Investigation of Mechanical Strains in Thermal Compensation Loop of Superconducting NbTi Cable during Bending and Cyclic Operation

In the paper, the thermal compensation loops on a composite, superconducting NbTi cable were investigated. This type of cable is used in the superconducting, fast ramping magnets of the SIS100 synchrotron, part of the Facility for Antiproton and Ion Research (FAIR) under construction in Darmstadt, Germany. The influence of space restrictions and electromagnetic cross-talk on the design of the thermal compensation loop was discussed. Plastic deformation of cable components during bending was analyzed by numerical simulations and experiments. A three-dimensional numerical model of the cable was prepared with individual superconducting wires in contact with a central cooling pipe. The bending of a straight cable into a compensation loop shape was simulated, followed by cyclic operation of the cable during thermal cycles. The maximum strains in the superconducting strands and cooling tube were analyzed and discussed.

Analisa Pipa Heat Exchanger (Cooling Tube) Bervariasi Pada Turbine Guide Bearing Pembangkit Listrik Tenaga Air Siguragura

A heat exchanger is a medium used to produce heat transfer from one fluid to another. Heat Exchanger can be used to raise the temperature or as a heater (regenerator) or lower the temperature or as a coolant (recuperator) depending on the view of heat transfer that occurs. Heat exchangers have been widely used in industries such as the chemical industry, paper industry, power plants, and other industries. In the example, each machine unit uses a heat exchanger media (especially rotary type machines) to keep the bearing temperature in normal temperature even though the unit is operated continuously or continuously. This study will analyze the temperature drop that occurs when the length of the heat exchanger pipe is added to the turbine guide bearing of PLTA Siguragura. From the research results, the maximum temperature on the guide bearing cooling tube reaches 47.3 [° C], the overall heat transfer coefficient on the guide bearing cooling tube is 98.87 [W / m²ºC], ∆Tmin on the guide bearing cooling tube installed (with 2 layers) is 14.1 [° C] and ∆Tmin which can be achieved with a cross-sectional area of ​​5.73 [m²] is 6.63 [° C]

The Effect of Icing on the Output Parameters of the Airflow-Angle Sensor in Case of Failure of the Electric Heating System

At present, with the intensive operation of aircrafts in extremely harsh air conditions, their all-weather use, the work related to improving the flight safety is especially relevant. One of the directions of work in this topic is the study of the types of parametric failures of onboard equipment associated with the influence of the external environment in order to assess their impact on interacting systems and develop recommendations for identifying and countering detected failures. The presented paper considers the results of a full-scale experiment to determine the possibility of operation of the aerodynamic angle sensor in artificially formed icing conditions in case of failure of its electric heating system, as well as a description and results of subsequent modeling of the sensor icing process, and an assessment of its effect on the accuracy characteristics of the sensor output signal. The statement of the research problem is formulated as follows: it is necessary to ensure the testing of the sensor and the subsequent processing of the results obtained in order to form a generalized mathematical model of the sensor icing process, as well as to solve the problem of introducing additional errors into the sensor signals, which makes it possible to study the behavior of air signal systems using vane sensors of aerodynamic angles with artificially introduced failures. A full-scale experiment was carried out in an air-cooling tube on the basis of the enterprise JSC "UKBP". Numerical modeling and determination of correction factors were carried out in the software packages Ansys FENSAP ICE and MathCAD. Analysis of the results achieved in the course of modeling confirmed the convergence of the model obtained with the data of real experiments in an air-cooling tube. The data obtained made it possible to confirm the possibility of detecting distorted values for the angle of attack by the parametric quorum control method.

Thermal Analysis of Wavy Thermal Management System With Phase Change Composite and Pyrolytic Graphite Sheet for Cylindrical Lithium-Ion Battery Packs

In the present study, a wavy designed thermal management system (TMS) is introduced for cylindrical lithium-ion battery pack modules incorporating a phase change composite (PCC) surrounding the cells, a cooling tube, and a pyrolytic graphite sheet (PGS) integrated into the wavy design on both sides of the cooling tube. We systematically investigate its cooling behavior via thermal analysis in Ansys FLUENT. This thermal management system takes advantage of the PCC’s capabilities to maintain temperature uniformity and PGS’s thermal conductivity to increase the rate of heat removal. The 1S20P battery pack design was simulated at different cell volumetric heat generation rates from normal to uphill conditions to observe cooling capabilities under different thermal loads.

A Conjugate Heat Transfer and Thermal Stress Analysis of Film-Cooled Superalloy With Thermal Barrier Coating

A conjugate heat transfer study is carried out to obtain temperature and thermal stress field of a film-cooled superalloy with multi-layer thermal barrier coatings (TBCs). The aim is to understand the effects of the blowing ratio and ceramic top coating (TC) thickness on temperature and thermal stress which have an influence on component reliability and life. Results reveal that the distribution of film cooling effectiveness gets more uniform as TC thickness decrease because thick TC with low thermal conductivity prevents heat conduction in the axial and spanwise directions. In the upstream of the film cooling hole, the cooling effect is enhanced nonlinearly with the increase of the blowing ratio since the flow separation in the cooling tube affects the heat transfer enhancement. The insulation performance is improved by about 10 K for every 0.1D increase in TC thickness and the cooling effect is improved by about 20 K when the blowing ratio is increased from 0.5 to 1.0 at the leading edge of the film-cooling tube. The influence of jet lift-off and hotgas entrainment on the insulation effect is greater than TC thickness. The stress is concentrated at the leading edge of the film cooling hole and interfaces of TBCs. The maximum Von-Mises stress (761 MPa) on the interfaces is not at the leading or trailing sides of the film-cooling tube, it is about ± 45° from the centerline of the BC/SUB interface. The debonding stress at TC/BC interface and BC/SUB interface are about 26 MPa and 175 MPa respectively. The normal stress near the film-cooling tube on the BC/SUB interface is 5 – 7 times the one at TC/BC interface. Therefore, the interface crack is more likely to initiate at the BC/SUB interface, and the crack may keep growing and cause the spalling of TBC.