Best Determined Position of Vents Based on Jet Cooling Model

In some data centers,cold air is required to act on the cabinet to achieve cooling requirements,and the mixing of cold air and hot air reduces the utilization efficiency of cold air.In order to solve this problem,a jet cooling model is established to solve the optimal position of the outlet through the movement of cold air.

On the Method of Air Jet Cooling in Green Manufacturing

Green cooling is an important technology in green manufacturing. In the way of jetting, cooling airflo-w in used in the experiments of metal material cutting, by comparison of the changes of some technological factors, such as cutting heat, surface finish, in the process of jet cooling, pour cooling and natural cooling, we can draiv the conclusion that air jet cooling has a better cooling effect and green function. It can be 'widely used in both traditional and automatic green manufacturing.

Application of difference arithmetic in the continuous annealing process line cooling control at Baosteel

Some of the main cooling processes and equipment that are currently being used in the continuous annealing process line （CAPL） at Baosteel are introduced, as well as their cooling control model techniques, the modeling principium and their application results. With charts indicating the control trends in real processes, the powerful adjusting ability of the control models with process variable differences and their excellent control precision are shown in this study.

Numerical Investigation of Jet Impingement Cooling with Supercritical Pressure Carbon Dioxide in a Multi-Layer Cold Plate during High Heat Flux

Jet impingement cooling with supercritical pressure carbon dioxide in a multi-layer cold plate during the heat flux of 400 W/cm_(2) is investigated numerically.The generation and distribution of pseudocritical fluid with the high specific heat of supercritical pressure carbon dioxide and the mechanism of the heat transfer enhancement led by the high specific heat are analyzed.For a given nozzle diameter,the effects of the geometric parameters of a multi-layer cold plate such as the relative nozzle-to-plate distance,relative plate thickness,and relative upper fluid thickness on the average heat transfer coefficient are studied.The results show that the target surface is cooled effectively with supercritical pressure carbon dioxide jet impingement cooling.When the radial distance is less than 6 mm,the maximum wall temperature is 368 K,which is 30 K lower than the maximum junction temperature for a silicon-based insulated gate bipolar transistor,a typical electronic power device.There is a pseudocritical fluid layer near the target surface,where specific heat reaches above 34 kJ/(kg·K)locally.The drastic rise of the specific heat leads to obvious heat transfer enhancement.Within a certain range,the local heat transfer coefficient and the specific heat are linearly correlated and Stanton number remains constant over this range.The heat transfer coefficient is at a maximum when the relative nozzle-to-plate distance is 1.As the relative plate thickness increases from 0.5 to 3.5 or the relative upper fluid thickness increases from 0.5 to 2.5,the average heat transfer coefficient decreases monotonically.

Machinability of ultrasonic vibration-assisted micro-grinding in biological bone using nanolubricant

Bone grinding is an essential and vital procedure in most surgical operations.Currently,the insufficient cooling capacity of dry grinding,poor visibility of drip irrigation surgery area,and large grinding force leading to high grinding temperature are the technical bottlenecks of micro-grinding.A new micro-grinding process called ultrasonic vibration-assisted nanoparticle jet mist cooling(U-NJMC)is innovatively proposed to solve the technical problem.It combines the advantages of ultrasonic vibration(UV)and nanoparticle jet mist cooling(NJMC).Notwithstanding,the combined effect of multi parameter collaborative of U-NJMC on cooling has not been investigated.The grinding force,friction coefficient,specific grinding energy,and grinding temperature under dry,drip irrigation,UV,minimum quantity lubrication(MQL),NJMC,and U-NJMC micro-grinding were compared and analyzed.Results showed that the minimum normal grinding force and tangential grinding force of U-NJMC micro-grinding were 1.39 and 0.32 N,which were 75.1%and 82.9%less than those in dry grinding,respectively.The minimum friction coefficient and specific grinding energy were achieved using U-NJMC.Compared with dry,drip,UV,MQL,and NJMC grinding,the friction coefficient of U-NJMC was decreased by 31.3%,17.0%,19.0%,9.8%,and 12.5%,respectively,and the specific grinding energy was decreased by 83.0%,72.7%,77.8%,52.3%,and 64.7%,respectively.Compared with UV or NJMC alone,the grinding temperature of U-NJMC was decreased by 33.5%and 10.0%,respectively.These results showed that U-NJMC provides a novel approach for clinical surgical micro-grinding of biological bone.