Compression Refrigeration Cycle Research Articles

Techno-economic analysis of blue ammonia synthesis using cryogenic CO2 capture Process-A Danish case investigation

Ammonia is a vital chemical with numerous applications. Currently, the primary methods for generating the necessary reactants for ammonia production involve steam methane reforming (SMR) and cryogenic air separation unit (CASU), while the Haber-Bosch process converts these reactants into ammonia. However, the SMR process releases substantial amounts of CO2, making it imperative to employ an efficient and cost-effective CO2 capture technology to mitigate emissions. This investigation focuses on evaluating the cryogenic CO2 capture (CCC) process for blue ammonia production and provides a thorough economic analysis, estimating both the initial investment costs and operational expenses involved in producing blue ammonia. The results indicated that the CCC process can capture 90% of the CO2 content in the flue gas emitted by the SMR, incurring an energy penalty of 0.724 MJe/kgCO2 while capturing CO2 in the liquid phase with purities exceeding 99.9%. In this case, the estimated CO2 capture costs would be 18.05, 45.1, and 16.65 USD/ton in 2021, 2022, and 2023, respectively. This represents a 40% reduction compared to the CO2 capture costs associated with conventional amine-based technology. The results of this study indicate that the annual electricity costs for ammonia production increase by 38.5% and 64.2% when employing the CCC and amine-based processes, respectively. This investigation employed an isothermal reactor for ammonia synthesis, using the heat from the exothermic reaction in a water ammonia absorption refrigeration cycle (ARC) to condense and purify ammonia. The results show that the ARC system can effectively condense ammonia at −6 °C, producing a liquid ammonia stream with 99.3% purity. This leads to a 95% reduction in power consumption compared to a vapor compression refrigeration cycle (VCRC). Consequently, this method has the potential to decrease the annual operational costs for ammonia production by 2.92%, 2.69%, and 3.13% in 2021, 2022, and 2023, respectively. This study indicated that the hydrogen production unit incurs the highest initial investment costs, as well as operating costs, in the blue ammonia production process, followed by CASU and the Haber-Bosch process.

Thermodynamic performance analysis and environmental impact assessment of cascade refrigeration cycles using eco-friendly nano-refrigerants

There is a lack of research in the literature on the application of nanoparticles to different cascade cycle configurations with environmental refrigerants in ultra-low temperature refrigeration applications. This study is the first on the use of nano-refrigerants in cascade refrigeration cycles. In this study, the effect of 2 wt.% of CuO to RE170 and R170-pure refrigerant utilization in cascade vapor compression refrigeration cycle (CVCRC), cascade ejector refrigeration cycle (CERC) and cascade ejector intercooler refrigeration cycle (CEIRC) are investigated to achieve higher performance values in ultra-low temperature applications. For CVCRC, CERC and CEIRC, the increases in terms of coefficient of performance (COP) with the use of nano-refrigerant were found to be 12.77 %, 8.20 %, and 6.37 %, respectively, and 18.55 %, 14.05 %, and 6.07 %, for exergy efficiency. Upon scrutinizing the results with nano-refrigerant in relation to the COP, the analysis revealed that the CEIRC cycle exhibited an improvement ranging from 13.43 % to 20.49 % in comparison to CERC. Additionally, with nano-refrigerant, the CEIRC cycle demonstrated an increase ranging from 42.39 % to 75.41 % when compared to CVCRC in COP. It was observed that the utilization of CEIRC led to a 13.03 % decrease in kg CO2 emissions in compared to CERC and a reduction of 32.53 % compared to CVCRC with using nano-refrigerant.

Compression-assisted absorption refrigeration cycle employing organic working pairs for ultra-low grade heat recovery

Solar absorption refrigeration technology is considered an ideal alternative to energy-intensive refrigerated warehouses due to its decarbonization and environmental friendliness. However, it faces challenges in competing with vapor compression refrigeration, such as high driving heat source temperature (>100°C) and a long payback period. In this paper, we address these challenges by focusing on cycle structure and working pair, and propose a compression-assisted absorption refrigeration cycle (CARC) using R32/dimethylacetamide (DMAC) as working pair. The aim is to significantly reduce driving heat source temperature by adjusting absorption pressure utilizing an auxiliary compressor, enabling the cycle to be connected to low-cost and efficient non-concentrating solar collectors, thereby effectively shortening its payback period. This cycle includes two operating modes: CARC mode powered by solar energy during the daytime and vapor compression refrigeration cycle mode driven by off-peak electricity at night, ensuring 24-hour cooling capacity for refrigerated warehouses. The results indicate that this cycle can flexibly utilize 60∼80°C solar hot water easily obtained as driving heat source and its evaporation temperature decreases to -20°C. To assess its performance benefits, a compression-assisted absorption refrigeration system is developed and implemented. By utilizing the limited roof area of a refrigerated warehouse, it can achieve an 18.2% reduction in electricity consumption and a 24.2% reduction in carbon emissions compared to the vapor compression one annually. Additionally, during peak electricity demand periods in summer, the system exhibits significant energy-saving effects, and its payback period is about 4.2 years. Ultimately, this cycle provides a viable solution for energy-saving and emission reduction in refrigerated warehouses.

Thermal analysis of solar energy based organic Rankine cycle cascaded with vapor compression refrigeration cycle

The air conditioning and refrigeration applications use a significant portion of the electrical energy. This research analyses a performance of refrigeration system, which comprises on different configurations of solar based organic Rankine cycle (ORC) and vapor compression refrigeration (VCR) cycles requiring low evaporation temperatures. In this research, the dry natural hydrocarbons such as n-Decane, n-Dodecane and Toluene have been chosen to serve as the working fluids in ORC. Whereas in VCR cycle natural hydrocarbons such as Ethane, Propane, isobutane, isopentane and isohexane have been used because traditional working fluids have a negative environmental impact due to high values of ozone depletion and global warming potential. The simulated results showed that the facility can be operated efficiently with the use solar thermal energy resources within the temperature range 90 to 315ºC and decreasing the need for conventional fossil fuel resources. It was also revealed that the highest efficiency was achieved by n-Dodecane in regenerative ORC, which is 35.34 % at the evaporation temperature of 315ºC and the highest overall coefficient of performance (COPoverall) in regenerative ORCCRS facility was achieved by n-Dodecane in ORC and isopentane in refrigeration cycle which is 1.017 while in case of Simple ORC–VCR facility the highest COPoverall was achieved by Toluene in ORC and isopentane in refrigeration cycle, which is 0.7174 at the evaporation temperature 315ºC.

Parametric analysis for nanolubricant in vapor compression refrigeration cycle

With the escalating global energy crisis and the consequential surge in energy consumption, particularly attributed to air conditioning (AC) systems in buildings, there arises a pressing need for sustainable solutions to mitigate this escalating demand. Vapor compression refrigeration (VCR) cycles, ubiquitous across residential, commercial, and industrial sectors, represent a significant portion of global electricity consumption, exceeding 10%. This demand is further exacerbated in regions characterized by hot climates. Consequently, there is a critical imperative to address the environmental impact of these systems, particularly in terms of reducing their Global Warming Potential (GWP). In response to this imperative, this study aims to develop a comprehensive numerical model for VCR systems, focusing on the implementation of nanolubricants. The primary objective is to assess the impact of integrating Al2O3 nanoparticles into the lubricating oil (referred to as nanolubricant) on the performance of the VCR cycle. The scope of the study encompasses the investigation of nanolubricants within refrigeration systems, aiming to enhance their efficiency and environmental sustainability. Utilizing the Engineering Equation Solver (EES), a numerical model of a VCR cycle utilizing R-410A refrigerant is developed. The model specifically emphasizes the compressor component, which is flooded with a polyolester (POE) oil base. The study explores various parameters, including ambient conditions, refrigerant-to-oil dissolving ratio, and mass concentration of nanoparticles, to evaluate their influence on system performance. The results indicate a significant enhancement in performance when flooding the base oil before introducing Al2O3 nanoparticles, with further improvements observed upon nanoparticle integration. Specifically, the coefficient of performance (COP) of the VCR system exhibits a notable increase compared to the base case configuration. Additionally, the adoption of eco-friendly refrigerants, such as R-32, demonstrates promising COP values following nanoparticle implementation by up to 4%. Moreover, the study reveals a reduction in compressor discharge temperature by up to 20% with higher oil mass concentrations during nanolubricant implementation, indicating enhanced durability and longevity of the VCR system’s compressor. These findings underscore the potential of nanolubricants to contribute to both the efficiency and environmental sustainability of refrigeration systems. In conclusion, the findings of this study offer valuable insights into the utilization of nanolubricants in VCR cycles, highlighting their potential to enhance system performance and mitigate environmental impact. These advancements hold promise for the development of more sustainable refrigeration technologies in the face of mounting energy challenges.

High-pressure liquid refrigerant injection for reciprocating compressors

Isentropic (adiabatic) compression of superheated vapor in vapor compression refrigeration cycles usually results in some discharge superheat, i.e. the discharge temperature exceeding the condensing temperature. Large discharge superheat reduces both operating range and compression efficiency. Sub-isentropic compression with heat rejection to the heat sink is therefore superior to adiabatic compression, as it results in lower discharge superheat and improved efficiency. However, significant temperature reduction by heat transfer through the working chamber walls is difficult to facilitate in common refrigeration compressors, particularly reciprocating compressors. Refrigerant and oil injection is a well-established method for reducing temperatures and increasing efficiency in screw and scroll compressors, as well as multi-stage systems. In comparison, effective methods for temperature reduction in single-stage reciprocating compressors are fairly limited. Therefore, a concept for high-pressure liquid injection is proposed. By means of a pump and injection valve, high-pressure liquid refrigerant is injected into the working chamber and atomized. The compressed gas is cooled through the evaporation of the injected liquid. The injection valve allows for control over the injection timing and quantity, enabling adjustment of the temperature profile, which is a major distinction from existing refrigerant injection methods. The coupled compression-injection process is evaluated for various refrigerants using an energetic chamber model. The injection is found to be particularly suitable for refrigerants with a large evaporation heat and a shallow dew line slope. For the example of ammonia, a theoretical reduction in compression work of 8.9% at an evaporation temperature of −10 °C and a condensing temperature of 45 °C is found.

Analysis of the Vapor Compression Refrigeration Cycle Measures with and without Using a Heat Exchanger for Alternative Refrigerants

One of the most commonly refrigeration systems is the vapor compression refrigeration system. Since energy saving and environmental friendliness remain a challenge, researchers are working hard to find an effective solution to improve the performance of vapor compression refrigeration systems while committing to environmental standards. The main goal of this paper is to identify the best and closest alternative refrigerant to R22 among the alternative cooling fluids taken into consideration in terms of thermodynamic and mechanical properties, environmental protection, and safety of handling. This work presents an analysis and comparison of the various performance measures for a vapor compression refrigeration cycle operating without using and using a heat exchanger for environmentally friendly alternative refrigerants, namely R410A, R407A, R407C, R438, RS-44b, and R417A, and compares them with the refrigerant R22, which has direct environmental impacts on the ozone layer (ODP) and global warming (GWP). The computer simulation program Chemours Refrigerant Expert 1 was used to conduct the analyses. The performance parameters analyzed are coefficient of performance, compressor work, cooling capacity, temperature of condensation, intake and exhaust pressure, volumetric capacity, theoretical displacement, intake, exhaust, condensation and evaporation temperature without and with a heat exchanger, and super heating temperature with a heat exchanger. It was concluded from this study that the best alternative to R22 refrigerant among the alternative refrigerants taken into consideration in the study is the RS-44b refrigerant in terms of all performance measures and environmentally friendly. Keywords: Refrigerant; Vapor compression; Performance measures; Evaporation; Heat exchanger.

4E analysis and triple objective NSGA-II optimization of a novel solar-driven combined ejector-enhanced power and two-stage cooling (EORC-TCRC) system

This study proposed an innovative combined ejector-enhanced organic Rankine cycle and two-stage compression refrigeration cycle (EORC-TCRC), to investigate its potential to revolutionize energy utilization and offer a sustainable solution for the current energy challenge. Energy, exergy, economic, and environmental (4E) analysis of the novel EORC-TCRC system was conducted first. The performance appraisal of the novel system compared to the conventional combined power and ejector refrigeration system has been evaluated. The evolutionary non-dominated Sort Genetic (NSGA-II) optimization algorithm was implemented to ascertain triple-objective optimal system operating conditions. The results revealed a significant improvement in refrigeration output, energy, and exergy efficiency with values of 220.06 kW, 11.67%, and 17.07%, respectively, compared to the conventional Rankine power and ejector refrigeration system. By different selections of the objective functions, four groups comprised of Multi-Objective CT–ղex, Multi-Objective CT–ղTh, Multi-Objective ղex–ղTh, and Triple-Objective mode presented to sought NSGA-II optimization results. The optimization results of Multi-Objective CT–ղTh mode indicated that the best thermal efficiency and overall system cost rate operating conditions are 28.25% and 78,820 ($/year), respectively. While the optimal system operating condition occurs in the Triple-Objective ղex- ղTh-CT with the exergetic efficiency of 41.69%.

Energy efficiency optimization analysis for a cooling composite air conditioning system for internet data centers

In this study, a validated mathematical model for a composite air conditioning system was established based on onsite test data. The system consists of a refrigerant pump driven two-phase cooling loop (RPTCL) and vapor compression refrigeration (VCR) cycles. The system can be switched to refrigerant pump (RP) mode, compressor mode, or hybrid mode, according to the outdoor temperature. By analyzing, the inadequacy of the existing Internet Data center (IDC) air conditioning system operation strategy was confirmed, and subsequently, five optimization strategies were proposed. The optimization strategies took two identical composite air conditioning systems as optimization unit, and under the premise of meeting the demand for cooling capacity, maximizing the operating time of RP and hybrid mode, which with higher energy efficiency, through complementary cooling capacity, to reduce the energy consumption. Meanwhile, when the cooling supply was higher than the demand, paired with optimization unit’s ON/OFF ratio control, the unit’s energy consumption was further reduced. The most optimization strategy provided 525.6 MWh of cooling energy to meet demand while consuming a minimum of 182.5 MWh. The optimization strategy also achieved a minimum of 12.1% and a maximum of 52.5% energy savings for IDCs in other climate zones of China.

Assessment of the use of solar energy sources and cooling seawater in a combination of a basic and two-stage regenerative organic Rankine cycle with a vapor compression refrigeration cycle

Assessment of the use of solar energy sources and cooling seawater in a combination of a basic and two-stage regenerative organic Rankine cycle with a vapor compression refrigeration cycle

Performance Analysis of Atmospheric Water Extraction by Refrigerator Cum Air Conditioner

India is blessed with warm and humid climatic conditions in most of its states containing huge amount of water in atmosphere which can fulfill the increasing water demands. Atmospheric water extraction is one of the technologies where fresh water is obtained from the ambient air by condensation. The atmospheric water extracting device is working on vapour compression refrigeration cycle. In this cycle the evaporator inlet temperature is maintained at a temperature lower than the dew point temperature of the atmospheric incoming air. Therefore, the moisture present in the air condenses over the coil and it will be collected. The amount of condensate depends on psychrometric conditions of incoming air. The present work concludes that atmospheric water extracting devices are most effective in hot and humid regions. when the humidity level in atmosphere is being 56%, 8.3ml/min water is extracted and when the humidity level in atmosphere is being 36%, 1.7ml/min water is extracted.

Performance of hybrid vaccine freezer that combined thermoelectric coolers with vapor compression refrigeration: Experimental assessment

AbstractIn the medical field, refrigeration systems are used to store and transport vaccines, blood, and other medical supplies that require specific temperature ranges to remain effective. As technology continues to advance, the demand for more efficient and sustainable refrigeration systems is also increasing. The freezer compartment is typically designed to maintain a temperature of −18°C to −23°C for storing frozen items. Consequently, this work aims to develop a hybrid refrigeration system that combines a thermoelectric cooler system (TEC) and a vapor compression refrigeration cycle (VCC) system to achieve lower temperatures than conventional refrigerators. Also, the performance of the proposed hybrid refrigeration system is experimentally assessed with various operating conditions, including varying the voltage delivered to the system. The experimental results exhibited that the temperature inside the freezer room reached −33°C, while the cold side temperature is −47°C. Also, the maximum coefficient of performance of the VCC system, TEC, and hybrid system is 2.07, 1.06, and 0.37, respectively, at a DC voltage applied of 6 V. Moreover, the results revealed that the hybrid system combining a TEC and a VCC system can be a valuable technology for specific applications with low temperatures and limited capacity requirements.

Experimental analysis of the temperature distribution inside vaccine freezer compartment based on hybrid refrigeration system

Recently, the demand for refrigeration globally has been increasing in the fields of vaccine storage, medical services, food preservation, and cooling for electronic components. This has resulted in the generation of more electrical power and thus releasing more CO2 around the world which has led to many climatic changes, such as global warming. The vapour compression refrigeration cycle (VCC) is the most common as it has a high coefficient of performance (COP), although it only operates down to temperatures of around −20 °C. The thermoelectric cooler (TEC) modules offer a featured method for cooling technology, which is not mainly considered by energy efficiency but offers distinctive merits in specific applications. Although the TEC system is not conventionally known for incomparable energy efficiency, it offers a range of exceptional attributes that make it a desirable option for certain scenarios. Therefore, this work aims to assess the performance of the innovative hybrid vaccine freezer system depending on how well the VCC system and the TEC work together. Also, the temperature distribution within the freezer compartment has been investigated under various operating conditions. The newly developed hybrid vaccine refrigerator system consists of four pieces of TEC-12706 modules that function well at low temperatures. The results indicate that the best coefficient of performance (COP) of 1.05 is achieved with a total power consumption of 172.8 W when the TEC is operating at 5.5 V and the fan is running at 12 V. The cooling capacities of the freezer and cooler compartments are 9.2 W and 165 W, respectively. Furthermore, the best distribution and lowest temperatures were obtained, with temperatures in the lateral area of −40 °C compared with −37 °C in the central area.

Study of an integrated vortex tube used in hydrogen pre-cooling system

In hydrogen refueling stations, a hydrogen pre-cooling system is essential to protect the onboard hydrogen storage cylinder from high-temperature damage during refueling. To address the high power consumption of existing systems, this study proposes an integrated vortex tube hydrogen pre-cooling system. This system combines the vortex tube with a two-stage compression refrigeration cycle to create a new refrigeration device. The vortex tube component is numerically simulated using the standard k-ε turbulence model. Comparative analysis of power consumption and coefficient of performance (COP) is conducted between the new system, single-stage, and two-stage hydrogen pre-cooling systems. The results indicate that the vortex tube, as the pressure ratio increases from 1.5 to 20, reduces power consumption by 26.37%–41.52% compared to the single-stage system. Additionally, it improves the COP by 30.9%–53.8% compared to the single-stage system. Furthermore, compared to the two-stage system, the vortex tube achieves power savings of 4.08%–10.44% and COP improvements of 4.3%–11.7%.

Exergoeconomic Analysis of a Mechanical Compression Refrigeration Unit Run by an ORC.

To improve the efficiency of a diesel internal combustion engine (ICE), the waste heat carried out by the combustion gases can be recovered with an organic Rankine cycle (ORC) that further drives a vapor compression refrigeration cycle (VCRC). This work offers an exergoeconomic optimization methodology of the VCRC-ORC group. The exergetic analysis highlights the changes that can be made to the system structure to reduce the exergy destruction associated with internal irreversibilities. Thus, the preheating of the ORC fluid with the help of an internal heat exchanger leads to a decrease in the share of exergy destruction in the ORC boiler by 4.19% and, finally, to an increase in the global exergetic yield by 2.03% and, implicitly, in the COP of the ORC-VCRC installation. Exergoeconomic correlations are built for each individual piece of equipment. The mathematical model for calculating the monetary costs for each flow of substance and energy in the system is presented. Following the evolution of the exergoeconomic performance parameters, the optimization strategy is developed to reduce the exergy consumption in the system by choosing larger or higher-performance equipment. When reducing the temperature differences in the system heat exchangers (ORC boiler, condenser, and VCRC evaporator), the unitary cost of the refrigeration drops by 44%. The increase in the isentropic efficiency of the ORC expander and VCRC compressor further reduces the unitary cost of refrigeration by another 15%. Following the optimization procedure, the cost of the cooling unit drops by half. The cost of diesel fuel has a major influence on the unit cost of cooling. A doubling of the cost of diesel fuel leads to an 80% increase in the cost of the cold unit. The original merit of the work is to present a detailed and comprehensive model of optimization based on exergoeconomic principles that can serve as an example for any thermal system optimization.

Thermodynamic and Environmental Analysis of Novel Cascade Refrigeration Cycles with Ejector and Intercooler for Ultralow Temperatures Using Eco‐Friendly Refrigerants

The present study introduces a novel cascade ejector intercooler refrigeration cycle (CEIRC) and a novel cascade ejector booster refrigeration cycle (CEBRC), which are designed to improve ultralow temperature (ULT) refrigeration system performance based on various refrigerants in terms of energy, exergy, and environment. Through the analysis conducted with eco‐friendly refrigerants for CEIRC, the refrigerant pair exhibits the highest performance that is found to consist of RE170 for high‐temperature cycles and R170 for low‐temperature cycles. These refrigerants have very low global warming potential and are eco‐friendly. The coefficient of performance (COP) reveals improvements of 3.20–9.51%, 10.55–19.12%, and 31.96–65.97% over the CEBRC, cascade ejector refrigeration cycle (CERC), and cascade vapor compression refrigeration cycle (CVCRC), respectively, resulting in corresponding exergy efficiency improvements of 3.18–9.49%, 10.48–19.12%, and 31.87–65.98%. The total compressor power and exergy destruction are also compared, indicating that the CEIRC exhibits the best performance among the four. CEIRC achieves a COP increase of 11.6% compared with the cascade refrigeration cycle, which is considered the cycle with the highest performance operating at ultralow temperatures in the literature, which is CERC. The kg CO2 effect of the CEIRC is 11.35% lower than that of the CERC.

Ultra-Low-Temperature Refrigeration Systems: A Review and Performance Comparison of Refrigerants and Configurations

During the last decade, many industrial and medical applications have shown a requirement for low-temperature-cooling usage (from −40 to −80 °C), which cannot be efficiently obtained via the conventional refrigeration systems usually employed for medium-temperature applications (from 0 to −40 °C). A proper ultra-low-temperature (ULT) refrigeration system design is essential to achieve the desired output. The performance can be maximised via the suitable selection of the configuration and refrigerant for a specific temperature range. This work contributes a detailed overview of the different systems and refrigerants used in ultra-low-temperature applications. Different systems, such as single-stage vapour compression, multi-stage, cascade, auto-cascade, and air refrigeration cycles, are presented and discussed. An energy analysis is then carried out for these systems identifying the optimal system design and refrigerant selection to achieve the highest performance. This paper aims to provide the reader with a comprehensive background through an exhaustive review of refrigeration systems suitable for ultra-low-temperature applications. The effectiveness of these systems is proven numerically, mainly based on the temperature level and purpose of the application.

Simulation of vapour compression air conditioning system using Al2O3 based nanofluid refrigerant

The energy crisis, Greenhouse Gas (GHG) emissions, and Chlorofluorocarbon (CFC) emis-sions are major environmental issues at present. It is critical to achieve and reduce emissions and energy consumption through the use of environmentally friendly refrigerants. Utilizing an environmentally friendly refrigerant such as HFC-32 may offer a viable solution to the ozone depletion potential (ODP) and global warming issues. This study examines the effects of aluminium oxide (Al2O3) nanoparticles at volume concentrations of 0.06, 0.08, 0.1, 0.12, 
 and 0.14% in pure refrigerants such as HFC-32 and R-410a used in air-conditioning systems based on the vapour compression refrigeration cycle. The thermophysical properties of pure and nanorefrigerants have been determined using REFPROP (NIST properties of fluid Refer-ence) and a theoretical formulation model using MATLAB software. The important outcomes of HFC-32 nanorefrigerant show the maximum performance with 0.14% alumina nano addi-tives which results in a 46.14% increase in the coefficient of performance (COP) and massive power savings upto 31.59%. Thermal conductivity exhibited an increase with an increment in nanoparticle concentration. Maximum thermal conductivity of 0.172 W/m-K is recorded 
 in the case of HFC-32/Al2O3 nanorefrigerant with 0.14% volume concentration. The net re-frigeration effect of pure refrigerants (R410a and HFC-32) is 77% and 79% and on addition of nanorefrigerants to the pure the net refrigeration effect increases to 81.2% and 83.5% for R410a and HFC-32 respectively.

Multicriteria study of geothermal trigeneration systems with configurations of hybrid vapor compression refrigeration and Kalina cycles for sport arena application

Among the famous renewable energy sources all around the world, geothermal heat is known to be accessed plentifully. The present paper investigates three geothermal cycles in the viewpoint of the first and second laws of thermodynamics, exergoeconomic, and exergoenvironmental analysis. The provided cycles, A, B, and C are trigeneration cycles with power, cooling load, and domestic hot water as products. The final system is theoretically customized to sustain a sport facilitation. The proposed cycles were simulated by EES software and validated by reliable references. The investigations demonstrate that considering thermodynamics’ first and second law, cycle C has the best performance compared to cycles A and B with acceptable functionality on an exergoeconomic standpoint. For cycle C, energy efficiency, exergy efficiency, and net output power were calculated as 69.75 %, 29.79 %, and 68.8 kW, respectively. The exergoeconomic analysis of cycle C revealed the cost of product and exergy destruction as 160.4$/GJ and 150.45 kW, respectively. An exergoenvironmental study was compiled to study the effects of the system on the environment with respect to associated environmental parameters. A 3D multi-objective optimization was performed to identify the optimal condition with respect to target parameters. The purpose of the current system is to sustain a sport arena.

Design and Building of a Two-Stage Cascade Refrigeration System for Storage of Blood Plasma

Daily life-saving transfusions rely on the usage of blood products in clinical and research settings. With its proteins used for replacement treatment, human blood plasma serves as the main source for a variety of therapeutic transfusions. During the COVID-19 pandemic, plasma-based therapy was one of the treatment modalities used to treat infectious infections and as a source of neutralizing antibodies in patients. The specialty of transfusion medicine was adversely impacted and faced a stockpile shortage because plasma must be quickly frozen within six hours of collection in order for its proteins and coagulation components to be of the optimum quality. As a result, the cascade refrigeration system is an innovative technology that can provide the required ultra-low freezing temperature and maintain the same temperature in storage for plasma management. The paper concentrated on the design and construction analysis of a two-stage cascade refrigeration system for quick freezing time, and storing plasma proteins at extremely low temperatures to prolong their limited shelf life in a sensitive, temperature-controlled storage system. The choice of refrigerants R404A and R410A is made for high temperature and low temperature circuits which are carefully selected based on study and analysis of the characteristics of different refrigerants for short-term freezing. The ultra-low temperature evaporator is achieved using a blend of two vapour compression refrigeration cycles thermally connected by a heat exchanger to produce a freezing temperature of -35 0C. For analysis, the system was charged with various weights of plasma weighing between 1 kg and 4 kg for two hours and a half hour and kept at a temperature of -35 0C. The system's dependability and practicality for extending plasma shelf life were assessed. After 72 hours of temperature-controlled storage, the results showed 75% efficiency and a negligible (0.4) plasma quality drop.