50, 100 and 150 cm above ground (by ca. 11% to 23% in ‘Kosmo’, and by ca. 3% to 13% in ‘Kixxo’), and an increase in stem length (by 10% to 13% in ‘Kosmo’, and by ca. 8% in ‘Kixxo’). Plants grown with lower seeding rates were larger and heavier. The developed equations are characterized by a good and very good fit to empirical data (multiple correlation coefficient ranged from 0.62 to 0.94 in ‘Kosmo’, and from 0.76 to 0.95 in ‘Kixxo’). This knowledge of the morphological traits of maize is useful to optimize operating parameters of harvesting machines.

Analysis of tank safety with propane-butane on LPG distribution station

Abstract An analysis of the risk of failure in the safety valve – tank with propane-butane (LPG) system has been conducted. An uncontrolled outflow of liquid LPG, caused by a failure of the above mentioned system has been considered as a threat. The main research goal of the study is the hazardous analysis of propane-butane gas outflow for the safety valve – LPG tank system. The additional goal is the development of an useful method to fast identify the hazard of a mismatched safety valve. The results of the research analysis have confirmed that safety valves are basic protection of the installation (tank) against failures that can lead to loss of life, material damage and further undesired costs of their unreliability. That is why a new, professional computer program has been created that allows for the selection of safety valves or for the verification of a safety valve selection in installations where any technical or technological changes have been made.

A relationship between friction plate roughness and the external friction angle of wheat kernels

ABSTRACT The frictional properties of seeds have been extensively studied, but most researchers have identified only the type of tested friction materials (e.g. concrete, steel, wood) without describing their manufacturing characteristics. The aim of this study was to determine the correlations between the external friction angle of wheat kernels vs. the roughness of the friction plate and the basic physical properties of kernels. The experiment was performed on the kernels of winter wheat var. Jensen obtained directly from spikes and threshed kernels. The external friction angle of every kernel was measured on six friction plates characterized by different surface geometry. Measurements were performed in five replications with a photosensor device which registered the external friction angle of kernels. The basic dimensions and the mass of every kernel were measured, and the results were used to calculate four shape factors for the analyzed kernels. The correlations between the evaluated attributes were determined by one-way analysis of variance (ANOVA) and linear correlation analysis. The roughness of the friction plate significantly influenced the external friction angle of wheat kernels. The average values of the angle of external friction ranged from around 16° to around 24°. The lowest value of the angle of external friction was noted for surface roughness of Ra = 0.93 μm, and the highest value – for surface roughness of Ra = 5.86 μm. Higher values of the angle of external friction were observed in kernels obtained directly from spikes than in threshed kernels.