[en] A calorimetric method for measuring liquid helium flow rate is treated. The system is implied for measuring single-phase helium ranging from 3 to 50 g/s. The main measuring error is 6%. The flowmeters design, measuring apparatus and software are described. The influence of the measured parameters errors on the accuracy of helium flow rate measuring has been analyzed

[en] A calorimetric method for measuring stationary and non-stationary heat release in the UNK superconducting magnets during cryostating in a circulating mode is considered. Measurement errors are analyzed. The results obtained when measuring heat release in models of the UNK superconducting dipoles are presented. The developed calorimetric method permits to determine superconducting magnet heat release deposited on the cryogenic system with an error not more than 11%. Such accuracy is attained by using one thermotransducer for measurements. In contrast to the known electrical methods the given method can be applied for measuring heat release by different components of the magnetic cycle

[en] The results of the experimental investigations for cooldown to 4.5 K and warmup precesses in the single 6 m SC dipole magnet of the UNK with a cold iron are presented. The temperature distributions were measured with 232 temperature sensors arranged in 14 cross sections of the dipole. Both usual cryogenic technological processes and regimes connected with the SC magnet transition into a normal state were investigated. 3 refs.; 9 figs

[en] Consideration is being given to a multichannel system for measurement and control of vacuum designed for the cryogenic benches for testing superconducting magnets of the IHEP accelerating-storage complex. The basic system module is the eight-channel unit for measurement and control of vacuum. The system comprises as well supply and indication units. Eight-channel unit for measurement and control of vacuum is composed of eight similar control channels. Each channel comprises current stabilizer, amplifier and comparator. The unit includes as well the source of standard voltage common for all eight channels. Test operation of the system for measurement and control of vacuum demonstrated its high operating properties. The system has small dimensions, is convenient in service. Operability of vacuum state control was increased sufficiently. The system is easily connected with the common system of data collection and processing created on the base of the SM-4 computer

[en] The computational method is presented for the 3-dimensional nonstationary temperature field in the UNK SC dipole during its cooldown from 290 to 4.5 K. The method uses 1-dimensional equations for gas and a 2-dimensional heat conductivity equation for the dipole cross-section. The latter equation takes into account the interplay between the elements along the longitudinal axis. The temperature distributions were used in determining the thermomechanical stresses in the helium cryostate tubes. The computational results are compared with experimental data. 9 refs.; 6 figs

[en] The results of numerical analysis of heating processes in the cross section of the accelerating-storage complex superconducting (SC) dipole in cooling down and heating up modes are presented. The influence of the heat transfer coefficient and thermal resistance between the windings and the yoke on the duration of heating processes in the dipole has been investigated. The peculiarities of the temperature field in the SC-dipole cross section have been exhibited and the temperature drops in the units are quoted

[en] The total heat load and the heat leak through the support to the helium vessel of the superconducting dipole have been studied. The technique applied to study these heat loads are presented. The measured value of the heat load is 5-6 W, 1 W falls at the supports. The experimental results obtained are compared with calculational estimates and feasibilities for a further reduction of a heat load to the helium vessel of the magnet are discussed. 8 refs.; 4 figs.; 1 tab

[en] A calorimetric flow meter of single-phase liquid helium in the 0.003-0.050 kg/s range is described. For measuring temperature differences one thermometer placed behind a heater is used that leads to decreasing the flow measurement error on slight flow heating. The flow measurement error is about 6 %, when flow is heated by approximately 0.05 K, single measurement time is about 12 s

[en] The computational method is presented for the 3-dimensional nonstationary temperature fields in the UNK superconducting dipole magnet during its cooldown from 290 to 4.5 K. The method uses 1-dimensional equations for gas and a 2-dimensional heat conductivity equation for the dipole cross-section. The latter equation takes into account the interplay between the elements along the longitudinal axis. The temperature distributions were used in determining the thermomechanical stresses in the helium cryostat pipes. The computational results are compared with the experimental data. (Author)

[en] Investigation of processes of cooling and heating of superconducting (SC) accelerators is related both with the choice of the scheme and equipment of cryogenic supply system and with determination of structural strength of accelerator units after temperature gradients occur in them. Longitudinal arm size of SC magnets in the UNK exceed sufficiently the cross size. This enables to study separately longitudinal and transverse thermal processes and then to consider mutual errors when analyzing cooling and heating processes in general. Calculation of conditions of cooling and heating of the UNK SC dipoles with cold yoke was conducted for two technological periods: scheduled one, when all the UNK magnets are cooled and repair one, when heating and cooling is conducted only for the group of magnets, which contains poor magnet. Technique for calculating temperature field in the cross section of SC dipole is based on solution of two-dimensional parabolic heat conduction equation for nonstationary case with regard to structural peculiarities of SC magnet. Finite element method with the use of implicit circuit (modified HAST package) was applied for the solution