Development of a Single Walled Tank Under Cryogenic Conditions Made of Composite

2018 ◽  
Author(s):  
Philipp W. Kutz ◽  
Frank Otremba ◽  
Jan Werner ◽  
Christian Sklorz
Keyword(s):  
Numerical Simulation ◽  
Liquid Nitrogen ◽  
Test Stand ◽  
Insulation Material ◽  
Insulation Layer ◽  
Temperature Dependent ◽  
Plate Temperature ◽  
Glass Fiber Reinforced Plastic ◽  
Insulation Materials ◽  
Material Values

The use of glass-fiber reinforced plastic (GRP) can reduce the weight of tanks significantly. By replacing steel with GRP in tanks for gases (propane, etc.) a weight reduction of up to 50 % was reached. In this project not only the material should be optimized, but also the design. Previous tanks consist of a double-walled structure with an insulation layer between the two shells (e.g. vacuum). Goal of this project is to realize a single-walled construction of GRP with an insulation layer on the outside. To determine the temperature dependent material values, two different experiments are performed: In the first experiment, temperature dependent material properties of liquid nitrogen found in literature research are validated in a simple setup. The level of liquid nitrogen in a small jar is measured over the experiment time. Numerical simulation shows the change of nitrogen level with sufficient precision. In the second experiment, a liquid nitrogen is applied on one side of a GRP plate. Temperature is measured with thermocouples on top and bottom of the GRP plate, as well as in the middle of the plate. By use of numerical simulation, temperature dependent thermal conductivity is determined. In the third experiment, a test stand is designed to examine different insulation materials. In this test stand, the insulation material can easily be changed. A numerical simulation, in which the determined material data is used, is performed as well for this test stand. The experiments show, that GRP can be used in cryogenic environments. Multiphase simulations are a suitable tool to describe the energy absorption of thermal energy due to thermal phase change. Results on different insulation materials will follow.

Comparative Analysis of the Use of Thermal Insulation Materials Depending on Climatic Conditions and Comfort Microclimate Supply Systems

2022 ◽  
Vol 906 ◽  
pp. 99-106
Author(s):  
Siranush Egnatosyan ◽  
David Hakobyan ◽  
Spartak Sargsyan
Keyword(s):  
Energy Efficiency ◽  
Comparative Analysis ◽  
Thermal Insulation ◽  
Thermal Performance ◽  
Climatic Conditions ◽  
Insulation Material ◽  
Insulation Layer ◽  
Transfer Resistance ◽  
Insulation Materials ◽  
Wide Range

The use of thermal insulation materials to reduce the heating and cooling demand of the building in order to provide energy efficiency is the main solution. But there is a wide range of these products on the market and, therefore, the choice and application of these materials is a rather difficult task, since many factors must be taken into account, such as environmental safety, cost, durability, climatic conditions, application technology, etc. Basically, comfort microclimate systems are designed based on normative standards, where the thickness of the thermal insulation material is selected depending on the required heat transfer resistance. These values are calculated taking into account climate conditions, that is the duration of the heating period, as well as taking into account sanitary and hygienic requirements. This article discusses the thermal performance of building materials, and also provides a comparative analysis of the use of thermal insulation materials depending on climatic factors and on the system providing comfort microclimate. Based on the calculations by mathematical modeling and optimization, it is advisable to choose the thickness of the thermal insulation, taking into account the capital and operating costs of the comfort microclimate systems. Comparing the optimization data with the normative one, the energy efficiency of the building increases by 50-70% when applying the optimal thickness of the thermal insulation layer, and when the thermal insulation layer is increased, the thermal performance of the enclosing structures has improved by 30%, which contributes to energy saving.

Minimization of Heat-Affected Zone Size in Welded Ultra-Fine Grained Steel under Cooling by Liquid Nitrogen during Laser Welding

2007 ◽  
Vol 539-543 ◽  
pp. 4063-4068 ◽  
Author(s):  
Hideki Hamatani ◽  
Yasunobu Miyazaki ◽  
Tadayuki Otani ◽  
Shigeru Ohkita
Keyword(s):  
Laser Welding ◽  
Liquid Nitrogen ◽  
Heat Affected Zone ◽  
Laser System ◽  
Heat Removal ◽  
Plate Temperature ◽  
Fine Grained ◽  
Laser Beam Irradiation ◽  
Average Grain Size ◽  
Plume Temperature

Ultra-fine grained steel (UFGS) with an average grain size of less than 1μm has been developed and is expected to demonstrate superior properties. However, its welded heat-affected zone, HAZ, substantially affecting the strength of a welded joint, will be easily softened after welding. Therefore, minimization of UFGS’s HAZ size during laser welding was carried out using the cooling conductor liquid nitrogen. It was found that a shielding gas with adequate flow rate for the liquid nitrogen depth was used to displace nitrogen on the area of laser beam irradiation to stabilize the weld bead. Also, because YAG laser system was mainly used because it has a lower laser induced plasma or plume temperature, which results in a decreased occurrence of pit and blowhole. HAZ size minimization strongly depends on the initial plate temperature. Reduced initial plate temperature shrinks the specific heated temperature range in which softening occurs. However, due possibly to decreasing thermal conductivity under room temperature, which prevents heat removal, the benefit of reducing the initial plate temperature is limited. The optimal initial temperature to minimize the HAZ size, in the present work, was found to be 123K.

Performance of Nano-Silica Insulation Material Enhanced by High Humidity-Reinforcement Method

2016 ◽  
Vol 697 ◽  
pp. 433-436
Author(s):  
Shi Chao Zhang ◽  
Yu Feng Chen ◽  
Wei Wu ◽  
Hao Ran Sun ◽  
Guang Hai Wang ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Raw Material ◽  
High Humidity ◽  
Insulation Material ◽  
Condensation Polymerization ◽  
Drying Process ◽  
Nano Silica ◽  
Insulation Materials ◽  
The One ◽  
Strength Improvement

In this paper, fumed nano-silica as the main raw material, nano-silica insulation materials were prepared by the dry processing. Research on humidity-reinforcement of nano-Silica insulation materials has been carried out and analyzed. When hygroscopicity of samples reach to 23%, the compressive strength 1.65MPa is at twice the one without high humidity-reinforcement, while the thermal conductivities are almost the same. Then, the action mechanism of high humidity-reinforcement method was analyzed. In humidity-reinforcement method, as vapor enters, silica sol is formed in the gap between one aggregate particle and another, and various condensation polymerization occurred in the drying process, which lead to aggregates connection and compressive strength improvement.

Preparation and Properties of Phase Change Thermal Insulation Materials

2018 ◽  
Vol 281 ◽  
pp. 131-136
Author(s):  
Shi Chao Zhang ◽  
Wei Wu ◽  
Yu Feng Chen ◽  
Liu Shi Tao ◽  
Kai Fang ◽  
...  
Keyword(s):  
Phase Change ◽  
Thermal Insulation ◽  
Calcium Silicate ◽  
Phase Change Materials ◽  
Performance Test ◽  
Thermal Protection ◽  
Insulation Material ◽  
Insulation Materials ◽  
Short Time ◽  
Change Material

With the increase of the speed of vehicle, the thermal protection system of its powerplant requires higher insulation materials. Phase change materials can absorb large amounts of heat in short time. So the introduction of phase change materials in thermal insulation materials can achieve efficient insulation in a limited space for a short time. In this paper, a new phase change thermal insulation material was prepared by pressure molding with microporous calcium silicate as matrix and Li2CO3 as phase change material. The morphology stability, exudation and heat insulation of the materials were tested. The results show that the porous structure of microporous calcium silicate has a good encapsulation when the phase transition of Li2CO3 is changed into liquid. And the material has no leakage during use. The thermal performance test also shows that the insulation performance of the material has obvious advantages in the short term application.

scholarly journals Thermal Performance of Oil Palm Fibre and Paper Pulp as the Insulation Materials

2014 ◽  
Vol 5 (2) ◽  
pp. 22-28
Author(s):  
S.H. Ibrahim ◽  
Sia W.K. ◽  
A. Baharun ◽  
M.N.M. Nawi ◽  
R. Affandi
Keyword(s):  
Thermal Conductivity ◽  
Thermal Performance ◽  
Oil Palm ◽  
Total Density ◽  
Insulation Material ◽  
Paper Pulp ◽  
Particle Board ◽  
Environment Impact ◽  
Palm Fiber ◽  
Insulation Materials

 Energy consumption for residential use in Malaysia is keep increasing yearly in order to maintain the internal thermal comfort of the building. Roof insulation material plays a vital role in improving the thermal comforts of the building while reduce the cooling load of the building. Oil palm industry in Malaysia had grown aggressively over the past few decades. Tons of oil palm waste had produced during the process such as empty fruit bunch fiber. Another waste material that available and easy to obtain is paper. Paper is a valuable material that can be recycled. Waste paper comes from different sources such as newspaper, office and printing papers. This study will take advantage of the available resources which could contribute to reduce the environment impact. The aim of this study is to investigate the thermal performance of roof insulation materials using mixture of oil palm fiber and paper pulp with different ratio and thickness. This study found that the thermal performance of the paper pulp is slightly better compare to the oil palm fiber. Thermal conductivity of the particle board reduces around 4.1% by adding the 10% of paper pulp into the total density of the particle board. By adding 75% of paper pulp, the thermal conductivity of the particle board could be reduced to 24.6% compare to the oil palm fiber board under the similar condition. Therefore, from this study, it could be concluded that paper pulp has high potential to be used as a building insulation material.

scholarly journals Possible Use Of Hemp And Wood In Production Of The Heat Insulation Materials

2015 ◽  
Vol 1 ◽  
pp. 323
Author(s):  
Martins Andzs ◽  
Voldemars Skrupskis
Keyword(s):  
Moisture Content ◽  
Water Absorption ◽  
Heat Insulation ◽  
Raw Material ◽  
Insulation Material ◽  
Heat Transmission ◽  
Insulation Materials ◽  
Wood Fibres ◽  
Heat Insulation Material ◽  
Renewable Raw Material

Obtaining of a new ecological heat insulation material from always renewable raw material in nature, wood and hemp, derived from wood and hemp fibre remains left from the production process. The study was carried out to find hemp wood parts (shives), fiber, and material first possible compositions together with wood fibres, to produce heat insulation materials. The use of the heat insulation material would be meant for dwelling and recreation houses. In the present research the main characteristics of these materials are determined: moisture content, density, water absorption, as well as the coefficient of heat transmission.

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