scholarly journals Comparative Analysis of Three Calculation Models to Simulate Energy Performance of Aerogel Glazing System

2020 ◽  
Author(s):  
Dongmei Zheng ◽  
Youming Chen ◽  
Yaling Xiao ◽  
Yang Liu ◽  
Yupeng Li ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Energy Performance ◽  
Calculation Models

scholarly journals The Impact of Infiltration on Heating Systems Dimensioning in Estonian Climate

2020 ◽  
Vol 172 ◽  
pp. 05004
Author(s):  
Raimo Simson ◽  
Taaniel Rebane ◽  
Martin Kiil ◽  
Martin Thalfeldt ◽  
Jarek Kurnitski
Keyword(s):  
Air Temperature ◽  
Indoor Air ◽  
Energy Performance ◽  
Simulation Software ◽  
Heat Losses ◽  
Climatic Data ◽  
Heating Systems ◽  
Air Temperatures ◽  
The Impact ◽  
Calculation Models

In this study we analysed the climatic conditions for infiltration estimation, different calculation methods and infiltration impact on heat load for heating systems dimensioning. To determine the wind conditions at low air temperatures of the coastal- and inland climatic zones in Estonia, 42 years of climatic data for Tallinn and Tartu were investigated. Calculation models with detailed air leakages were constructed of a single and two-storey detached house using dynamic simulation software IDA ICE. Simulations were carried out with the constructed calculation models, simulating various wind and sheltering conditions to determine the heating load of the buildings under measured wind conditions at the design external air temperatures. The simulation results were compared with results calculated with European Standard EN 12831:2017, methodology given in the Estonian regulation for calculating energy performance of buildings and with simulations using the default settings in IDA ICE based on the ASHRAE design day conditions. The percentage of heat losses caused by infiltration was found as 13-16% of all heat losses for the studied buildings. Simulations with historical climate periods showed that even in windy weather conditions the heating system dimensioned by the methods analysed may not be able to provide the required indoor air temperature. Analysis using the coldest and windiest periods showed that when systems are dimensioned by the studied methods, the highest decline in indoor air temperature occurs on the windiest day and not on the coldest day. The impact of high wind speeds and low sheltering conditions resulted up to 50% of all heat losses.

scholarly journals Optimization of the Lens Nucleus Fragmentation during Phacoemulsification in Patients with Pseudoexfoliation Syndrome

2018 ◽  
Vol 15 (3) ◽  
pp. 273-279
Author(s):  
V. M. Malov ◽  
A. V. Zolotarev ◽  
E. B. Eroshevskaya ◽  
I. V. Malov ◽  
A. E. Gorbunov
Keyword(s):  
Visual Acuity ◽  
Comparative Analysis ◽  
Surgical Treatment ◽  
Corneal Epithelium ◽  
Morphological Changes ◽  
Energy Performance ◽  
Pseudoexfoliation Syndrome ◽  
Radius Of Curvature ◽  
Equatorial Zone ◽  
Original Design

Objective:Comparative analysis of the results of phacoemulsification (FEC) with the use of developed and classic technologies for fragmentation of the lens nucleus in patients with pseudoexfoliation syndrome (PES).Patients and methods.The proposed technology is gentle crushing of the lens nucleus in patients with PES, you can reduce the pressure on the fibers of the zonule, the probability of damage to the ligaments and posterior capsule of the lens based on the use of phacofragmentation original design. To determine the radius of curvature of the working part of the tool a morphometrical measurement of the curvature of the equatorial zone of the lens cores removed during extracapsular and intracapsular cataract extraction in patients with PEX subluxation of the lens was carried out. A comparative analysis of the operation and the results of surgical treatment of cataract in patients with PEX with the use of the proposed (n = 58) and standard (n = 56) technologies of the nucleus fragmentation in phacoemulsification was made. The following ultrasound parameters were estimated: the average capacity in % (AVEUS), the average values of the absolute time ultrasound (APT) and average values of effective (EPT) time of ultrasound, in seconds, during phacoemulsification; structural-morphological changes in the posterior epithelium of the cornea according to the endothelial microscopy; the frequency and nature of complications, the visual acuity.Results.Morphometry of the lens nuclei in patients with pseudoexfoliation syndrome allowed to determine the average radius of curvature of the nucleus equator, which is made up 2.89 ± 0.14 mm, according to the performance curve of the Gauss — 2.895– 3.530 mm. These data are taken into account when selecting the radius of curvature of the working part of phacofragmentation (the radius of curvature of 3.0 mm) used with FEC in patients with PES (Patent RU152761 from 25.05.2015). The proposed chopper due to the conformity of the working part curvature of the tool and the Equatorial zone of cataract kernel can reliably capture and grind it, thus eliminating excessive pressure on the ligaments of the crystalline lens in patients with PES. Developed technology contributes to significantly reduction of the energy performance of ultrasound: AVEUS — 2.64–10.00 %; APT — 3.38–14.00 %; EPT — on 3.76– 16.00 % by 6.76 % in patients with different of the lens nucleus density degree, decrease operative and postoperative complications twice, 1.5 times less cell loss back the corneal epithelium. Visual acuity without correction from the first days after surgery was higher than 0.5 (average of 0.70 ± 0.05) in all the patients and increased to an average of 0.91 ± 0.01 within 12 months in patients of the main and 0.85 ± 0.02 — control groups.Conclusion.The developed technology of fragmentation of the lens nucleus reduces the time of phacoemulsification, reduces the ultrasound load, causes a smaller loss of cells at the back of the corneal epithelium, reduces the possible complications of the iris and ciliary body, which increases the efficiency of surgical treatment of cataract in patients with PEX.

Development of an Innovative Raw Milk Dispenser Based on Nanofluid Technology

2016 ◽  
Vol 12 (2) ◽  
pp. 165-172 ◽  
Author(s):  
Giovanni A. Longo ◽  
Giulia Righetti ◽  
Claudio Zilio
Keyword(s):  
Aqueous Solution ◽  
Comparative Analysis ◽  
Food Safety ◽  
Energy Saving ◽  
Raw Milk ◽  
Energy Performance ◽  
Point Of View ◽  
Traditional System ◽  
Temperature Range ◽  
Time Required

Abstract This paper presents the comparative analysis of a traditional raw milk dispenser and an innovative prototype based on nanofluid technology. The traditional raw milk dispenser consists of an off-the-shelf upright air-cooled refrigerator sold on the market, whereas the innovative prototype presents a tank equipped with a serpentine tube jacket operated with Al2O3–ethylene glycol aqueous solution nanofluid. The systems are experimentally analysed in the ambient temperature range of 19–35°C to evaluate the energy performance and the temperature control of the milk tank. The innovative prototype is demonstrated to be superior from the point of view of both energy saving and food safety. In fact, the innovative prototype exhibits a 63–70% energy saving with respect to the traditional one. Furthermore, the prototype distributor is able to reach the “safe” temperature of 4°C in about half of the time required by traditional system and it keeps the milk always in the “safe” temperature range 2–3°C, while the traditional distributor displays locally milk temperature higher than 4°C.

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