Integrated Systems for Cogeneration and Absorption Chilling: Comparison for Varying Chiller COPs

1999 ◽  
Author(s):  
R. Tang ◽  
M. A. Rosen
Keyword(s):  
Steam Turbine ◽  
Integrated System ◽  
Coefficient Of Performance ◽  
Integrated Systems ◽  
Base Case ◽  
Cooling Load ◽  
Absorption Chillers ◽  
Multi Stage ◽  
Wide Range ◽  
Thermodynamic Effects

Abstract The thermodynamic effects are demonstrated of integrating steam turbine-based cogeneration systems with absorption chillers. A wide range of realistic extraction steam pressures and coefficient of performance (COP) values of absorption chillers are considered. A simple model of a steam turbine-based cogeneration plant is used for the evaluation of the integrated system. The integrated systems are evaluated based on the ratio of fuel consumption between a base case (one-stage absorption chiller with a COP value of 0.6) and several alternative cases (multi-stage absorption chillers with COP values ranging from 0.6 to 1.5). Two categories of scenarios are considered: (i) cases where the cooling load is fixed; and (ii) cases where the cooling load is fixed and the electrical output for the integrated system is set equal to that for the base case.

Memperkuat Daya Saing Bank Syariah Dengan Meningkatkan Kemampuan Teknologi Informasi

Liquidity ◽  
2018 ◽  
Vol 1 (1) ◽  
pp. 32-41
Author(s):  
Amrizal Amrizal
Keyword(s):  
Information System ◽  
Credit Card ◽  
Banking Industry ◽  
Integrated System ◽  
Integrated Systems ◽  
Islamic Banks ◽  
Electronic Money ◽  
Electronic Transactions ◽  
Excellent Service ◽  
Debit Cards

Banking industry is very tight competition in all aspects. Results review from some literatures: journals and empirical data indicates that the banking industry has been applied information technology in order to provide excellent service to customers in the form of electronic transactions such as ATM, sms banking, e-commerce and so forth. Based on Bank Indonesia reports, the type of electronic transaction has been growing very rapidly between the transaction and Bilyetgiro Elekteronik Checks, ATM, Credit Card, Account Card Based (ATM and Debit Cards), Electronic Money, Delivery Chanel and RTGS. Those above transactions are relating to the Technology Information System and Integrated System. Integrated system is the combination of Hardskill which focus on knowledge and more to the integrity softskill (shidiq, trustworthy, tablig, fathonah). Islamic banks are ready to face competition both nationally and internationally, primarily face competition from the aspect of Integrated Systems. Bank Syariah Mandiri (BSM) developed e-banking features on an ongoing basis, among others

scholarly journals Research on Double-Stage and Multi-Stage Capacitive Deionization Absorption Air-Conditioning System

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 395
Author(s):  
Feng Cheng ◽  
Boqing Ding ◽  
Xiuwei Li
Keyword(s):  
Air Conditioning ◽  
Pure Water ◽  
Good Choice ◽  
Coefficient Of Performance ◽  
Capacitive Deionization ◽  
Joint Work ◽  
Thermal Regeneration ◽  
Air Conditioning System ◽  
Multi Stage ◽  
Stage System

An absorption air-conditioning system is a good choice for green buildings. It has the superiority in the utilization of renewable energy and the refrigerant is environment-friendly. However, the performance of the traditional absorption system has been restricted by the energy waste in the thermal regeneration process. Capacitive deionization (CDI) regeneration is proposed as a potential method to improve system efficiency. In the new method-based air-conditioning system, strong absorbent solutions and pure water are acquired with the joint work of two CDI units. Nevertheless, the practical CDI device is composed of a lot of CDI units, which is quite different from the theoretical model. To reveal the performance of multiple CDI units, the model of the double/multi-stage CDI system has been developed. Analysis has been made to expose the influence of some key parameters. The results show the double-stage system has better performance than the single-stage system under certain conditions. The coefficient of performance (COP) could exceed 4.5, which is higher than the traditional thermal energy-driven system, or even as competitive as the vapor compression system. More stages with proper voltage distribution better the performance. It also provides the optimization method for the multi-stage CDI system.

scholarly journals The effectiveness of weed regulation methods in spring wheat cultivated in integrated, conventional and organic crop production systems

2012 ◽  
Vol 52 (4) ◽  
pp. 486-493 ◽  
Author(s):  
Beata Feledyn-Szewczyk
Keyword(s):  
Spring Wheat ◽  
Crop Production ◽  
Dry Matter ◽  
Production Systems ◽  
Integrated System ◽  
Integrated Systems ◽  
Conventional System ◽  
Weed Species ◽  
Organic System ◽  
Weed Communities

Abstract The research was conducted from 2008 to 2010, and compared the influence of different weed control methods used in spring wheat on the structure of the weed communities and the crop yield. The study was carried out at the Experimental Station of the Institute of Soil Science and Plant Cultivation - State Research Institute in Osiny as part of a long-term trial where these crop production systems had been compared since 1994. In the conventional and integrated systems, spring wheat was grown in a pure stand, whereas in the organic system, the wheat was grown with undersown clover and grasses. In the conventional system, herbicides were applied two times in a growing season, but in the integrated system - only once. The effectiveness of weed management was lower in the organic system than in other systems, but the dry matter of weeds did not exceed 60 g/m2. In the integrated system, the average dry matter of weeds in spring wheat was 4 times lower, and in the conventional system 10 times lower than in the organic system. Weed diversity was the largest in spring wheat cultivated in the organic system. In the conventional and integrated systems, compensation of some weed species was observed (Viola arvensis, Fallopia convolvulus, Equisetum arvense). The comparison of weed communities using Sorenson’s indices revealed more of a similarity between systems in terms of number of weed species than in the number of individuals. Such results imply that qualitative changes are slower than quantitative ones. The yield of grain was the biggest in the integrated system (5.5 t/ha of average). It was 35% higher than in the organic system, and 20% higher than in conventional ones.

Using CFD to Enhance the Preliminary Design of High-Pressure Steam Turbines

2013 ◽  
Author(s):  
Juri Bellucci ◽  
Federica Sazzini ◽  
Filippo Rubechini ◽  
Andrea Arnone ◽  
Lorenzo Arcangeli ◽  
...  
Keyword(s):  
High Pressure ◽  
Steam Turbine ◽  
Design Tool ◽  
Tip Clearance ◽  
Large Set ◽  
Preliminary Design ◽  
Steam Turbines ◽  
High Pressure Steam ◽  
Wide Range ◽  
Pressure Steam

This paper focuses on the use of the CFD for improving a steam turbine preliminary design tool. Three-dimensional RANS analyses were carried out in order to independently investigate the effects of profile, secondary flow and tip clearance losses, on the efficiency of two high-pressure steam turbine stages. The parametric study included geometrical features such as stagger angle, aspect ratio and radius ratio, and was conducted for a wide range of flow coefficients to cover the whole operating envelope. The results are reported in terms of stage performance curves, enthalpy loss coefficients and span-wise distribution of the blade-to-blade exit angles. A detailed discussion of these results is provided in order to highlight the different aerodynamic behavior of the two geometries. Once the analysis was concluded, the tuning of a preliminary steam turbine design tool was carried out, based on a correlative approach. Due to the lack of a large set of experimental data, the information obtained from the post-processing of the CFD computations were applied to update the current correlations, in order to improve the accuracy of the efficiency evaluation for both stages. Finally, the predictions of the tuned preliminary design tool were compared with the results of the CFD computations, in terms of stage efficiency, in a broad range of flow coefficients and in different real machine layouts.

Thermodynamic Performance of an Actual Thermo-Acoustic Refrigeration Micro-Cycle

2012 ◽  
Vol 614-615 ◽  
pp. 64-68
Author(s):  
Tuo Wang ◽  
Feng Wu ◽  
Jin Hua Fei ◽  
Ming Fang Liu
Keyword(s):  
Coefficient Of Performance ◽  
Pressure Amplitude ◽  
Cooling Load ◽  
Acoustic Effect ◽  
Thermodynamic Performance ◽  
Monotonically Increasing Function ◽  
Analytic Expressions ◽  
New Type ◽  
The Relationship ◽  
Increasing Function

Thermo-acoustic refrigerator is a new type of engine, which is based on the thermo-acoustic effect. A new model which expresses as an ellipse in pressure-volume diagram is established to investigate the thermodynamic performance of an actual thermo-acoustic refrigeration micro-cycle. The demarcation points of endothermic processes and exothermic processes in the actual micro-cycle are found. The analytic expressions of the dimensionless cooling load and the coefficient of performance (COP) are deduced. The relationship between the dimensionless cooling load and the COP are investigated by numerical examples. The results show that the dimensionless cooling load is a monotonically increasing function of the COP and the pressure amplitude.

Increase of energy efficiency ratio of a direct evaporative cooler by dynamic behavior with energy and exergy analysis

2021 ◽  
pp. 095440622110420
Author(s):  
Behzad Omidi Kashani
Keyword(s):  
Energy Efficiency ◽  
Electrical Energy ◽  
Coefficient Of Performance ◽  
Dynamic State ◽  
Circulation Rate ◽  
Cooling Load ◽  
Efficiency Ratio ◽  
Static State ◽  
Circulation Pump ◽  
Water Rate

The present research is about increasing the energy efficiency ratio (EER) in current direct evaporative coolers (DEC) in Iran. Increasing the cooling load and reducing the electrical energy consumption simultaneously (increasing the energy efficiency ratio (EER)) in DEC are the main goals of manufacturers and consumers of this device. When the circulation water pump runs continuously (static state), the circulation water rate is about 1.89 to 2.90 times of the amounts recommended in the reasonable standards. In order to adjust the circulation water rate to the recommended amount by standards, the present study has utilized repetitive cyclic scheduling programs to reduce the circulation rate to the optimal amount, (by turning the circulation pump on and off by dynamic pattern operation). In other words, the circulation pump stays on only for a certain period of a working cycle, and then the pump stays off for the rest of it. The cooling load and EER were measured based on ASHRAE 133 (2015). The results indicated that the cooling load in the dynamic state increased by 5.03 and 6.18 percent compared to the static state at low and high fan speeds, respectively. Moreover, in comparison with the static state, the amount of electrical energy consumed (kW-hr) in the dynamic state decreased by 8.8 and 4.2 percent at low and high fan speeds, respectively. Finally, the coefficient of performance (COP or EER) of the DEC in the dynamic state is increased by 15.16 and 10.78 in comparison with the static state at low and high fan speeds, respectively.

scholarly journals The Study of Internet Use and Academic Achievement of Elementary Students in Bangkok

2016 ◽  
Vol 6 (2) ◽  
pp. 71
Author(s):  
Aouyporn Suphasawat ◽  
Sirichai Hongsanguansri ◽  
Patcharin Seree ◽  
Ouaychai Rotjananirunkit
Keyword(s):  
Academic Achievement ◽  
Social Media ◽  
Math Achievement ◽  
Achievement Test ◽  
Internet Usage ◽  
School Students ◽  
Wide Range Achievement Test ◽  
Multi Stage ◽  
Wide Range ◽  
Negative Effect

<p>The purpose of this study is to investigate the relationship between internet usage behavior and academic achievement among elementary school students from grade 4-6 in Bangkok. The researcher employed Multi-stage Sampling to recruit 297 samples. The data was gathered via the following tests: 1) Intelligence tests, namely Colored Progressive Matrices (CPM) for students aged 5-11 year old or Standard Progressive Matrices (SPM) for 12 year old and above, and 2) Academic achievement test, namely Wide Range Achievement Test Thai Edition: WRAT-Thai. The findings revealed that time spent on the internet is negatively correlated to student’s reading achievement (r = -.24, p &lt; .001), spelling achievement (r = -.26, p &lt; .001), and math achievement (r = -.20, p = .001). More surprisingly, academic related internet usage was also found to be negatively correlated to math achievement (r = -.20, p &lt; 0.05). Meanwhile, internet usage for social media has a correlation with academic achievement in math and reading, (r = -.20, p = .001) and (r = -.13, p &lt; .05), respectively. Moreover, internet usage for entertainment was found to have a negative correlation with academic achievement in reading, spelling and math, (r = -.25, p &lt; .001), (r = -.27, p &lt; .001) and (r = -.21, p &lt; .001), respectively. Internet usage for online business, however, yielded no correlation to academic achievement. The study concluded that daily internet usage does have an effect on academic achievement in math. Moreover, when used for entertainment and social media, internet usage can pose a negative effect on academic achievement in reading and writing.</p>

Performance Prediction and Optimization of Low Pressure Steam Turbine Radial Diffuser at Design and Off-Design Conditions Using Streamline Curvature Method

2017 ◽  
Vol 139 (7) ◽  
Author(s):  
Luying Zhang ◽  
Francesco Congiu ◽  
Xiaopeng Gan ◽  
David Karunakara
Keyword(s):  
Steam Turbine ◽  
Flow Separation ◽  
Large Scale ◽  
Current Method ◽  
Low Pressure ◽  
Numerical Approach ◽  
Optimization Process ◽  
Exhaust Hood ◽  
Streamline Curvature ◽  
Wide Range

The performance of the radial diffuser of a low pressure (LP) steam turbine is important to the power output of the turbine. A reliable and robust prediction and optimization tool is desirable in industry for preliminary design and performance evaluation. This is particularly critical during the tendering phase of retrofit projects, which typically cover a wide range of original equipment manufacturer and other original equipment manufacturers designs. This work describes a fast and reliable numerical approach for the simulation of flow in the last stage and radial diffuser coupled with the exhaust hood. The numerical solver is based on a streamline curvature throughflow method and a geometry-modification treatment has been developed for off-design conditions, at which large-scale flow separation may occur in the diffuser domain causing convergence difficulty. To take into account the effect of tip leakage jet flow, a boundary layer solver is coupled with the throughflow calculation to predict flow separation on the diffuser lip. The performance of the downstream exhaust hood is modeled by a hood loss model (HLM) that accounts for various loss generations along the flow paths. Furthermore, the solver is implemented in an optimization process. Both the diffuser lip and hub profiles can be quickly optimized, together or separately, to improve the design in the early tender phase. 3D computational fluid dynamics (CFD) simulations are used to validate the solver and the optimization process. The results show that the current method predicts the diffuser/exhaust hood performance within good agreement with the CFD calculation and the optimized diffuser profile improves the diffuser recovery over the datum design. The tool provides General Electric the capability to rapidly optimize and customize retrofit diffusers for each customer considering different constraints.

Performance analysis of a multi-stage ultra-supercritical steam turbine using computational fluid dynamics

2015 ◽  
Vol 87 ◽  
pp. 352-361 ◽  
Author(s):  
Hyuck Jun Jang ◽  
Soo Young Kang ◽  
Jeong Jin Lee ◽  
Tong Seop Kim ◽  
Seong Jin Park
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Performance Analysis ◽  
Steam Turbine ◽  
Multi Stage

scholarly journals ENERGY IMPLEMENTATION OF SOLAR PANELS FOR REFRIGERATOR NEEDS LOAD FISHING RESULTS 80 WATT MAXIMUM CAPACITY 20 KG

2019 ◽  
Vol 4 (1) ◽  
pp. 19-31
Author(s):  
A. YUNUS NASUTION ◽  
ADITYA PRATAMA
Keyword(s):  
Power Consumption ◽  
Solar Panel ◽  
Coefficient Of Performance ◽  
Total Power ◽  
Cooling Load ◽  
Solar Panels ◽  
Average Output ◽  
Average Value ◽  
Battery Capacity ◽  
Compressor Power

The initial problems of fishermen still use their semi-modern catches and still use ice cubes as a cooling medium, due to the lack of innovation in the development of the cooling media caught by fishermen. The implementation of solar panel energy is the beginning for the development of refrigerator power consumption caught by fishermen. The goal is to calculate the cooling load on the refrigerator, calculate the Coefficient of performance (COP) at the refrigerator and the loading factors at the refrigerator, where the average ambient temperature is 34 ℃ and the temperature to be achieved is 0℃, the fisherman results used in the study this is a shrimp with a capacity of 20 kg and the cooling time is 4 hours. Where the total cooling load value is 244.29 Watt, multiplied by 10% safety factor, so the overall cooling load is 268.72 Watts, refrigerant mass flow rate is 0.0012 Kg / s, the evaporator capacity is 261 Watt, compressor power is 15.6 Watt, The coefficient of performance (COP) value was 16.73 while for the refrigerant capacity was 0.074 Tons of refrigerant, the loading factors in the study were used to run a refrigerator with 80 Watt power for 4 hours, so that the total refrigerator load was 320 Wh (Watt hour) , to produce 320 Wh power is used 2 solar panel modules with a capacity of 50 Wp (Watt Peak), and uses a solar change controller (SCC) with a capacity of 10 A. The output power of the solar panel is influenced by the intensity of the sun's light emitted, from the test obtained an average value the average output of solar panels is 90.6 watts, while the total power generated in 11 test points is 536 watts, the type used is polycrystalline, solar panels battery and inverter capacity must be greater than the refrigerator power consumption, in this study used a 12V 35 Ah battery capacity and 500 Watt Inverter

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