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The article discusses a mathematical model of the electrothermal process of heating the formation with a microwave electromagnetic wave, which is caused by electrical devices capable of operating under high pressure. The issues of using microwave dielectric heating to reduce the viscosity of oil-bearing deposits, which will increase the efficiency of their production, are considered. The article presents an in-depth analysis of various existing and promising methods of ensuring the production of high-viscosity oil and shows the advantages of the thermal method, and on the basis of calculations using mathematical and computer models-the prospects for using microwave radiation. Models of the electromagnetic field are shown that provide uniform heating of the sediment to a sufficient depth. The results of the work create and substantiate the basis for the development of a new technology for thermal increase in the efficiency of oil production, primarily in combined oil fields and northern regions, which are characterized by high oil viscosity.

Analytical relationships for determining the sensitivity of a vibration acceleration transducer with a spiral secondary element are given. Computations using these relationships are compared to the results of experimental investigations.

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Solution of the problem. A comparative analysis of control methods for the presence of SCCs in trans formers is possible as a result of analytical studies based on a mathematical model.In order to empirically confirm the analytical conclusions, we studied a model of a transformer converter (an electromagnetic cannon) with various coil attachments ( Fig. 1) for demonstration of the presence of SCCs in the windings of a transformer [1] and the conductance of comparative experimental studies.For the comparative analysis, we considered the transformer in the idling and short circuit modes, which allowed us to compare the changes in the inductivity and Q factor in the construction of the trans former during the mathematical modeling. Figure 2 shows a substitution scheme of the transformer (TM) in the idling mode, which includes active resistance of the winding, r 1 , and resistances the correspond to losses in the magnetic circuit Rμ and inter induction in windings, L. The resulting inductivity, L p1 , and Q factor (magnetic Reynold's num ber), ξ fp1 , which characterizes the intensity of electromagnetic processes in the TM, can be determined for this substitution scheme of the TM.During mathematical modeling, the following initial expressions were obtained:(1)where ξ f1 = and ξ f2 = are the Q factors of the magnetic circuit and windings, respectively; ω is the cyclic frequency of the alternating current; L is inductivity; and ξ f is the magnetic Reynold's number (Q factor).For the comparative analysis we considered a TM model that includes a short circuited electro con ducting coil (SCC), which corresponds to reduced resistance of the secondary winding (SCC winding) in the TM substitution scheme (Fig. 3).In order to characterize the SCC, the number K = W k /W is introduced, viz., the coefficient of SCC transformation, where W k is the number of SCC coils and W is the number of winding coils. MAGNETIC AND ELECTRICAL METHODSAbstract-One of the most characteristic defects in the manufacture of transformers during mass pro duction is the presence of short circuited coils (SCCs) in windings. The advantages of a method for the control of this defect via measurements of the Q factor in relation to industrially used analogous control methods based on measurements of inductivity or losses in a transformer is shown on the basis of a mathematical model and analytical studies. An experimental apparatus for the empirical testing of the main theoretical concepts is developed. The degree of change of inductivity and Q factor values of a transformer depending on the proper ties of the magnetic circuit material and the presence of a short circuit in transformer windings were determined.