Seeds of success in a water jacket

Author(s):  
Andrew Scott
Keyword(s):  
2021 ◽  
Vol 11 (15) ◽  
pp. 6749
Author(s):  
Zhifeng Xie ◽  
Ao Wang ◽  
Zhuoran Liu

The cooling system is an important subsystem of an internal combustion engine, which plays a vital role in the engine’s dynamical characteristic, the fuel economy, and emission output performance at each speed and load. This paper proposes an economical and precise model for an electric cooling system, including the modeling of engine heat rejection, water jacket temperature, and other parts of the cooling system. This model ensures that the engine operates precisely at the designated temperature and the total power consumption of the cooling system takes the minimum value at some power proportion of fan and pump. Speed maps for the cooling fan and pump at different speeds and loads of engine are predicted, which can be stored in the electronic control unit (ECU). This model was validated on a single-cylinder diesel engine, called the DK32. Furthermore, it was used to tune the temperature of the water jacket precisely. The results show that in the common use case, the electric cooling system can save the power of 255 W in contrast with the mechanical cooling system, which is about 1.9% of the engine’s power output. In addition, the validation results of the DK32 engine meet the non-road mobile machinery China-IV emission standards.


2020 ◽  
Author(s):  
Ji Liu ◽  
Yan-Hua Zhou ◽  
Xiao-Xiao Wang ◽  
Ling-Xi Tong ◽  
Yan-Hong Li ◽  
...  

Abstract Background: Different types of incubators have been designed for gamete and embryo culture in the past few years. The main differences of these incubators are humidity, temperature and gas control system, which play important roles in regulating the steady state of culture media. The objective of this study was to compare the effects of different types of incubators (air jacket incubators and water jacket incubators) on embryo development and clinical outcomes in human in vitro fertilization (IVF).Methods: First, the physical performances of different incubators were tested by mimicking routine IVF procedures. After that, in a randomized controlled trial, 1013 cumulus oocyte complexes from 43 patients were equally divided into two groups, fertilized and cultured in two types of incubators to analyze the effects of different types of incubators on embryo development and clinical outcomes. Results: We found that temperature recovery time in the air jacket incubator was significantly shorter than that in water jacket incubator. Although the O2 recovering time was also significantly shorter in the air jacket incubator as compared with the water jacket incubator, no significant differences were observed in the CO2 recovering time between two groups, which was also verified by pH recovering time of culture media. Besides, the temperature of culture medium in the dish covered with oil recovered more quickly in the air jacket incubators than that in water jacket incubators. However, there were no significant differences observed in the fertilization rate, Day 3 high-quality embryo formation rate, blastocyst formation rate, good blastocyst rate and clinical outcomes between two groups.Conclusions: These results indicate that the microenvironment, especially the temperature, in air jacket incubator recover faster than that in conventional water jacket incubator, however, there were no significant differences in embryo development and clinical outcomes between two types of incubators.


2012 ◽  
Vol 7 (23) ◽  
pp. 435-441
Author(s):  
Qi Lili ◽  
Zhang Cuiping ◽  
Qi Dongdong ◽  
Zhang Zhongguo ◽  
Li Tianpeng

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1967 ◽  
Author(s):  
Bishal Silwal ◽  
Abdalla Hussein Mohamed ◽  
Jasper Nonneman ◽  
Michel De Paepe ◽  
Peter Sergeant

Thermal loading can induce mechanical stresses in the windings of electrical machines, especially those impregnated with epoxy resins, which is mostly the case in modern traction motors. Although designers look for cooling techniques that give better performance in terms of the power density and efficiency of the machine, several thermal cycles can lead to fatigue and the degradation of the copper insulation, epoxy and consequently the windings. In this paper, the performance of different cooling techniques has been compared based on the temperature distribution and the mechanical stress induced in the windings. Three-dimensional finite element thermo-mechanical models were built to perform the study. Two different variants of water jacket cooling, two configurations of direct coil cooling and two cases of combined water jacket and direct coil cooling methods have been considered in the paper. The results show that the combined water jacket and direct coil cooling perform the best in terms of the temperature and also the mechanical stress induced in the windings. An experimental set-up is built and tested to validate the numerical results.


Having undertaken the investigation of the absorption spectra of metals in a state of vapour, the first substance examined was mercury, and as the results are interesting I have deemed it advisable to make them a separate communication to the Society. F. P. le Roux describes the vapour of mercury as having a bluish colour, and according to R. J. Strutt, it transmits a feeble steel-blue colour, but the absorption coefficient is small. Experimental.—The substance to be volatilised was contained in a flask of Heraeus’ quartz-glass, with a side tube to the neck from which the metal may be distilled and condensed. To the side tube a water-jacket is fitted through which a constant stream of water may be passed if necessary. The rays from the condensed spark of a pair of lead-cadmium and tin-cadmium electrodes were passed through the flask and on to a cylindrical condensing lens of quartz which focussed the rays on to the slit of a quartz spectrograph.


2019 ◽  
Vol 9 (4) ◽  
pp. 621 ◽  
Author(s):  
Samira Uharek ◽  
Sara Baratchi ◽  
Jiu Zhu ◽  
Majed Alshehri ◽  
Arnan Mitchell ◽  
...  

Water jacket systems are routinely used to control the temperature of Petri dish cell culture chambers. Despite their widespread use, the thermal characteristics of such systems have not been fully investigated. In this study, we conducted a comprehensive set of theoretical, numerical and experimental analyses to investigate the thermal characteristics of Petri dish chambers under stable and transient conditions. In particular, we investigated the temperature gradient along the radial axis of the Petri dish under stable conditions, and the transition period under transient conditions. Our studies indicate a radial temperature gradient of 3.3 °C along with a transition period of 27.5 min when increasing the sample temperature from 37 to 45 °C for a standard 35 mm diameter Petri dish. We characterized the temperature gradient and transition period under various operational, geometric, and environmental conditions. Under stable conditions, reducing the diameter of the Petri dish and incorporating a heater underneath the Petri dish can effectively reduce the temperature gradient across the sample. In comparison, under transient conditions, reducing the diameter of the Petri dish, reducing sample volume, and using glass Petri dish chambers can reduce the transition period.


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