Optimization of the pultrusion process for a rod with a large diameter

A technique of the optimization of the pultrusion process for rods with a large diameter with the use of methods of mathematical modeling is described. An example of the search for the optimum technological parameters for the pultrusion of a glass-plastic rod with a diameter of 80 mm is presented.     

Thermoanemometric transducer of pressure derivative

Conclusions The lower limit of the range of the transducer of p is given by the permissible reduction in the device sensitivity due to convection at low flow velocities while the upper limit is given by a reduction in the thermoanemometer sensitivity caused by an increased flow velocity. The static characteristic of the instrument is to a considerable extent nonlinear because of the nonlinearity of the thermoanemometer.The transducer time constant is the resultant of two components: of the time constant of the chamber and channel (pneumatic component) and the time constant of the thermoanemometer (thermal component). In the case of correctly selected chamber and channel components the time constant of the thermoaneommeter may be assumed to remain constant over the entire measurement range, being dependent only on the dynamic properties of the selected thermistor and on the coefficient of negative feedback in the system T=const. The time constant of the penumatic part of the instrument is determined by the upper and lower limits of the thermoanemometric device measuring p at the given sensitivity threshold of the thermoanemometer.The temperature and density errors of the transducer are large and necessitate the use of special compensating devices if the instrument is to be used over a wide temperature and pressure range.Translated from Izmeritel'naya Tekhnika, No. 1, pp. 45–48, January, 1973.     

Calculation of the kinetics of steel austenization in laser heating

We examine both the kinetic features and the present the formulation of the problem dealing with the distribution of carbon concentrations in an austenite, as well as the motion of the phase separation boundaries in the case of laser heating of pre-, post-, and eutectoid steels. We also obtain results from calculations carried out on a number of laser treatment regimes on eutectoid steel.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 57, No. 6, pp. 959–964, December, 1989.