Thermal physical parameters such as specific heat and heat diffusion coefficient were definitely obtained with transient method in which surface temperature variation of a thin Pt wire within a ...transient period was measured and the measured results were imitated by least square principle. Effectiveness of the method was certified in the case of glycerin. While the method was applied to mineral oil VG46, it was found that there was very weak temperature dependence of thermal parameters for mineral oil VG46 at normal temperature.
There are large quantities of waste-heat produced in the machining process of cartridge type structures(58SiMn steel), it is necessary to recycle and make full use of these heat from the perspective ...of environmental protection and energy saving. We will study the possibility of using the recalled calories to privide bath water for workers and the compensate water for steam boilers. In this paper the waste heat recovery system that based on heating pump were analyzed, including the system composition, working principle, the thermal parameters, etc. According to the technique characteristics of hot pump and making use of thermodynamics mechanism we carried on analysis and calculation about the lost thermal energy in the medium repeatedly heat machine, the power of medium repeatedly. We can make 17.33 ton hot water which is 55 Celsius degree per hour using the recalled calories. These hot water can provide the nedding water for the steam boilers and the workers bathing. This research show that waste heat recovery system which is used in the production of the cartridge type structures is effectual.
Recent results from seismic tomography reveal that configurations of the subducted slabs are varied; some of them lie horizontally on the boundary between the upper and the lower mantles, and others ...penetrate into the lower mantle. In this study, a two-dimensional model which gives the velocity boundary condition is constructed to investigate temperature distribution in and around the horizontally lying slabs. The model includes the effect of flow of the ambient mantle induced by the subducting slab. The length of the horizontally lying portion of the slab tends to be proportional to the subducting velocity, and to approach a constant value with increasing dip angle. These suggest that the length of the horizontally lying portion of the slab is subject to the thermal parameter. P-wave velocity anomalies converted from the calculated temperature distribution nearly at steady state show region with very high velocity anomaly, more than 10%, within the slab, which is different from the results of seismic tomography. This indicates that our assumption that the mantle material is composed of olivine (Mg0.89Fe0.11)2SiO4 may not be correct, or the approximation of the used equations of state may not be so rigorous. We also found that the horizontally lying slabs calculated in this study exist at the region with high velocity anomalies in the seismic tomography. Furthermore, our result indicates that the viscous heating in the ambient mantle should be necessary to keep the mantle wedge hot permanently under the condition without upwelling and/or inflow of hot material.
In order to promote circulating fluidized bed (CFB) 1, the pressure and temperature of the steam and the boiler capacity should be increased, and this idea is realized widely in the world. The ...maximum capacity 330 MW CFB boiler in China is developed and operates since 01.09.2008. The boiler is designed by Chinese self-technology. The main parameters are researched and determined, boiler general arrangement is introduced, the design of the boiler key parts is researched, at last, the boiler operating are introduced in this paper. It can be considered when Chinese self-technology supercritical CFB boiler is developed.
Debye-Wallerov termički parametar B je mjera srednje-kvadratne amplitude atomskog titranja hu2i. Za monoatomske kubne kristale, koji pokazuju isotropno titranje, B = 8πhu2i/3. U ovom se radu pokazuje ...kako se niz metalurških svojstava, npr., čvrstoća, temperatura pojave plastične deformacije, temperatura rekristalizacije, aktivacijska energija za difuziju kroz granice kristalića, granica topivosti i druga, elemenata kubne strukture, mogu prikazati jednim izrazom kao funkcije njihovih B-faktora. Regresijska relacija Y = Y0(B/B0)M daje tu korelaciju metalurškog svojstva i Debye-Wallerovog termičkog parametra B. Regresijski koeficijent Y0 i regresijski eksponent M određuju se metodom najmanjih kvadrata, dok je B0 konstanta kojom se postiže dimenzijska homogenost relacije.
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