Today, the use of aerodynamic dryers for drying various types of fruit crops is very current. In them, the electric energy spent on the drive of the centrifugal fan is transformed into thermal energy due to the mutual friction of the air flows circulating in the closed chamber. In order to increase the energy efficiency of the drying process, the heat of the waste drying agent was used in the research. The presented dryer was equipped with a combined heat exchanger. In order to predict the thermal performance of the combined heat exchanger depending on external factor variables, the dependence of the temperature of the fresh drying agent at the outlet of the combined heat exchanger on the dryer operation time is theoretically determined on the basis of the heat balance equation. The air solar collector in the combined heat exchanger made it possible to increase the temperature of the drying agent at the outlet by another 10oC without extra costs of electrical energy. A comparative analysis of the results of experimental and theoretical studies showed their high convergence.
A grain drying complex based on solar energy, including a grain storage with a built-in solar drying system and a drum solar dryer for grain, is proposed. The construction and principle of operation of the grain drying complex is described. The basis of each of the solar drying systems of the complex is the presence of two solar collectors, one of which provides heating of the drying agent at the inlet into the drying chamber, and the second-heating of the used drying agent in the exhaust pipe to increase its flow rate and, accordingly, the intensification of grain drying. Availability of gravel or water heat accumulators allows to carry out the process of grain drying or grain storage, at night and under adverse weather conditions without the risk of self-heating. The optimum capacity of the gravel accumulator is 0.5-0.75 m 3 per 1 m 2 of solar collector area. Drum solar dryer provides guaranteed drying of a grain batch for 6-7 hours of the day time and a grain batch for the night time. It was found that the optimum thickness of the grain layer in the drying process is 50-70 cm and specific load is up to 100 kg of grain per square meter of the horizontal solar collector area.
The diversity of natural conditions and cultivated crops, the different level of fields cultivation determines the difference in optimal design parameters and functional properties of sprayers for their effective use. Field experiment methods, calculation method and computer simulation method are used to substantiate the optimal parameters of sprayers in relation to various conditions. In computer modeling, not only the structural, but also the dynamic characteristics of the units are necessarily taken into account. One of the stages in computer modeling of the spraying units functioning is the preliminary formalization of non-stationarity and non-linearity of their static and dynamic properties. The formula for the dependence of the main moment of inertia of the sprayer at a different level of liquid in a cylindrical container was obtained by formalizing the results of a full-scale experiment. The original stand and the method of carrying out are proposed for conducting a full-scale experiment. The mathematical dependence of the change in the height of the center of mass of the spraying unit on the design parameters of the tank and the liquid level in it was obtained by the calculation method. The results obtained can be used in Simulink modeling of the functioning of the spraying unit and determining its optimal parameters for various operating conditions using a known method.
It was found that the shafts of soil in the near-growth zone and uneven topography of row spacings reduce the quality of the mechanized method of cutting remontant raspberries. Statistical indicators of the microprofile of row spacing in the range: dispersion 2.0 - 4.0 cm2, standard deviation 1.4 -2.0 cm, cutoff frequency 8 - 15 were obtained by the method of unleveling and statistical processing. The design schemes of mounted machines for removing shafts of soil from the protection zones near the mouth with leveling the profile on the same level with the soil profile in the raspberry row have been developed. The basis of the structures is an arched frame hinged on the tractor from the side and controlled by a hydraulic cylinder. Two additional frames are pivotally attached to the lower ends of the frame. Rotary working bodies are provided for easy soils. Plow tools with a cut-out blade and vane rotors are designed for heavy soils. The developed machines allow removing soil banks from the raspberry protective zones on both sides of the row in one pass. The developed machines allow removing soil banks from the raspberry protective zones on both sides of the row in one pass. The soil from the shafts is scattered into the row-spacing, leveling its irregularities, and the bottom of the furrow is formed on the same level with the soil profile in the raspberry row. This creates an optimal terrain for the subsequent movement of the mower.
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