scholarly journals Heat and Moisture Modelling of Vacuum Insulated Retrofits with Experimental Validation

2021 ◽  
Vol 2069 (1) ◽  
pp. 012035
Author(s):  
B Conley ◽  
C A Cruickshank ◽  
C Baldwin

Abstract Vacuum insulation panels (VIPs) offer 8-10 times the thermal resistance of fiberglass insulation and would fit the need for a low conductivity exterior insulation. A composite insulation panel using VIPs encased in rigid foam was developed, built, and tested. Two different sizes of VIPs were used for that stage of the project, and after monitoring and evaluation, they showed contrasting results. A simulation study was performed to find the optimal VIP solution that maximized the effective thermal conductivity and minimized the mould growth potential. In total, 5 wall assemblies with VIPs used as the exterior insulation were simulated using WUFI and WUFI2D. The simulations showed that the humidity levels at the inside face of the OSB inboard of the VIPs decreased when 200 mm by 300 mm VIPs were used, but they did not reach the thermal performance thresholds of R5.28 m2K/W. The hygrothermal analysis showed that under similar conditions, a VIP insulated wall assembly would have a lower relative humidity at the sheathing surface compared to EPS and XPS. The one-and two-dimensional simulations were compared and found that WUFI Pro was capable to evaluate a VIP-insulated wall assembly.

2020 ◽  
pp. 174425912098003
Author(s):  
Travis V Moore ◽  
Cynthia A. Cruickshank ◽  
Ian Beausoleil-Morrison ◽  
Michael Lacasse

The purpose of this paper is to investigate the potential for calculation methods to determine the thermal resistance of a wall system containing vacuum insulation panels (VIPs) that has been experimentally characterised using a guarded hot box (GHB) apparatus. The VIPs used in the wall assembly have not been characterised separately to the wall assembly, and therefore exact knowledge of the thermal performance of the VIP including edge effect is not known. The calculations and simulations are completed using methods found in literature as well as manufacturer published values for the VIPs to determine the potential for calculation and simulation methods to predict the thermal resistance of the wall assembly without the exact characterisation of the VIP edge effect. The results demonstrate that disregarding the effect of VIP thermal bridges results in overestimating the thermal resistance of the wall assembly in all calculation and simulation methods, ranging from overestimates of 21% to 58%. Accounting for the VIP thermal bridges using the manufacturer advertised effective thermal conductivity of the VIPs resulted in three methods predicting the thermal resistance of the wall assembly within the uncertainty of the GHB results: the isothermal planes method, modified zone method and the 3D simulation. Of these methods only the 3D simulation can be considered a potential valid method for energy code compliance, as the isothermal planes method requires too drastic an assumption to be valid and the modified zone method requires extrapolating the zone factor beyond values which have been validated. The results of this work demonstrate that 3D simulations do show potential for use in lieu of guarded hot box testing for predicting the thermal resistance of wall assemblies containing both VIPs and steel studs. However, knowledge of the VIP effective thermal conductivity is imperative to achieve reasonable results.


Competitio ◽  
2020 ◽  
Vol 10 (2) ◽  
Author(s):  
Oliver Kovacs

This contribution addresses the question of what are the main constituents of an innovative fiscal policy in the context of sustainability. We apply the concept of sustaining and disruptive innovation to fiscal policy. On the one hand, innovative fiscal policy is able to be sustaining whereby public finance will incrementally improve without leaving its decisive structure. On the other hand, innovative fiscal policy should be disruptive as well in the context of long term sustainability, whereby the structure of public finances can be profoundly restructured as a reaction to future challenges. By using the Finnish recovery in the early 1990s, we can refine our argument about the use and necessity of the mixture of fiscal rules and independent institutions in favour of fiscal sustainability. We also shed light on the key sources of the expansionary consolidation that emerged in the aftermath of the fiscal adjustment in the early 1990s. We emphasise that innovative fiscal policy with a mixture of legislated fiscal rules and independent fiscal anchor is more likely to be associated with sustainability if the economy has weaker growth potential which does not provide enough social trust towards the consolidation efforts of the government. Journal of Economic Literature (JEL) classification: E61, E62, Q01


1977 ◽  
Vol 23 (1) ◽  
pp. 269-284 ◽  
Author(s):  
I.G. Burleigh

Nuclei have been enumerated in muscle fibres of different physiological properties within adult rats and rabbits. Almost invariably, and regardless of muscle type, there is a direct relationship between the cross-sectional area (or fibre breadth) of muscle fibres and the number of nuclei within them. The one exception occurred in muscles of older rats where increased nuclear numbers do not always appear to result in broader muscle fibres. The greater complement of nuclei in broader fibres is accompanied by larger amounts of cell substance per nucleus. Confirming early observations in the literature, red fibres of the slow-phasic type have more nuclei than have white, fast-phasic fibres of similar breadth. These conclusions are not vitiated by differences in the number of nuclei within capillaries or in satellite cells, by differences in nuclear length or by variation in the degree to which fibres are contracted. In respect of their complement of nuclei, and the average amount of cell substance formed per nucleus the small red fibres that occur within muscles of predominantly fast-phasic character appear to be fast-rather than slow-phasic in type. When the number of nuclei observed per fibre is plotted against fibre cross-sectional area, the shapes of the resulting distributions suggest that estimates of muscle nuclei may be valuable not only as an index of growth potential, but of the extent to which that potential is expressed. In one muscle, the above distribution was of a form which indicated that some fibres may have formed abnormally large amounts of protein per nucleus. However, this was not adequately confirmed. Various factors have been investigated that are relevant to the accuracy of enumerating nuclei and measuring fibre breadths.


Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5863
Author(s):  
Massimo Cardone ◽  
Bonaventura Gargiulo

This paper presents a virtual model of a scroll compressor developed on the one-dimensional analysis software Simcenter Amesim®. The model is semi-empirical: it needs some physical details of the modelled machine (e.g., the cubic capacity), but, on the other hand, it does not require the geometrical features of the spirals, so it needs experimental data to calibrate it. The model also requires rotational speed and the outlet temperature as boundary conditions. The model predicts the power consumption and the mass flow rate and considers leakages and mechanical losses. After the model presentation, this paper describes the test bench and the obtained data used to calibrate and validate the model. At last, the calibration process is described, and the results are discussed. The calculated values fit the experimental data also in extrapolation, despite the model is simple and performs calculations within 7 s. Due to these characteristics, the model is suitable for being used in a larger model as a sub-component.


1978 ◽  
Vol 5 (1) ◽  
pp. 61 ◽  
Author(s):  
PM Bremner ◽  
HM Rawson

The work reported here was done to explore the extent to which the mature weight of a grain is determined by (i) its potential for growth, defined as its intrinsic capacity to accumulate dry matter, and (ii) the resistance to assimilate transport imposed by the vascular system of the ear. Estimation of growth potential was attempted by observing the effects of systematic patterns of grain removal on the mature weights of grains remaining, these being compared with weights of matched grains from intact ears. Resistance to transport of assimilate was inferred from the apparent order of priority between grains for the supply of assimilate, as revealed by comparing their weights when assimilate supply was either normal, or reduced by plant shading. When neighbouring grains were removed, those remaining usually grew larger to an extent that indicated growth potential appreciably in excess of that utilized in intact ears under the most favourable conditions. Although grains within a spikelet of an intact ear attain quite different weights, the experiments suggested that their differing potentials for growth seemed to play only a minor role in this, and that the major influence was the relative ease with which assimilate could reach the grains; this depended largely on the distance of the grains from the spike rachis. Comparing between spikelets, the difference found in intact ears between grains in the same spikelet location tended to persist when some grains were removed from each spikelet, indicating a possible role of growth potential as a controlling influence. This may be partly due to the sequence of morphogenesis, established as early as the double ridge stage. Although the removal of competing grains within a spikelet usually enhanced the growth of the one remaining, this was not always so; there was evidence from one experiment that removal of competing grains towards the spikelet apex represented the removal of some beneficial influence. The bearing of the results on possible limitations to grain yield are discussed.


2013 ◽  
Vol 591 ◽  
pp. 329-333
Author(s):  
Liang Jiang ◽  
Yi Wang Bao ◽  
Xiao Gen Liu

Vacuum insulation panel is the one type of the insulation materials. The characteristics of this material are not only low thermal conductivity, good sound insulation, energy efficient, environmental protection but also with no ODS material. However, the inadequate mechanical properties of this material limit its application of insulation in construction . Thus, this research proposed the uses of the connection of structure and function of vacuum insulation panel in construction , and tested against its Sound Insulation Property. new construction sound insulation standards was adopted for evaluating the result of Sound Insulation Property to study the building insulation performance of the vacuum insulation composites


Author(s):  
Ehsan Basafa ◽  
Ryan J. Murphy ◽  
Michael D. Kutzer ◽  
Yoshito Otake ◽  
Mehran Armand

We report the results of planning and experimental validation of femoroplasty — augmentation of mechanical properties of the bone using polymethylmethacrylate (PMMA) bone cement injection — on osteoporotic femurs. For six pairs of osteoporotic femurs, finite element (FE) models were created using computed tomography (CT) scan data and an evolutionary method was used to optimize the cement pattern in one of the models from each pair. Using a particle method and the CT data, cement diffusion was modeled for several hypothetical augmentations and the one most closely matching the optimized pattern was chosen as the best plan. We used intra-operative navigation and a custom-designed injection device to deliver the cement into the bones precisely according to the plan. All femurs were then tested mechanically in a configuration simulating a fall to the side. Augmentation with this technique resulted in an increase in the yield load (28%) and yield energy (142%) compared to the control specimens, while only 9.8ml of cement was injected on average. Results support our hypothesis that significant improvements in the mechanical properties of osteoporotic femurs can be achieved by using minimal, and hence safe, amounts of PMMA bone cement.


Author(s):  
Alicia Dávila-Gutiérrez ◽  
Xóchitl López-Cano ◽  
Mariana López-Victoriano ◽  
Isabel Monroy-Plata

The Follow-up to the application of the Program of Studies of the Master in Educational Intervention for Basic Education (MIEEB), in the Normal School of Ixtlahuaca (ENI) is being made from various procedures, moments and functions, such as: the procedure “monitoring and evaluation to the application of plans and programs of postgraduate study” of the Quality Management System (QMS), another is the follow-up that is carried out from the position of the Postgraduate Coordinator. The objective of these procedures is: “Obtain information on the progress and incidences of Postgraduate Educational Programs that are offered in the Normal Schools, to help in the assurance of their educational quality "(SEN, 2017), and the one in this report, is to reflect on the results of the application of the MIEEB Program of Studies: strengths and weaknesses. The methodology of this study is based on the analysis of documents that have been administered to students and teachers, those that have been issued to inform school and educational authorities. It is intended to contribute to the reflection of the scope of the master’s program in the professionalization of teachers of Basic Education.


2018 ◽  
pp. 125-134
Author(s):  
Елена ПЕРЕПЁЛКИНА ◽  
Elena PEREPELKINA ◽  
Вячеслав ПЕРЕПЁЛКИН ◽  
Vyacheslav PEREPELKIN

The article examines conceptually and empirically tertiarisation as structural and economic characteristics of the transformation of modern society into a post-industrial. The authors substantiate the need for consistent fullfledged passage of the national socio-economic system of stages of civilizational development, based on which the author's definition of tertiaryization is given. A comparative cross-country quantitative analysis of the service sector in national economies makes it possible of strengthening the structural shift in favor of this sector in the economies of a group of countries with an average income level. High income level of the population is but one of the conditions for the existence of a developed service sector, as is confirmed by the example of a number of oil exporting countries. Along with poverty, the reason for the slow expansion of the service sector in the underdeveloped countries is their insufficient technological development. Russia lagged behind the global average level in the share of tertiary sector as well as in the rates of its growth. On the one hand, this is an evidence of the growth potential of the whole economy created by tertiarization, while, on the other hand, it speaks for a necessity of ensuring a higher quality of this growth. Problems of service sector’s growth structure are becoming more relevant in the current circumstances. An increase in the quality together with the one in the rates of growth might be attained on the basis of an outpacing expansion of the share of services and progressive dynamics of labor productivity in the process of services creation. At the same time, this requires a large stock of human capital in the country, which substantiates a conclusion about presence of tertiarization in its true sense only in economically developed countries. A negative attitude towards tertiarization in less developed countries may be explained by the dominance of traditional services in the tertiary sector of their economies that have greatly lost a capacity for accelerating the overall economic growth by now. Consequently, countries, in which an extended reproduction of human capital is implemented according to the needs for modernization of the industrial apparatus in the economy, benefit from tertiarization in the first place.


Solar Energy ◽  
2019 ◽  
Vol 193 ◽  
pp. 885-905 ◽  
Author(s):  
Takao Katsura ◽  
Ali Radwan ◽  
Zhang Yang ◽  
Makoto Nakamura ◽  
Katsunori Nagano

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