Experimental Investigation of The Optimal Location of PCM Capsules in a Hollow Brick Wall

2021 ◽  
Vol 39 (5A) ◽  
pp. 846-858
Author(s):  
Hayder M. Abbas ◽  
Jalal M. Jalil ◽  
Sabah T. Ahmed
Keyword(s):  
Experimental Investigation ◽  
Time Lag ◽  
Optimal Location ◽  
Test Model ◽  
Insulation Material ◽  
Brick Wall ◽  
Optimum Location ◽  
Test Room ◽  
Inner Surface ◽  
Hollow Brick

In this paper, an experimental investigation of the integration of PCM capsules as insulation material into the outer or inner rows of hollow brick to find out the optimum location of the PCM capsules that give the best thermal performance of a wall. A test model consists of two identical cubical rooms was designed and fabricated to test the wall with and without PCM in a natural outdoor condition in Diwaniyah city in Iraq during the summer. The results show that the PCM will reduce the temperature of the inner side of the test wall and test room by 2.7℃ for the PCM capsules in the inner row while the reduction in both the inner surface temperature and the room due to the use of the capsules in the outer row was 1.9℃. The time lag for the two cases was 1 hour. So that, the inner row location of PCM is the optimum location.  

Information technology investment and innovation performance: does investment paradox exist?

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Peinan Ji ◽  
Xiangbin Yan ◽  
Yan Shi
Keyword(s):  
Information Technology ◽  
Time Lag ◽  
Innovation Performance ◽  
Test Model ◽  
It Investment ◽  
Firm Innovation ◽  
Data Set ◽  
Content Type ◽  
Lag Effect ◽  
Enterprise Innovation

Purpose The purpose of this study is to deepen the understanding of the effects of information technology (IT) investment on firm innovation performance and examining the investment paradox effect in China. Design/methodology/approach Using a sample of China’ public firms IT investment data between 2010 and 2016, the authors establish a test model of IT investment and innovation performance. Findings The result indicates that IT investment in firms have no effect on innovation performance in the investment period. However, in the full sample and manufacturing sample, the IT investment has a significant positive effect on innovation performance in the post-investment years. In addition, this study finds that large companies and low-age companies may contribute more to innovation when firm investment in IT. Research limitations/implications There are several limitations in this research. First, the authors are failed to obtain a larger sample about the IT investment information data set in China, so this study was compelled to use limited sample data from China, hence, this could lead to errors of too early generalization. Second, the authors use the number of invention patent applications to represent the performance of enterprise innovation, which may not show enterprise innovation effectively. Third, the firms in the sample are all in China Listed Companies, so this may not accurately reflect the entire environment of firm innovation performance, and could possibly. Practical implications The research confirms that there is a paradox and time lag effect in IT investment, which enterprises should pay attention to. Originality/value Existing research confirms that corporate IT investments can bring new products or services. However, the authors still do not know whether IT investment has improved the company’s ability of innovation. This study will fill this gap and the industry effect and time lag effect of the influence of IT investment on innovative performance are also examined.

scholarly journals Experimental investigation of rockwool insulation hygrothermal properties related to material structure

2015 ◽  
Vol 19 (3) ◽  
pp. 923-928 ◽  
Author(s):  
Maja Djurovic-Petrovic
Keyword(s):  
Thermal Conductivity ◽  
Experimental Investigation ◽  
Sorption Properties ◽  
Material Structure ◽  
Insulation Material ◽  
Wide Range ◽  
Two Samples

The hygrothermal properties related to rockwool insulation material structure with different additives are presented using rockwool insulation products obtained from row material of southern Serbia (Vranje region) in the wide range of reference temperatures (10?C to 70?C). The hygrothermal properties of basic sample (without additives) are compared to two samples with different additives for two sets of rockwool insulation samples namely: light-soft-panels (LSP) with density of 50 kg/m3, and middle-weight-panels (MWP) with density of 80 kg/m3. It is shown that there is significant (approximately 10%) improvement of thermal conductivity for additives based on zeolite. Also, correlation of thermal conductivity and sorption properties of selected samples are presented.

An Investigation of Cavitation and Suction Vortices Behavior in Pump Sump

2011 ◽  
Author(s):  
Won-Tae Kang ◽  
Ki Han Yu ◽  
Seung Yeob Lee ◽  
Byeong Rog Shin
Keyword(s):  
Experimental Investigation ◽  
Numerical Analysis ◽  
Test Procedure ◽  
Three Dimensional ◽  
Water Levels ◽  
National Standard ◽  
Piping System ◽  
Test Model ◽  
Grid Systems ◽  
Volume Method

A numerical and an experimental investigation on a suction vortices including cavitation, free vortices and subsurface vortices behavior in the model sump system with multi-intakes is performed at several flow rates and water levels. A test model sump and piping system were designed based on Froude similitude for the prototype of the recommended structure layout by HI-9.8 American National Standard for Pump Intake Design of the Hydraulic Institute. An experiment is performed according to the sump model test procedure of Hyosung Goodsprings, Inc. A numerical analysis of three dimensional multiphase flows through the model sump is performed by using the finite volume method of the CFX code with multi-block structured grid systems. A k-ω Shear Stress Transport turbulence model and the Rayleigh-Plesset cavitation model are used for solving turbulence cavitating flow. Several types of free surface and submerged vortex which occurs with each different water level are identified through the experimental investigation. From the numerical analysis, the vortices are reproduced and their formation, growing, shedding and detailed vortex structures are investigated. To reduce abnormal vortices, an anti-vortex device is considered and its effect is investigated and discussed.

Experimental investigation on the influencing factors of preparing porous fly ash-based geopolymer for insulation material

2018 ◽  
Vol 168 ◽  
pp. 9-18 ◽  
Author(s):  
Yajun Huang ◽  
Lunlun Gong ◽  
Long Shi ◽  
Wei Cao ◽  
Yuelei Pan ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
Fly Ash ◽  
Influencing Factors ◽  
Insulation Material

Microclimate Variations with Wall Configurations for Chinese Solar Greenhouses

2013 ◽  
Vol 291-294 ◽  
pp. 931-937 ◽  
Author(s):  
Hui Xu ◽  
Lan Jie Zhao ◽  
Guo Hong Tong ◽  
Yi Qing Cui ◽  
Tian Lai Li
Keyword(s):  
Thermal Stability ◽  
Fly Ash ◽  
Cooling Rate ◽  
Heating Rate ◽  
Small Hole ◽  
Brick Wall ◽  
Optimal Temperature ◽  
Clay Brick ◽  
The North ◽  
Hollow Brick

Five greenhouses with different typical wall configurations were studied, including the hollow brick wall (HB), clay brick wall composed of mural column (MCCB), wall composed of fly ash air block brick (FAABB), clay brick wall composed of plum small hole column (PSHCCB), common clay brick wall with Styrofoam wall outside (SCB) to find out the effects of the north walls on the greenhouse microclimate. The interior temperature and RH environment, as well as the heating rate, cooling rate and the correlation with the outside temperature, were tested and compared, finding that the greenhouse with FAABB exhibits the optimal temperature and RH environment, and also the highest thermal stability. The findings may provide references for greenhouse construction and insulation measures.

Studies on Effects of Periodic Wake Passing Upon a Blade Leading Edge Separation Bubble: Experimental Investigation Using a Simple Leading Edge Model

2003 ◽  
Author(s):  
K. Funazaki ◽  
K. Yamada ◽  
Y. Kato
Keyword(s):  
Experimental Investigation ◽  
Separation Bubble ◽  
Leading Edge ◽  
Test Cases ◽  
Test Model ◽  
Flat Plates ◽  
Aerodynamic Interaction ◽  
Edge Separation ◽  
Wake Passing ◽  
Probe Measurements

This paper describes experimental investigation on aerodynamic interaction between incoming periodic wakes and leading edge separation bubble on a compressor or turbine blade, using a scaled leading edge model. The studies aims at expanding the range of the test conditions from that of the previous study (Funazaki and Kato [15]) in order to deepen the knowledge on how and to what extent upstream wake passing suppresses the leading edge separation bubble. Special attention is paid to the transitional behaviors of the separated boundary layers, in particular, to the emergence of wake-induced turbulence spots. Hot-wire probe measurements are then executed under five different flow conditions. The test model has a simple structure consisting of a semi-circular leading edge and two flat-plates. Cylindrical bars of the wake generator generate the periodic wakes in front of the test model. Effects of Reynolds number, Strouhal number, direction of the bar movement and incidence of the test model against the incoming flow are examined in this paper. The measurements reveal that the wake moving over the separation bubble does not directly suppress the separation bubble. Instead, wake-induced turbulence spots and the subsequent calmed regions have dominant impacts on the separation bubble suppression for the all test cases. Distinct difference of the bubble suppressing effect by the wakes is also observed when the direction of the bar movement is altered.

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