Thermodynamic Modelling of an Adsorption Chiller Based on a Zeolite

2015 ◽  
Author(s):  
Marco Badami ◽  
Armando Portoraro ◽  
Marco Simonetti ◽  
Paolo Tebaldi
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Numerical Model ◽  
Low Temperature ◽  
Low Power ◽  
Thermal System ◽  
Adsorption Chiller ◽  
Solar Cooling ◽  
Simulation Results ◽  
Solar Thermal System

Low power adsorption chillers with low desorption temperatures deserve particular attention, because of the possibility of driving them with a solar thermal system integrated with buildings. The monitoring of a recent solar cooling installation in Turin, Italy, has pointed out the opportunity of developing a dynamic mathematical model, in order to simulate the transient performances of this plant. Focusing on the aforementioned low power-low temperature adsorption chiller category, this work proposes a numerical model of the systems, that include a novel zeolite as the adsorbent and water as the refrigerant fluid. The simulation results have been verified by means of the nominal values of one of the very few commercial chillers of this typology available on the market, and have compared with experimental data found in the literature for similar plants.

scholarly journals Investigation of the Thickness Differential on the Formability of Aluminum Tailor Welded Blanks

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 875
Author(s):  
Jie Wu ◽  
Yuri Hovanski ◽  
Michael Miles
Keyword(s):  
Experimental Data ◽  
Finite Element ◽  
Numerical Model ◽  
Plastic Strain ◽  
Finite Element Model ◽  
Equivalent Plastic Strain ◽  
Element Model ◽  
Dome Height ◽  
Tailor Welded Blanks ◽  
Simulation Results

A finite element model is proposed to investigate the effect of thickness differential on Limiting Dome Height (LDH) testing of aluminum tailor-welded blanks. The numerical model is validated via comparison of the equivalent plastic strain and displacement distribution between the simulation results and the experimental data. The normalized equivalent plastic strain and normalized LDH values are proposed as a means of quantifying the influence of thickness differential for a variety of different ratios. Increasing thickness differential was found to decrease the normalized equivalent plastic strain and normalized LDH values, this providing an evaluation of blank formability.

Prevention of Corrosion in Austenitic Stainless Steel through a Predictive Numerical Model Simulating Grain Boundary Chromium Depletion

2017 ◽  
pp. 374-389
Author(s):  
M.K. Samal
Keyword(s):  
Mathematical Model ◽  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Numerical Model ◽  
Low Temperature ◽  
Grain Boundary ◽  
Stainless Steels ◽  
Predictive Models ◽  
Chromium Depletion ◽  
Sensitization Behavior

In this chapter, a mathematical model for rate of formation of chromium carbides near the grain boundary, which is a pre-cursor to chromium depletion and corresponding sensitization behavior in stainless steels, is presented. This model along with the diffusion equation for chromium in the grain has been used to obtain chromium depletion profiles at various time and temperature conditions. Finite difference method has been used to solve the above equations in the spherical co-ordinate system and the results of time-temperature-sensitization diagrams of four different types of alloys have been compared with those of experiment from literature. For the problem of low temperature sensitization and corresponding inter-granular corrosion in austenitic stainless steel, it is very difficult to carry out experiment at higher temperatures and justify its validity at lower operating temperatures by extrapolation. The development of predictive models is highly useful in order to design the structures for prevention of corrosion of the material in aggressive environments.

A numerical algorithm for constructing an individual mathematical model of HIV dynamics at cellular level

2018 ◽  
Vol 26 (6) ◽  
pp. 859-873 ◽  
Author(s):  
H. Thomas Banks ◽  
Sergey I. Kabanikhin ◽  
Olga I. Krivorotko ◽  
Darya V. Yermolenko
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Inverse Problem ◽  
Cellular Level ◽  
Free Virus ◽  
Hiv Dynamics ◽  
Infection Parameters ◽  
Simulation Results ◽  
The Mathematical Model ◽  
Fixed Times

Abstract In this paper a problem of specifying HIV-infection parameters and immune response using additional measurements of the concentrations of the T-lymphocytes, the free virus and the immune effectors at fixed times for a mathematical model of HIV dynamics is investigated numerically. The problem of the parameter specifying of the mathematical model (an inverse problem) is reduced to a problem of minimizing an objective function describing the deviation of the simulation results from the experimental data. A genetic algorithm for solving the least squares function minimization problem is implemented and investigated. The results of a numerical solution of the inverse problem are analyzed.

scholarly journals Internal Stability Evaluation of Soils

Water ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 1439
Author(s):  
Qingfeng Feng ◽  
Hao-Che Ho ◽  
Teng Man ◽  
Jiaming Wen ◽  
Yuxin Jie ◽  
...  
Keyword(s):  
Experimental Data ◽  
Grain Size ◽  
Numerical Model ◽  
Internal Stability ◽  
Combined Effects ◽  
Stability Evaluation ◽  
Major Threat ◽  
Satisfactory Performance ◽  
Proposed Model ◽  
Simulation Results

Suffusion constitutes a major threat to the foundation of a dam, and the likelihood of suffusion is always determined by the internal stability of soils. It has been verified that internal stability is closely related to the grain size distribution (GSD) of soils. In this study, a numerical model is developed to simulate the suffusion process. The model takes the combined effects of GSD and porosity (n) into account, as well as Wilcock and Crowe’s theory, which is also adopted to quantify the inception and transport of soils. This proposed model is validated with the experimental data and shows satisfactory performance in simulating the process of suffusion. By analyzing the simulation results of the model, the mechanism is disclosed on how soils with specific GSD behaving internally unstable. Moreover, the internal stability of soils can be evaluated through the model. Results show that it is able to distinguish the internal stability of 30 runs out of 36, indicating a 83.33% of accuracy, which is higher than the traditional GSD-based approaches.

scholarly journals Solar Community Energy and Storage Systems for Cold Climates

2021 ◽  
Author(s):  
Farzin Masoumi Rad
Keyword(s):  
Energy Storage ◽  
Heat Pump ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Solar Thermal ◽  
Base Case ◽  
Thermal System ◽  
Heating And Cooling ◽  
Simulation Results ◽  
Solar Thermal System

For a hypothetical solar community located in Toronto, Ontario, the viability of two separate combined heating and cooling systems were investigated. Four TRNSYS integrated models were developed for different cases. First, an existing heating only solar community was modeled and compared with published performance data as the base case with suggested improvements. The base case community was then used to develop a hypothetical solar community, located in Toronto, requiring both heating and cooling. In this second model an absorption chiller was added – Solar Thermal Chiller (STC) system. The chiller received its source heat from the solar thermal system with the supplemental heat from a natural gas boiler. The STC system was designed with two borehole thermal energy storage units (BTES). One was high-temperature BTES for the solar thermal energy storage, and another was medium-temperature BTES for the chillers’ heat rejection. The twenty year simulation results showed that by the fifth year in the heating season, the community operated with 100% solar fraction (SF). In the cooling season, the chiller received 18% of its required energy from the same number of solar collectors as the heating-only community system. The third model was based on the central heat pump system with borehole thermal storage for the heating and cooling, using a PV system as the heat pump power source - Heat Pump Photovoltaics (HPPV) system. The simulation results showed that the system operated favorably from the first year and did not have any significant performance degradation in 20 years. On average, the heat pumps performed with the seasonal COP of 3.3 in the heating mode and 5.9 in the cooling mode. The fourth system, Solar Thermal-Heat Pump Photovoltaics (ST-HPPV), a solar thermal system with borehole thermal energy storage as a supplemental heat source to the HPPV, was investigated. The simulation results showed that this system would be beneficial for a community with the annual heating and cooling difference of more than 75%. By adding a solar thermal system to the HPPV system, the heat pumps’ performance improved by 26% in the heating mode, and exhibited a negligible drop in the cooling mode.

scholarly journals FINDING THE LINEAR DEPENDENCE OF THE CROSS-SECTION PROFILE FOR A UNIFORM FEEDING OF BREAD MATERIAL IN THE THRESHING PROCESS

2020 ◽  
Author(s):  
I.R. Antypas ◽  
◽  
T.P. Savostina
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Numerical Model ◽  
Cross Section ◽  
Reliability Optimization ◽  
Profile Line ◽  
Section Profile ◽  
The Cross ◽  
Cross Section Profile ◽  
The Mathematical Model

The use of advanced methods and technologies of threshing and separation allows you to predict and minimize losses. The results of reliability optimization of the cross-section profile of the transporting device and its influence on threshing and separation have not yet been studied. To solve this problem, the article modeled a mathematical numerical model that allows you to describe the function of the cut profile line in a General way. The mathematical model is solved using experimental data.

Modeling and Simulation of a Co-current Rotary Dryer

2016 ◽  
Vol 12 (2) ◽  
pp. 189-194 ◽  
Author(s):  
Zhi-gang Huang ◽  
Yun-xuan Weng ◽  
Nan Fu ◽  
Zong-qiang Fu ◽  
Dong Li ◽  
...  
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Moisture Content ◽  
Mathematical Models ◽  
Modeling And Simulation ◽  
Air Temperature ◽  
Good Accuracy ◽  
Rotary Dryer ◽  
Simulation Results ◽  
The Mathematical Model

Abstract Mathematical models including mass and energy conservation were developed in order to predict the outlet particles temperature and moisture. As the inlet air temperature increased, the outlet particles temperature increased as well and the outlet particles moisture decreased quickly. The outlet particles temperature and moisture changed a little as a function of the speed of rotation at the low inlet air temperature, while the outlet particles temperature and moisture increased very apparently with the speed of rotation increased at the high inlet air temperature. The error of the simulation results compared to the experimental data showed good accuracy for particles temperature and moisture content. The mathematical model performs well to predict the outlet particles temperature and moisture content.

Numerical Model of the Temperature Control Curve Linearity of HVAC Module in Automobile Air-Conditioning System and Applications

2010 ◽  
Vol 2 (4) ◽  
Author(s):  
Xiaohua Qu ◽  
Zhaogang Qi ◽  
Junye Shi ◽  
Jiangping Chen ◽  
Hua Zhou
Keyword(s):  
Experimental Data ◽  
Numerical Model ◽  
Temperature Control ◽  
Air Conditioning ◽  
Airflow Rate ◽  
Air Conditioning System ◽  
Control Curve ◽  
Automobile Air Conditioning System ◽  
Simulation Results ◽  
Automobile Air Conditioning

In the present work, a numerical model of the temperature control curve (TCC) linearity of the heating ventilating and air conditioning (HVAC) module in automobile air-conditioning system is established. The numerical model is composed of several higher precision submodels. The simulation results are validated by experimental data performed on a calorimeter test bench. It is found that the simulation data agree with the experimental data very well. The maximum deviations of the airflow rate and the temperature are 3% and 1.4°C, respectively. The factors, which influenced the TCC linearity, are numerically studied. The simulation results show that the different door configuration needs to be matched with the division type for vent ducts of the HVAC module outlet, which can decrease the temperature stratification of airflow at the outlets. Cold and hot air mixing ratio determines the slope of the linearity curve. In addition, the further the distance between the HVAC module outlet and the mixing chamber and the greater the turbulent intensity, the more the cold-hot airflow will fully mix. It contributes to the temperature uniformity at the outlets.

Investigation of Hydroforming Technology for Manufacturing an Auto Complex Part

2019 ◽  
Vol 957 ◽  
pp. 138-147
Author(s):  
Viorel Paunoiu ◽  
Florian Pereira ◽  
Virgil Gabriel Teodor ◽  
Catalina Maier
Keyword(s):  
Experimental Data ◽  
Numerical Model ◽  
Rubber Membrane ◽  
Sheet Hydroforming ◽  
Part Geometry ◽  
Complex Part ◽  
Experimental Tool ◽  
Hydroforming Process ◽  
Simulation Results ◽  
Auto Part

Hydroforming process is used for obtaining different kinds of sheet metal components in an economic manner in terms of time and costs reduction and increase of the product quality. This paper deals with the application of this type of technology for manufacturing a rotational auto part from aluminium alloy. An experimental tool for hydroforming with rubber membrane was used. A set of dies with different geometries has been designed and constructed. Experiments have been conducted for investigation the ability of transferring features from the die onto the blank surface for different die geometries and pressures. The hydroformed part was measured using CMM. Based on the experimental data a numerical model was designed. FEM using Abaqus solver was used for investigated the part geometry and the effective stress distribution under various pressures conditions and dies geometries. The experimental and simulation results show the feasibility of applying the sheet hydroforming process in order to obtain a sound product.

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