PSI - Issue 50

V.V. Titkov et al. / Procedia Structural Integrity 50 (2023) 284–293

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Titkov V.V. et al./ Structural Integrity Procedia 00 (2019) 000 – 000

Fig. 2. Model of elastic-plastic deformation.

The temperature field is described by the equation of thermal conductivity with a heating source in the form of a Joule heating: 2 ( ) / T c T H j t           . (5) 3. Numerical work As a typical example, consider a single-turn solenoid made of steel with internal and external diameters of 20 mm and 100 mm with a length of 50 mm. The solenoid is affected by a current pulse, which is the first half-period of the sinusoidal function, which is in a good agreement with the conditions of the aperiodic discharge of the current source. The corresponding induction pulse in the working volume of the solenoid can be characterized by the amplitude Bm and the duration Tp corresponding to the half-period of the sinusoidal function (Fig. 3). The order of magnitude of the stresses caused by electromagnetic forces can be estimated using the formula for "magnetic" pressure: 2 2 0 Bm P    . (6) Typical values of induction that create magnetic pressure above the yield strength of structural metals and alloys are Bm = 20 – 30 T Fig. 3 and 4 show the distribution of magnetic field induction, electromagnetic forces and the shape change of the section of a single-turn solenoid made of stainless steel 20X13H4G9 when exposed to a unipolar pulse with a duration of 100 microseconds.