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This paper presents the design of an extended Kalman filter (EKF) as a state-of-charge (SoC) estimator for a lithium–titanate (LTO) battery cell. The design is based on a Thevenin model of the equivalent battery electrical circuit with two parallel resistive-capacitive (RC) elements for the emulation of electrolyte polarization effects. The effectiveness of the proposed SoC estimator is verified through computer simulations on the comprehensive nonlinear battery simulation model featuring battery parameter vs. SoC variations, which is subject to highly dynamic loading regimes.

The concept and a new method for the shielded development of bottom gas hydrates have been proposed, the technological phases and constructive elements of their implementation have been substantiated. The research provides for the realization of the idea suggesting the simultaneous dissociation of the vast areas of a gas hydrate deposit, management of the targeted process of the penetration of methane recovered from gas hydrates into water space and its accumulation under the extensive gas-collecting shield wherefrom it is removed by bottom pipe transportation facilities. To do hydraulic fracturing, a well is drilled into the plane of the junction of the surface of a gas hydrate deposit and the rocks of a roof, the open system of fissures in the rocks of a roof is made through which produced gas is released to a gas-collecting blanket in a water.

A schematic diagram of a transport hybrid power plant using a new design RPE-4.4/1.75 rotary piston air engine is proposed. Its external speed characteristic is determined, according to which the maximum engine power is 8.75 kW at 850 rpm and the maximum torque is 127.54 N∙m at 400 rpm. For various gears and speeds, all the components of the power balance were determined and the dynamic characteristic of the hybrid car was obtained when operated on an air engine. According to the dependences of the power balance, the total traction force from the rotary piston air engine on the driving wheels is 5 kN. The performance of acceleration of a hybrid car while working on an air engine is estimated, namely, the dependences of acceleration, time,and acceleration path are obtained. In urban traffic, the required time to accelerate the car to a speed of 60 km/h is 15.2 s and the path is 173 m. The possible drive range of the hybrid car on compressed air without additional recharging is analyzed. On one cylinder with compressed air with a volume of 100 liters, an initial pressure of 35 MPa, and a final pressure of 2 MPa, the hybrid car can travel about 26 km.

The calculation of parameters of electromechanical converter of a multimodule structure with a common hollow massive rotor was submitted. The structure of high-performance electromechanical converter was shown, which includes not only the elements that perform the basic functions of energy conversion of one type into another and provide biomass being processed by fractional, formative and humidity parameters, but also implements a number of related physical and chemical effects to give new properties of biomass and increase the commercial value of the product. Since the material being processed is simultaneously a load-cooling material, the heat transfer and mechanical loading of the brake and motor module are interrelated. Results of industrial tests of the converter are presented. Comparison of experimental and calculated parameters and characteristics as a whole show good convergence of the results.

An advanced scavenge air cooling system for reciprocating gas engines of integrated energy system for combined electricity, heat and refrigeration generation has been developed. New method of deep scavenge air cooling and stabilizing its temperature at increased ambient air temperatures and three-circuit scavenge air cooling system with absorption lithium-bromide chiller and wet-type cooling tower was proposed. Such cooling method does not require essential constructive changes in the existing scavenge air cooling system but only an addition heat exchanger for chilling scavenge air cooling water of scavenge air low-temperature intercooler closed contour by absorption chiller. A chilled water from absorption chiller is used as a coolant. To evaluate the effect of gas engine scavenge air deeper cooling compared with its typical radiator cooling, data on the dependence of fuel consumption and power output of gas engine on ambient air temperature at the inlet of the radiator are analized. The efficiency of engine scavenge air deep cooling at increased ambient air temperatures was estimated by reducing the gas fuel consumption compared with radiator cooling.

The mathematical model of heat flow and transfer in roof rocks of underground gas gasifier during coal gasification is developed and tested. In terms of geological conditions in the Olkhovo-Nizhnee site (industrial region in Donbass), in Mathcad environment, convective and conductive components of heat flow from reaction channel to upper-lying aquifer are determined. The change in the heat flow from the reaction channel and in the ground water temperature is estimated depending on impermeable layer thickness and water well yield. It is found that after underground coal gasification, water-bearing sandstones accumulate more than 60% of heat migrating from gasifier to enclosing rock mass. It is shown that withdrawal and use of water heated during underground coal gasification will enhance efficiency of the process by 18–25% subject to thickness of partition layer.

Abstract The publication presents the impact of using automatic control systems for operating gas engines aimed at a chilled water production. The purpose of the work is to analyse the possibilities of using automation systems to regulate gas flow. An important parameter of fuel supplied to gas engines used in the production of cold is its amount, which depends on the pressure. Unstable operation of gas distribution systems caused by an extensive network, many customers and operation of devices working with different loads causes improper, unpredictable operation of other devices working in the network. Uncertainty of fuel parameters results in unstable operation of gas engines, their load, and variable production of electricity, heat and cold. Ensuring proper and stable production is a key element of production processes. The concept of building a gas pressure regulation system based on its amount in the network will ensure the required, stable operation of gas engines and refrigeration units coupled with them, and thus provide a guarantee of production of generated media. The presented solution provides a solution to existing problems. The system is based on two dampers coupled to each other and controlled by an automation system controlled by a superior SCADA system.

Abstract The energy efficiency is one of the most important issues nowadays; the problem with the buildings heating is especially relevant for Ukraine. The aim of the paper is to develop a convenient tool building energy performance analysis based on regression model for internal air temperature prediction, depending on a number of internal and external influential factors. The external climatic factors, such as outside air temperature, wind speed and direction, solar heat gains depending on building fenestration surfaces orientation, are considered. Internal factors include heating load, number of floors, air exchange rate etc. In order to achieve the goal, a room dynamic simulation model is created in the EnergyPlus software. A number of simulations are carried out based on the created building energy model . The individual and aggregate selected factors influence on inside air temperature change is considered. The general structure of the multivariate nonlinear regression model for inside air temperature determination is analyzed and selected. Constant coefficients are obtained for each selected influencing factor, and verification of the received nonlinear regression model is performed based on simulation data using January climatic data from the IWEC file. The adequacy of the obtained regression model is estimated by the corrected determination coefficient (R 2 = 0.981) and Fisher's criterion (F = 1324.3), which indicates the high accuracy of the obtained multivariate nonlinear regression. The proposed approach for regression model creation can be used for other architectural and thermal properties of building envelope.

Balastless thin-layer MnO2/Al electrodes without an electroconducting carbon additive in combination with multiwalled carbon nanotubes (MWCNT) MnO2/Al-MWCNT, as well as bulk-modified paste electrodes MnO2 (MWCNT) F4/18H12X9T stainless steel electrodes, have been studied in the redox reaction with lithium in a model accumulator on the basis of propylene carbonate (PC), dimetoxiethane (DME), and 1MLiClO4 and ethyl carbonate (EC), dimethylcarbonate (DMC), and 1M LiClO4 electrolytes. The window of the electrochemical stability of the anode oxidation on MnO2-Al/electrodes in the work range of the potentials for the electrolytes under study is 2.0–4.1 and 2.0–4.2 V, respectively. Because of the high contact resistance between the particles of the thin-layer β/γ-MnO2/Al electrode, its discharge capacity cannot exceed 110–120 mA h/g; however, it is stable through 180 cycles. The discharge capacity volume paste MnO2, F4/18H12X9T electrodes during the first cycle reaches 265–280 mA h/g and that of the reversible capacity ranges up to 185–250 mA h/g during the first 50 cycles. The role of the aluminum collector in the electrochemical transformation of MnO2 has been discussed in thin-layer MnO2/Al electrodes obtained by the mechanical rubbing of the active component into the aluminum matrix. The lithium chemical diffusion coefficient DLi established in the redox reaction of MnO2 with lithium has been estimated in thin-layer composite MnO2 MWCNT/Al electrodes at the current peak values (around 10−12 cm2/s) by slow cyclic voltammetry.