Tank Size Research Articles

A transient heat losses model for two-tank storage systems with molten salts

Concentrating Solar Power (CSP) is a proven and mature technology for energy supply. In recent years, electricity generation based on this technology has increased worldwide, to a large degree due to its high dispatchability when coupled with an energy storage system. Commercially, most plants store the energy in molten salts in a two-tank configuration. This study focuses on this storage configuration and proposes a mathematical model for the thermal losses in these tanks, both at nominal conditions and during transients. With this model at its core, a computational tool for thermal performance analysis in OpenModelica is developed. This dynamic thermal model includes the estimation of local heat loss due to assembly defects, which are heat flows that cannot be determined by theoretical modelling. The development of a semi-empirical correlation for estimating local heat loss is also presented. Simulation results showed that this local heat loss may represent a share about 40% of the total heat loss in a small-scale tank. A comparison of the characteristics of the model proposed in a previous work is also presented to establish the innovation of the model. Two thermal storage systems with different tank designs and sizes were simulated to compare the results using the present model with data available in the literature. Results show good agreement in transient thermal behaviour of heat flows, temperatures, and cooling rates when compared with data from other authors for the same tank.

Techno-economic feasibility of various types of solar collectors for solar water heating systems in hot and semi-arid climates: A case study

The pursuit for sustainability and a reduction in reliance on non-renewable energy sources has fueled the growing use of solar energy systems worldwide. This study assesses the feasibility of using domestic solar heating systems in Kirkuk, Iraq. The study utilized T*SOL software focused on three different solar collector systems: Thermital, Eraslan, and Apricus, chosen based on their type of collector loop (open loop or closed loop), type of collector (flat plate or evacuated tube), and collector size. The impact of varying the size of the hot water storage tank was also analyzed. The aim was to find a cost-effective solution that maximizes energy efficiency, reduces initial and maintenance costs, and cuts CO2 emissions. The results of the economic analysis showed that the energy demand for the case study was 1430 kWh. Both open loop and closed loop systems were found to achieve a solar fraction of 86% using evacuated tube collectors, but the open loop system required a smaller storage tank. The amount of CO2 emissions avoided was estimated to be between 689.5 and 1316 kg/year. The study concludes that domestic solar heating systems in Kirkuk, Iraq offer a sustainable and cost-effective energy solution, eliminating the need for an electrical water heater and resulting in substantial energy savings.

Teaching differential equations through modelling: hot water heater

We present an example of one of the modelling projects we assign to students in our differential equations classes. Students are asked to determine how to run a cost-efficient hot water heating system. We consider a cylindrical tank filled with water and heated by a heating element immersed in it. Together with students we discuss physical laws governing the process and make assumptions necessary to build a model. One of the goals of the modelling activity is to compute the time needed for water to reach the desired temperature given the power of the heating element and the size of the water tank. Several different scenarios can be discussed. Assuming the cost of heating the water is directly related to the time for which the power is ON, students can choose the most cost-efficient scenario. We provide the description of several modelling activities and obtained results.

Performance Simulation Model of a Radiation-Enhanced Thermal Diode Tank-Assisted Refrigeration and Air-Conditioning (RTDT-RAC) System: A Novel Cooling System

This paper presents a novel technology to improve the energy efficiency of refrigeration and air-conditioning (RAC) systems by applying a condenser cooling approach. The approach is based on the integration of an innovative radiation-enhanced thermal diode tank (RTDT) with a RAC system. The thermal diode tank (TDT), consisting of heat pipes and an insulated water tank, is a passive device to generate cooling water at a minimum night ambient temperature. When the radiation-enhanced heat pipe (RHP) is equipped with the TDT, it becomes an RTDT, which could theoretically lower the water temperature below the ambient temperature. In this study, a radiation-enhanced thermal diode tank (RTDT) is proposed to supply cooling water to the RAC system. Simulation models for the proposed RTDT-assisted RAC (RTDT-RAC) system are developed in order to investigate the impacts of the tank size to cooling capacity (TS/Qc) ratio, day/night ambient temperature fluctuations on the system’s coefficient of performance (COP) and the energy saving percentage (ESP). The results show that a greater day/night ambient temperature difference and a larger TS/Qc value can both enhance the COP and ESP of the RTDT-RAC system. The optimal and threshold TS/Qc values were 1 m3/kW and 0.18 m3/kW, respectively. These findings demonstrate the potential of the RTDT-RAC system to achieve significant energy savings and provide valuable insights for the design and optimization of an RTDT-RAC system.

Scaling of groundwater flow subject to managed aquifer recharge using injection boreholes: Physical experiments and upscaled numerical models

Managed aquifer recharge (MAR) holds great promise for solving the issue of groundwater resource depletion and quality deterioration in urban areas, but the scaling of groundwater flow patterns under MAR influence from controlled laboratory experiments to complex field scale conditions has not been fully resolved. This study applied physical and numerical groundwater flow experiments at the laboratory scale (100 m) along with ten numerical models at increasing spatial scales (100–103 m) for porous media representative of unconsolidated sand aquifers. We considered several spatial and temporal features that characterize groundwater flow patterns, such as the water table elevation, the thickness of the capillary fringe, the MAR lens geometry (defined as formed by the plume of artificially recharged water), the locations of stagnation points (defined as the points of convergence between ambient groundwater flow and injected water flow), and the groundwater travel times, which were examined at relative scales for comparison. The analysis showed that small-scale sandbox experiments overall underestimate the magnitude of the effects of MAR on groundwater flow pathways. The trends with increasing scales for these parameters were non-linear and could be fitted to power law relationships. These trends were more prominent at scales <20 times the size of the laboratory sand tank. Importantly, the heterogeneity of the sand material, as reflected by non-uniform spatial distributions of hydraulic conductivities (K) also had a major effect on the scaling of groundwater flow patterns, even for the relatively low degree of heterogeneity considered. Specifically, an increase in the average K and its standard deviation further exacerbates the scale dependency. This study provides insights into the appropriate scaling techniques to be used when applying small scale experimental results (e.g., from laboratory) to predict MAR-induced groundwater flow dynamics at larger field scales in moderately heterogeneous, unconsolidated sands.

Optimization of Roof Coverage and Tank Size for Integrated Green Roof Rainwater Harvesting Systems-a Case Study

Optimization of Roof Coverage and Tank Size for Integrated Green Roof Rainwater Harvesting Systems-a Case Study

Conceptual design of floating storage and regasification unit (FSRU) for Eastern Part Indonesia

Liquefied Natural Gas (LNG) can be used as an alternative fuel with environmentally friendly solutions. In general, the domestic distribution of natural gas in LNG is more cost-effective than transporting gas through underwater pipelines considering Indonesia as archipelagic country. According to Indonesia’s Minister of Energy and Mineral Resources Regulation Number 13 of 2020, the government supports converting 52 power plants to LNG. However, the current challenge in the LNG industry is the lack of supporting facilities. Storage and regasification facilities are among the infrastructure that requires optimization. Floating Storage and Regasification Unit (FSRU) are viable options for energy distribution that offer opportunities and competitiveness compared to onshore terminals. Small and medium-scale FSRU can serve as an alternative solution due to their relatively fast, flexible, and affordable development process. Therefore, this research will develop a small-medium FSRU design with a capacity of 60 MW − 70 MW in Eastern Indonesia. FSRU design should consist of four segments including location considerations and environmental conditions, powerplants gas requirements, LNG storage tank sizing and LNG regasification process. Calculations for various supporting FSRU components, seakeeping analysis, loading-offloading processes, 3D modelling and the integration of solar panels were discussed. The results obtained include the principal dimension, technical aspects of FSRU design, and the technology for LNG regasification processes used.

Hydrogen Storage Using Metal-Organic Frameworks (MOFs): A Computational Fluid Dynamic Study

The existing obstacles toward the usage of fossil fuels as the prime mover of the cars have improved the commercialization of the fuel cells and batteries to replace the internal combustion engines (ICEs). Although the required infrastructure is already established for the ICE cars, the low number of hydrogen refueling stations, low range of batteries, high charging time of the batteries, and the size/weight of the hydrogen tanks are the main concerns toward the transition from ICE cars to environmentally friendly alternatives.Fuel cells can be directly used in the vehicles as the prime mover (mobility applications), or they can be considered as the energy provider of the electric vehicle charging stations (stationary applications). Although the hydrogen storage is not being considered as an obstacle for the stationary applications, the required weight and size of the hydrogen tanks is a barrier to facilitate the usage of hydrogen in the automotive sector. Based on the given standards [1], it is possible to pressurize hydrogen up to 700 bars, hence reducing the size of the hydrogen tanks. This solution has been already used in the development of the Toyota Mirai, which has 114kW/155hp power and 500km range with the fuel consumption of 0.76 kg H2/100km [2]. Similarly, Honda Clarity could reach the range of 650km with 5kg of hydrogen tank capacity at the rated power of 130kW/ 176hp [3]. Although pressurizing the hydrogen is a feasible solution, it will demand further costs and safety procedures to reach the 700 bars. In other words, the best solution would be reaching the same driving range without pressurizing the hydrogen.In this regard, Metal-Organic Framework (MOF) can be used to increase the hydrogen adsorption in the hydrogen tank due to higher gravimetric storage density. Among different types of MOFs, the MOF-5 has shown promising results to increase the hydrogen storage up to wt. 10% absolute at 70 bar and 77K. It is believed that the low thermal conductivity of the MOF-5 can reduce the performance of the system when rapid gas uptake and release is required [4]. Although there have been studies to evaluate the overall possibilities of using MOF-5 to improve the adsorption of hydrogen in the hydrogen tanks, there is not a comprehensive study to simulate and characterize the changes in the hydrogen adsorption once the hydrogen tanks are filled with different types of MOFs.The goal of this study is to use the computational fluid dynamic methodologies to model a hydrogen tank filled with MOFs and to analyze the hydrogen adsorption by the changes in the time. This study can a step toward improving the design of the hydrogen tanks, which will facilitate the hydrogen storage at low pressures close to the ambient temperatures. This study can be also a good start to find the right type of MOF to be used in the hydrogen tanks to have the highest possible hydrogen adsorption. The developed model is based on mass, momentum, and energy conservation equations of the adsorbent-adsorbate system composed of gaseous and adsorbed hydrogen, adsorbent bed and tank wall. It is noteworthy to mention that the adsorption process is based on the modified Dubinin-Astakov (D-A) adsorption isotherm model. Keywords : Hydrogen Storage; Metal Organic Frameworks; Adsorption; Fuel cells. Figure 1

Flow batteries for net zero in New Zealand

AbstractFlow batteries (FBs) are characterized by relatively high round trip efficiencies and benefit from high scalability. The storable energy and the power of charging and discharging the battery can be increased by increasing the size of the electrolyte storage tanks and the electrodes. Charge and discharge cycles covering many hours may be designed with flow batteries. This makes flow batteries a better choice than lithium‐ion batteries for large‐scale energy storage systems, particularly for non‐dispatchable renewable energy systems such as wind and solar, where the energy generated is highly variable and requires effective energy storage solutions. However, flow batteries also have some disadvantages, including a higher cost per unit of energy stored compared with other batteries, as well as the use of materials that in some cases are toxic, expensive, or scarce. Additionally, flow batteries cannot solve the energy storage issues over long times of a grid only supplied by non‐dispatchable electricity such as wind or solar, namely intermittency and summer to winter variability of solar, or low wind days of wind. Despite these limitations, the potential benefits of flow batteries in terms of their scalability and long cycle life, and cost‐effectiveness in case their design could be improved, making them one of the key contributors progressing towards net zero. Specifically in New Zealand, in the progress toward net‐zero the total energy supply (TES) cannot be covered by only expanding wind energy production and pumped hydro energy storage (PHES). Solar photovoltaic and likely nuclear energy supply will have to be introduced. Not all of the TES will be electrified, part of the TES will need coverage by green hydrogen fuel. Hydrogen energy storage (HES) will have to grow much more than PHES, energy storage by FBs as well as lithium‐ion batteries (LIBs) will also have to be included, given their complementarity to the other energy storage systems.

Reliability and availability modelling of a retrofitted Diesel-based cogeneration system for heat and hot water demand of an isolated Antarctic base

The reduction of greenhouse gas emissions is a relevant challenge for a sustainable development. Waste heat could be used to produce hot water by using a recovery system. This article studies the availability of a combined heat and power systems (CHP) in extreme area (Antarctic) through the integration of a waste heat recovery system with a diesel generator to produce hot water. The reliability and availability principles are incorporated to explore how the profile of hot water consumption and the hot water storage tank size affect system availability. Different combined heat and power systems are thus classified, and their availability indexes modelled by adopting the continuous Markov approach and the state space model. The results indicate that the CHP systems availability is strongly influenced by the daily hot water demand profile. As a useful recommendation, one of the considerations for increasing availability, reducing costs and greenhouse gas emissions with the CHP system is to include a hot water tank in the analysis.

The Effect of Liquid Hydrogen Tank Size on Self-Pressurization and Constant-Pressure Venting

Hydrogen represents a promising renewable fuel, and its broad application can lead to drastic reductions in greenhouse gas emissions. Keeping hydrogen in liquid form helps achieve high energy density, but also requires cryogenic conditions for storage as hydrogen evaporates at temperatures of about 20 K, which can lead to a large pressure build-up in the tank. This paper addresses the unsteady thermal modeling of cryogenic tanks with liquid hydrogen. Considering the liquid and vapor phases in the tank as two nodes with averaged properties, a lumped-element method of low computational cost is developed and used for simulating two regimes: self-pressurization (also known as autogenous pressurization, or pressure build-up in the closed tank due to external heat leaks) and constant-pressure venting (when some hydrogen is let out of the tank to maintain pressure at a fixed level). The model compares favorably (within several percent for pressure) to experimental observations for autogenous pressurization in a NASA liquid hydrogen tank. The two processes of interest in this study are numerically investigated in tanks of similar shapes but different sizes ranging from about 2 to 1200 m3. Pressure and temperature growth rates are characterized in closed tanks, where the interfacial mass transfer manifests initial condensation followed by more pronounced evaporation. In tanks where pressure is kept fixed by venting some hydrogen from the vapor domain of the tank, the initial venting rate significantly exceeds evaporation rate, but after a settling period, magnitudes of both rates approach each other and continue evolving at a slower pace. The largest tank demonstrates a six-times-lower pressure rise than the smallest tank over a 100 h period. The relative boil-off losses in continuously vented tanks are found to be approximately proportional to the inverse of the tank diameter, thus generally following simple Galilean scaling with a few percent deviation due to scale effects. The model developed in this work is flexible for analyzing a variety of processes in liquid hydrogen storage systems, raising efficiencies, which is critically important for a future economy based on renewable energy.

Spatial and Climatic Variabilities of Rainwater Tank Outcomes for an Inland City, Canberra

Most of the studies on rainwater harvesting analysis present the outcomes for particular cities, representing a single set of results for a specific city. However, in reality, significant spatial and weather variabilities may exist, due to which presenting only one set of results for a particular city would be misleading. This paper presents the potential weather and spatial variabilities on the expected water savings and supply reliability through the domestic rainwater tank for an inland city. An earlier-developed daily water balance model, eTank, was used for the calculations of annual water savings and reliability. An Australian inland city, Canberra, was selected as a case study and relevant daily rainfall data were collected from the Australian Bureau of Meteorology website. For the analysis of spatial variation, two rain gauge stations within the city of Canberra were selected. For each station, from the historical data, three years were selected as dry, average and wet years. For each weather condition, annual water savings and reliabilities were calculated for different demands with different tank sizes up to 10,000 L connected with different roof sizes. Then, variations in annual water savings and reliabilities among different weather conditions, as well as among different stations, were evaluated. It was found that, with regard to annual water savings, a maximum variation of 68.6% can be expected between dry and wet weather; however, only a 15.4% maximum spatial variation is expected among the selected stations. Regarding reliability, a maximum variation of 123% is expected between dry and wet weather. Whereas, only a 17% spatial variation is expected among the selected stations. Such a study will provide valuable insights for rainwater tank users and stakeholders on potential variabilities due to weather and spatial differences.

Hydrogen-based microgrid: Development of medium level controls in a multilevel algorithm framework

In renewable-based microgrids, intermittency caused by some energy sources highlights the important role of energy storage systems. Nowadays, hydrogen and thermal energy storage are expected to play key roles in grid-scale applications, for facilitating effective penetration of clean energy sources. This paper, through a multilevel control framework for the energy management of a renewable and reversible solid oxide based microgrid, develops medium level controls accounting for the dynamic behaviour of storage systems. The storage systems considered are a hydrogen storage tank and a thermal energy storage based on phase change material technology. In particular, the proposed algorithm is helpful in the microgrid design phase as well as for clearly assessing high-level energy management strategies, since dynamic and transient behaviours of tanks during both charging and discharging phases are validated. In this way, top-level energy management strategies can be further refined and optimized in addition to a techno-economic design being pursued, primarily through shrinking the initial sizes of storages and thereby achieving significantly lower initial capital costs. For the analyzed microgrid, its feasibility is demonstrated by reducing by as much as 40% the size of the hydrogen tank and by up to 20% the energy capacity of the thermal storage. Finally, the proposed medium level control in a multilevel algorithm framework for a hydrogen-based microgrid is also seen to be fruitful for avoiding waste energy, which can be beneficial against the background of distributed energy systems acting in virtual power plants.

Insights from the judgment bias paradigm: Social group and tank size does not affect mental state in female guppies.

Optimal holding conditions are key to animal welfare. How stressful husbandry is perceived by the animal can be determined via assessment of an animal's mental state - where it is positioned on the continuum between optimistic and pessimistic state - and can be measured using the judgment bias paradigm. In this test, individuals are trained to distinguish a rewarded from an unrewarded cue before being presented an ambiguous, intermediate cue. The response time to the ambiguous cue is then indicative of mental state. A shorter latency suggests a more positive (optimistic) mental state, a longer latency a more negative (pessimistic) mental state. Here, we used the judgment bias paradigm to assess the impact of standard laboratory housing conditions on the mental states of female guppies (Poecilia reticulata). As it is debated which holding conditions confer optimal welfare, we tested the impact of husbandry on mental state by keeping animals for three weeks in small or large social groups in either small or large tanks. We found that the different standard housing conditions we used did not lead to differences in mental state. As an unexpected side result, we found that female guppies seem lateral. Our findings of comparable mental state across housing conditions suggest that guppies either perceive the tested conditions as equally stressful or alternatively, that guppies are relatively resilient to the combination of group and tank sizes tested in this study. We conclude that the judgment bias paradigm can be a useful tool to assess fish welfare. This article is protected by copyright. All rights reserved.

Performance evaluation of an enhanced self-storing evacuated tube solar collector in residential water heating application

Phase change materials (PCMs) offer higher levels energy storage density than conventional hot water tanks commonly used with solar hot water systems. The present study aims at investigating the integration of a selected PCM within the structure of an evacuated tube solar hot water system to create some compact thermal storage capacity. Then conventional solar water heater is compared with this novel PCM-based self-storing design. The results show that the proposed self-storing design can maintain the collector output temperature at around 63 °C after 15 h of not receiving any sunlight. That is whilst the output temperature of the normal collector drops down to ambient temperature in the same period. The obtained energy storage efficiency is 57 % and 75 %, and overall thermal efficiency is 49 % and 72 %, for the normal and the self-storing collectors, respectively. For the small-scale system used in this study, the proposed design helps reduce the size of the hot water storage tank required to supply the hot water demand by 55 %. The study also shows that the same design can even yield better performance at larger scales used in practical applications.

Bubbles morphology, frequency and rising velocity in yield stress fluid under downward gas injection

Mixing in a reactor can be achieved mechanically or by the injection of a gas. This can be done by injecting a gas towards the bottom of the tank. The induced flow recirculation and then the stirring quality depends on the bubbles morphology, rising velocity and frequency detachment. This study focus on the case where the stirred fluid exhibits a yield stress. It is in line with previous studies on the gas cavity at the injection point [1], the induced flow recirculation [2] and the numerical simulation [3]. Here we quantified the bubbles diameters, aspect ratios and velocities as a function of the air flow rate, rheological parameters and tank size. Scaling laws and correlations based on the characteristic dimensionless numbers governing the flow have been proposed and validated experimentally. It was found that bubble frequencies and consequently bubble volumes and velocities are mainly governed by the balance between inertial and buoyancy forces. However, viscous and yield stress effects play an important role along buoyancy and inertial in defining the bubble aspect ratios. Weakly inertial flows are characterized by elongated bubbles while high inertial flows produce almost spherical bubbles. These experimental results are of practical interest for the design of reactor or digester where yield stress fluids have to be stirred.

Bagnold 충격수를 고려한 압축 팽창하는 갇힌 공기에 미치는 축척비 효과에 대한 상사 해석

A developed code based on the unified conservation laws of incompressible/compressible fluids is applied to analyze similarity in pressure oscillations caused by pulsating air pockets in sloshing tanks. It is shown that the nondimensional time histories of pressure show good agreements under Froude and geometric similarities, provided that there are no pulsating entrapped air pockets. However, the nondimesional period of pressure oscillation due to the pulsating air pocket becomes longer as the size of the sloshing tank increases. The discrepancy in the nondimensional period is attributed to the compressibility bias of the entrapped air. To get rid of the compressibility bias, the ullage pressure in a sloshing tank is adjusted based on the Bagnold’s impact number. The variation in the period of pressure oscillation according to the ullage pressure is explained based on the spring-mass system. It is shown that the nondimensional period of pressure oscillation is virtually constant when the ullage pressure is adjusted based on the Bagnold’s impact number, regardless of tank size. It is found that the Bagold’s impact number should be the same, if the time history of pressure is important while an entrapped air pocket pulsates.

Mechanical performance of fiber-reinforced polymer tank under road pavements for stormwater storage

Due to increasing precipitation intensity, rising sea level, and land development, urban flooding has become a major issue in many places around the world. This research aims to develop underground storage tanks (USTs) using fiber-reinforced polymer (FRP) materials for stormwater detention, storage, and reuse. The USTs are intended to be placed underneath highway or street pavements. FRP as one of the emerging structural materials possesses several advantages including high strength-to-weight ratio and corrosion resistance. The mechanical performance of USTs has rarely been visited in the literature, the majority of which focuses on leakage issues and associated environmental problems. This paper presents detailed analyses of the mechanical performance of FRP USTs, including a laboratory test on a small-scale FRP UST and a verified finite element (FE) analysis on full-scale FRP USTs. The influences of various factors on the mechanical performance of the USTs were examined, including wall thickness, water storage, interfacial roughness between FRP and soil, and tank sizes. Both results from experiments and FE studies agree satisfactorily and reveal that (i) underground FRP UST developed tensile axial strains at the top surface at the mid-span of the tank and the side surface at the mid-height; (ii) compressive axial strains developed in most of the cap region; and (iii) large compressive circumference strains developed in the FRP UST in most locations. Insights gained from the laboratory test and the FE analysis are expected to provide a general guidance on the design of FRP USTs under road pavements for urban flooding mitigation and stormwater harvesting.

A Knowledge-Based Engineering System for the Planning of Networked Rainwater Harvesting and Distribution Systems

Rainwater harvesting attracts growing interest from the field of municipal planning. When considering a rainwater harvesting system as a design object, questions include whether the system is designed for a single property or for a local water network serving multiple properties, what allows for the inclusion of buffer tanks and resource balancing among participants in the network, how to size the tanks, and how robust the system is in the face of changing demands. Knowledge-based engineering provides methods and a tool set for such planning objects. For this article, the authors applied techniques based on model-based and resource-based configuration and Bayesian decision networks to propose a knowledge-based engineering system for residential, networked rainwater harvesting and distribution systems. This enables designers to investigate the effects of different catchment areas, adjust or minimize the storage tank sizes in the grid and evaluate their effect on the individual harvest and the exchange with a central network buffer, evaluate the demands within a neighborhood based on a detailed consumer model also over time, and test the sensitivities of the single sinks and sources to the water grid. For urban planners, this offers the possibility, for example, to make design obligations for housing construction or for the refurbishment of settlements.

Comparative research on vapor injection heat pump with a novel flash tank

Two major problems for the vapor injection heat pump systems with the flash tank are the high discharge temperature and the lack of flash tank design theoretical basis, which would limit its wide application in extreme operating conditions. One possible way to overcome these problems is to effectively control the two-phase injection in the flash tank by optimizing its structure. The use of the proposed novel flash tank in the quasi-two-stage vapor injection cycle represents an economic and controllable solution. This research experimentally analyzes the influences of flash tank structure and volume on the system heating performance under different compressor frequencies and injection pressures at the ambient temperature of −10 °C. The comparative analysis is done finding that the novel flash tank could maximumly improve the system Coefficient of Performance (COPh) by 6.4% in this test, compared with the traditional type A flash tank cycle. In the meanwhile, a bad design of novel flash tank size could represent a loss of COPh improvement between 5.73% and 13.5%. Due to the particular structure, the implementation of the novel flash tank also allows the injection mass flow ratio can keep a linear relationship with the injection pressure. Moreover, the refrigerant liquid can be regularly injected into the compression chamber to control discharge temperature under 100 °C. From all the analysis, guidelines for optimizing the control strategy and the flash tank design are put forward, which can be used to perfect the real thermodynamic model of the flash tank rather than the ideal two-phase separation model.