The Experts below are selected from a list of 276 Experts worldwide ranked by ideXlab platform
Guangming Chen - One of the best experts on this subject based on the ideXlab platform.
-
exergetic and economic analyses of a novel modified solar heat powered ejection compression refrigeration Cycle comparing with Conventional Cycle
Energy Conversion and Management, 2018Co-Authors: Yingjie Xu, Mengjie Song, Qin Wang, Ning Jiang, Guangming ChenAbstract:Abstract In this paper, a novel modified ejection-compression refrigeration Cycle is studied and compared with Conventional ejection-compression refrigeration Cycle based on exergetic and economic analyses. The novel Cycle is expected to improve the low practicability of Conventional ejection-compression Cycle with better thermal efficiency, smaller solar collector and more excellent economic performance. Energy performance is simply evaluated based on thermal efficiency and global coefficient of performance. The results show the novel Cycle is better in both the two indicators, which confirmed that it needs much less solar heat and smaller collector, and has better practicability. With the above data, exergy analysis is performed, showing the total exergy destruction of the novel Cycle is 23.97 kW less than a Conventional Cycle and exergy efficiency of the novel Cycle is always higher than the Conventional Cycle in the studied range. Economic analyses taking into consideration the impact of carbon dioxide emission are finished under base case. The results reveal the novel Cycle has a total cost rate 24.4% lower and a solar collector 89.5% smaller than those of a Conventional Cycle. The economic advantage of the novel Cycle will remain, even both electricity price and carbon dioxide penalty cost increase to 3.1 times of the current price. These improvements in energy and economy indicate the novel Cycle has an excellent application potential.
-
refrigerant evaluation and performance comparison for a novel hybrid solar assisted ejection compression refrigeration Cycle
Solar Energy, 2018Co-Authors: Yingjie Xu, Qin Wang, Ning Jiang, Guangming ChenAbstract:Abstract This paper presents an investigation on refrigerant evaluation and performance comparison of a novel solar-powered hybrid ejection-compression Cycle for space cooling or refrigeration. By reducing heat consumption and solar collector area, the novel ejection-compression Cycle can have better practicality and performance than Conventional hybrid ejection-compression Cycle. A model for the novel hybrid Cycle is proposed including a validated 1-D ejector model. Five refrigerants are selected from a series of candidate refrigerants and are further evaluated based on Cycle performance. Finally, R152a is recommended for its good characteristics and performance. With R152a, the novel Cycle is compared with Conventional Cycle. The results show that the novel Cycle has both higher electric efficiency (COPele) and thermal efficiency (COPth), when rationally low solar heat is provided. At low heat region and Tg = 90 °C, the novel Cycle only consumes 66.6 kW heat to increase COPele from 3.01 to 3.76, while the traditional Cycle consumes 3 times the solar heat to achieve the same COPele. When more heat is consumed, the COPele of Conventional Cycle increases. However, the increasing installation space and capital cost of increasing collector greatly reduce the practicality of Conventional Cycle. Therefore, the novel Cycle has better feasibility and good energy performance.
Mehdi Cheraghi - One of the best experts on this subject based on the ideXlab platform.
-
performance of a new two stage transcritical co2 refrigeration Cycle with two ejectors
Applied Thermal Engineering, 2019Co-Authors: Eskandari F Manjili, Mehdi CheraghiAbstract:Abstract The present study describes a new two-stage transcritical CO2 refrigeration Cycle with two ejectors (NERC). At this studied Cycle (NERC), vapor compression is performed in two stages and each vapor compression line includes separate ejector. Thermodynamic and exergetic analysis of the proposed Cycle are performed using Engineering Equation Solver (EES) software. The new Cycle (NERC) is compared with a Conventional Cycle. It is found that depended on conditions the new Cycle (NERC) improves the COP from 20% to 80% compared to the Conventional Cycle. The effects of main Cycle parameters i.e. the high-side pressure of a compressor (discharge pressure), intermediate pressure, the outlet temperature of gas cooler and evaporator temperature on COP are studied.
Peixue Jiang - One of the best experts on this subject based on the ideXlab platform.
-
particular characteristics of transcritical co2 refrigeration Cycle with an ejector
Applied Thermal Engineering, 2007Co-Authors: Jianqiang Deng, Peixue JiangAbstract:Abstract The present study describes a theoretical analysis of a transcritical CO2 ejector expansion refrigeration Cycle (EERC) which uses an ejector as the main expansion device instead of an expansion valve. The system performance is strongly coupled to the ejector entrainment ratio which must produce the proper CO2 quality at the ejector exit. If the exit quality is not correct, either the liquid will enter the compressor or the evaporator will be filled with vapor. Thus, the ejector entrainment ratio significantly influences the refrigeration effect with an optimum ratio giving the ideal system performance. For the working conditions studied in this paper, the ejector expansion system maximum cooling COP is up to 18.6% better than the internal heat exchanger Cycle (IHEC) cooling COP and 22.0% better than the Conventional vapor compression refrigeration Cycle (VCRC) cooling COP. At the conditions for the maximum cooling COP, the ejector expansion Cycle refrigeration output is 8.2% better than the internal heat exchanger Cycle refrigeration output and 11.5% better than the Conventional Cycle refrigeration output. An exergy analysis showed that the ejector expansion Cycle greatly reduces the throttling losses. The analysis was also used to study the variations of the ejector expansion Cycle cooling COP for various heat rejection pressures, refrigerant temperatures at the gas cooler exit, nozzle efficiencies and diffuser efficiencies.
Joaquin Diaz Mediavilla - One of the best experts on this subject based on the ideXlab platform.
-
bortezomib melphalan and prednisone versus bortezomib thalidomide and prednisone as induction therapy followed by maintenance treatment with bortezomib and thalidomide versus bortezomib and prednisone in elderly patients with untreated multiple myelo
Lancet Oncology, 2010Co-Authors: Mariavictoria Mateos, Albert Oriol, Joaquin Martinezlopez, Norma C Gutierrez, Anaisabel Teruel, Raquel De Paz, Jose Garcialarana, Enrique Bengoechea, Alejandro Martin, Joaquin Diaz MediavillaAbstract:Summary Background Bortezomib plus melphalan and prednisone (VMP) is significantly better than melphalan plus prednisone alone for elderly patients with untreated multiple myeloma; however, toxic effects are high. We investigated a novel and less intensive bortezomib-based regimen to maintain efficacy and to reduce toxic effects. Methods Between March, 2006, and October, 2008, 260 patients with untreated multiple myeloma, 65 years and older, from 63 Spanish centres, were randomly assigned to receive six Cycles of VMP (n=130) or bortezomib plus thalidomide and prednisone (VTP; n=130) as induction therapy, consisting of one Cycle of bortezomib twice per week for 6 weeks (1·3 mg/m 2 on days 1, 4, 8, 11, 22, 25, 29, and 32), plus either melphalan (9 mg/m 2 on days 1–4) or daily thalidomide (100 mg), and prednisone (60 mg/m 2 on days 1–4). The first Cycle was followed by five Cycles of bortezomib once per week for 5 weeks (1·3 mg/m 2 on days 1, 8, 15, and 22) plus the same doses of melphalan plus prednisone and thalidomide plus prednisone. 178 patients completed the six induction Cycles and were randomly assigned to maintenance therapy with bortezomib plus prednisone (n=87) or bortezomib plus thalidomide (n=91), consisting of one Conventional Cycle of bortezomib for 3 weeks (1·3 mg/m 2 on days 1, 4, 8, and 11) every 3 months, plus either prednisone (50 mg every other day) or thalidomide (50 mg per day), for up to 3 years. Treatment codes were generated with a computerised random number generator, and neither participants nor study personnel were masked to treatment. The primary endpoint was response rate in induction and maintenance phases. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00443235. Findings In the induction phase, 105 (81%) patients in the VTP group and 104 (80%) in the VMP group achieved partial responses or better (p=0·9), including 36 (28%) and 26 (20%) complete remissions, respectively (p=0·2). Treatment with VTP resulted in more serious adverse events (40 [31%] vs 20 [15%], p=0·01) and discontinuations (22 [17%] vs 15 [12%], p=0·03) than did treatment with VMP. The most common toxicities (grade 3 or worse) were infections (one [1%] in the VTP group vs nine [7%] in the VMP group), cardiac events (11 [8%] vs 0), and peripheral neuropathy (nine [7%] vs 12 [9%]). After maintenance therapy, the complete remission rate was 42% (40 [44%] patients in complete remission in the bortezomib plus thalidomide group, 34 [39%] in the bortezomib plus prednisone group). No grade 3 or worse haematological toxicities were recorded during maintenance therapy; two (2%) patients in the bortezomib plus prednisone group and six (7%) in the bortezomib plus thalidomide group developed peripheral neuropathy. Interpretation Reduced-intensity induction with a bortezomib-based regimen, followed by maintenance, is a safe and effective treatment for elderly patients with multiple myeloma. Funding Pethema (Spanish Program for the Treatment of Hematologic Diseases).
Yingjie Xu - One of the best experts on this subject based on the ideXlab platform.
-
exergetic and economic analyses of a novel modified solar heat powered ejection compression refrigeration Cycle comparing with Conventional Cycle
Energy Conversion and Management, 2018Co-Authors: Yingjie Xu, Mengjie Song, Qin Wang, Ning Jiang, Guangming ChenAbstract:Abstract In this paper, a novel modified ejection-compression refrigeration Cycle is studied and compared with Conventional ejection-compression refrigeration Cycle based on exergetic and economic analyses. The novel Cycle is expected to improve the low practicability of Conventional ejection-compression Cycle with better thermal efficiency, smaller solar collector and more excellent economic performance. Energy performance is simply evaluated based on thermal efficiency and global coefficient of performance. The results show the novel Cycle is better in both the two indicators, which confirmed that it needs much less solar heat and smaller collector, and has better practicability. With the above data, exergy analysis is performed, showing the total exergy destruction of the novel Cycle is 23.97 kW less than a Conventional Cycle and exergy efficiency of the novel Cycle is always higher than the Conventional Cycle in the studied range. Economic analyses taking into consideration the impact of carbon dioxide emission are finished under base case. The results reveal the novel Cycle has a total cost rate 24.4% lower and a solar collector 89.5% smaller than those of a Conventional Cycle. The economic advantage of the novel Cycle will remain, even both electricity price and carbon dioxide penalty cost increase to 3.1 times of the current price. These improvements in energy and economy indicate the novel Cycle has an excellent application potential.
-
refrigerant evaluation and performance comparison for a novel hybrid solar assisted ejection compression refrigeration Cycle
Solar Energy, 2018Co-Authors: Yingjie Xu, Qin Wang, Ning Jiang, Guangming ChenAbstract:Abstract This paper presents an investigation on refrigerant evaluation and performance comparison of a novel solar-powered hybrid ejection-compression Cycle for space cooling or refrigeration. By reducing heat consumption and solar collector area, the novel ejection-compression Cycle can have better practicality and performance than Conventional hybrid ejection-compression Cycle. A model for the novel hybrid Cycle is proposed including a validated 1-D ejector model. Five refrigerants are selected from a series of candidate refrigerants and are further evaluated based on Cycle performance. Finally, R152a is recommended for its good characteristics and performance. With R152a, the novel Cycle is compared with Conventional Cycle. The results show that the novel Cycle has both higher electric efficiency (COPele) and thermal efficiency (COPth), when rationally low solar heat is provided. At low heat region and Tg = 90 °C, the novel Cycle only consumes 66.6 kW heat to increase COPele from 3.01 to 3.76, while the traditional Cycle consumes 3 times the solar heat to achieve the same COPele. When more heat is consumed, the COPele of Conventional Cycle increases. However, the increasing installation space and capital cost of increasing collector greatly reduce the practicality of Conventional Cycle. Therefore, the novel Cycle has better feasibility and good energy performance.