Applied Mechanics and Materials Vols. 716-717

Abstract: The gas flow in the cold storage plays a very important role in the effect of cold storages of procambarus clarkii. Only the reasonable gas flow ensures the uniform temperature field.The paper uses the technique of computational fluid dynamics (CFD) to conduct the numerical simulation of the flow field and finds out the law of the distribution of the temperature field,on the basis of which the numerical simulation of non steady state of the freezing process of the frozen products is carried out.The experiments prove that the simulation results can better reflect the reality,and show that CFD tools can play an important role in the design and optimization of cold storages.

Abstract: Predicting thermoelastic damping is essential in the design of the next generation of layered composite microresonators. We present an analytical model for thermoelastic damping in circular microplates using the framework developed by Bishop and Kinra. The thermoelastic damping spectrum will exhibit two distinct peaks when the thermal conductivity of the substrate is much greater or less than that of the film. Increment of the thickness of a layer with the bigger Zener’s modulus will increase the peak damping.

Abstract: In order to study the feasible floating roof tank lighting protection technology, this paper put forward making oxygen concentration remain below 8% through inerting sealed space, thus reduces fire risk. By analyzing the oxygen concentration change after injecting nitrogen into the sealed space, sets up the relationship between the oxygen concentration change and nitrogen injection volume. Mean while, through the experiment when the sealed space maintains the micro positive pressure, established a formula about the nitrogen flow and micro positive pressure, which can obtain nitrogen amount directly under different wind velocity and lightning time to complete inerting. Finally, design a nitrogen protection system which can protect lighting fire, and can put out floating roof tanks initial fire.

Abstract: In this paper, the scattering parameters of aerosol particles are calculated based on Gamma model of atmospheric particle size distribution and the Mie scattering theory for 0.53μm、1.06μm and 10.6μm laser. For the transmission attenuation of the laser in aerosol, the Monte Carlo simulation model is established. The transmittances with propagation distance are calculated for three kinds of wavelength laser in the continental, marine and cumulus aerosols respectively. The results show three kinds of wavelength laser transmission attenuation in cumulus clouds are far stronger than in the continental and marine aerosol. The transmission performance of 10.6μm laser is best in continental aerosol. For marine aerosol, the attenuation to 0.53μm laser is stronger than to 1.06μm and 10.6μm.

Abstract: Absorption refrigerator is not a new concept. It provides advantages of being silent, of having no compressor, which also makes it lasting a long life cycle. Particularly, it can utilize low level waste energy. In this contribution, a 2-fluid aqua-ammonia prototype is analysed and an overall design and construction procedure of a mini-type, 3-fluid absorption refrigerator is given, with working fluids of organic compounds (R134a as refrigerant and Tetraethelene Glycol Dimethyl Ether as absorbent) and a pressure balancing gas. The aim of this project is to develop a potential mini-type cooling system for rural areas, where electricity is scarce or non-existed. The experiments showed the combination of R134a and TEG.DEM for mini-type solar absorption refrigeration is theoretically realisable; To have an ideal performance, except of interfusion of non-condensable gas and impermeability of the system, the filling methods, vacuum drawing state as well as the stability of input power are all crucial influence factors.

Abstract: Because of the advantage on energy saving and environmental sustainable development, the ground source heat pump (GSHP) system has received the widespread attention and application in recent years.However,the difference between cooling load in summer and heating load in winter is obvious in most areas of our country,so it can cause the heat accumulation around ground heat exchanger,which will result in degradation of system performance and increment of system operating costs.To solve the problem of thermal imbalance,it is necessary to research the soil temperature field around the buried pipes in the process of system operation.This paper begins with a review of the studies about the ground source heat pump systems.This is followed by a review of various methods of enhancing the performance of heat pumps based on the thermal imbalance.And then,this paper shows some studies about ground source heat pump systems based on the groundwater seepage.

Abstract: When the high-pressure chemical oxygen delivery device, the slightest mistake, likely to cause explosion, so the design oxygen pipeline, it is usually as a special danger medium piping design. This paper explores the design of the petrochemical industry in oxygen pipes, installation and construction unit issues and process piping installation and construction issues, systematic analysis of the piping in the design and construction should pay attention to the problems and solutions to ensure each petrochemical industry aspects of safe operation. Standard requirements and corresponding measures in aspects of oxygen pipeline flow rate control, material selection, pipe and valve selection and pipeline construction, which should be followed to ensure the safety of oxygen pipeline, which are described in details, according to the national standard/safety technical regulation for oxygen and relative gases produced with cryogenic method. Finally, the experience of safe use of oxygen pipelines is presented.

Abstract: Lower biomass briquette fuel Combustion efficiency for Stream-chain Boiler furnace burning dyeing factory,the existing Furnace arch configuration easily lead the front burning,easy to burn coal gate and ignite fuel bin.Proposed through the transformation of traditional industrial boiler feed systems,before and after the boiler arch configuration,add dedusting equipment,add the secondary air system and adjust primary air supply system to improve the boiler,which can effectively improve the combustion efficiency,to solve the question of coal gate back burning bad front wall and ignite fuel bin.Ease dust accumulation and slagging problems in the biomass boiler.

Abstract: If finite element models for beam structures of the rail weld CNC fine milling machine are built, and static analysis and modal analysis are used to model the beam structure, it can be concluded that the beam has sufficient margin in strength but lower stiffness. The beam structure is optimally designed with orthogonal test. After optimization, the beam body has been obviously improved in stiffness, and reduced lightly in weight.

Abstract: With the rapid development of industry, the status of the eutrophication of water is becoming more and more serious. The result is that water blooms and the environment becomes worse. In order to resolve this question ,ShangHai Ocean University designed a small aquatic harvester. According to the vibration problem on the research of the transmission system of the small aquatic harvester , the text has given suggestions on how to reduce the vibration problems after taking theoretical analys from the angle of assembly error.