Suction Pump Research Articles

An evaluation of patient comfort levels during expression with a modified pumping program: a prospective proof of concept study.

This study aimed to assess if the implementation of a gentle transition of vacuum mode into a breast pump suction pattern commonly used to initiate milk production would improve user comfort while expressing during the first four days postpartum. This prospective study was conducted at OLVG hospital in the Netherlands in two sequential phases. Breastfeeding patients delivering >36 weeks gestation with an infant aged ≤96 h old and a clinical indication to express milk with a breast pump were recruited. Intervention group 1 (n = 40) used a hospital-grade electric breast pump with a standard breast pump suction pattern. Intervention group 2 used a hospital-grade electric breast pump with a modified breast pump suction pattern (n = 40). The primary outcome was an objective assessment of comfort as measured by participants' need to reduce vacuum level during the 20 min test session. Secondary outcomes included the total expression volume (ml) in 20 min pumping. The study found that the primary outcome of comfort was significantly improved with the modified breast pump suction pattern compared to the standard pattern (OR 1.29, 95% CI 1.08 to 1.6) with 86% vs. 67% of participants not needing to reduce applied vacuum levels. The amount of milk expressed did not differ significantly between phases (group 1: 7.6 ml (2.7-25.5 ml), group 2: 12.0 ml (1.2-31.5 ml), p = 0.43). This study is the first to demonstrate an improvement in user comfort driven by the implementation of gentle transitions in vacuum modes in a commonly used breast pump suction pattern. Research into this novel population combining both pumping and breastfeeding in the first days after birth offers new unique insights on the requirements of breast pump suction patterns. Registered on clinical trials.gov NCT04619212. Date of registration November 6, 2020.

A novel membrane-free electrochemical separation-filtering crystallization coupling process for treating circulating cooling water

The traditional electrochemical descaling process exhibits drawbacks, including low OH− utilization efficiency, constrained cathode deposition area, and protracted homogeneous precipitation time. Consequently, this study introduces a novel membrane-free electrochemical separation-filtering crystallization (MFES-FC) coupling process to treat circulating cooling water (CCW). In the membrane-free electrochemical separation (MFES) system, OH− is rapidly extracted by pump suction from the porous cathode boundary layer solution, preventing neutralization with H+, thereby enhancing the removal of Ca2+ and Mg2+. Experimental results indicate that the pH of the pump suction water can swiftly increase from 8.13 to 11.42 within 10 min. Owing to the high supersaturation of the pump suction water, this study couples the MFES with a filtration crystallization (FC) system that employs activated carbon as the medium. This approach captures scale particles to enhance water quality and expedites the homogeneous precipitation of hardness ions, shortening the treatment time while further augmenting the removal rate. After the MFES-FC treatment, the single-pass removal rates for total hardness, Ca2+ hardness, Mg2+ hardness, and alkalinity in the effluent reached 92 %, 97 %, 64 %, and 67 %, respectively, with turbidity of 3 NTU, current efficiency of 86.6 %, and energy consumption of 7.19 kWh·kg−1 CaCO3. This coupling process facilitates an effective removal of hardness and alkalinity at a comparatively low cost, offering a new reference and inspiration for advancements in electrochemical descaling technology.

Resilience of Aboveground Biomass of Secondary Forests Following the Abandonment of Gold Mining Activity in the Southeastern Peruvian Amazon

Amazon rainforests are critical for providing a wide range of ecosystem services. In the Southeastern Peruvian Amazon; however, goldmining activities are causing severe soil degradation and forest loss. We analyzed aboveground biomass (AGB), forest structure, and species diversity recovery during secondary succession in 179 forest plots. Our study provides the first field-based quantification of AGB recovery following the abandonment by two types of goldmining (heavy machinery and suction pumping) in Madre de Dios (Peru). We found that successional secondary forests in areas subjected to suction pumping were more resilient than those in areas subjected to heavy machinery. After 20 years, mean AGB in suction pumping mining areas had reached 56% of reference forest AGB, while in areas of heavy machinery mining it was only 18%. Mining type, stand age, and distance from the forest edge had a significant effect on AGB. The influence of the distance from the forest edge on AGB varies according to mining type because the effects of species diversity on AGB are mediated by the distance from the forest edge. Our results clearly showed the dynamics of AGB recovery across a secondary succession after goldmining, and the contrasting responses of AGB between the two mining types. Our study disentangles the importance of key factors in forest recovery after mining and improves understanding of the resilience of biomass accumulation in these highly degraded ecosystems.

Glypturus ferox, a new species of ghost shrimp (Decapoda: Axiidea: Callichiridae) from the Ryukyu Islands, southwestern Japan

The callichirid ghost shrimp genus Glypturus Stimpson, 1866 was represented until now by four extant species world-wide. Only G. armatus A. Milne-Edwards, 1870 is known from the western Pacific. In this study, we describe G. ferox n. sp. based on seven specimens collected from the Ryukyu Islands, southwestern Japan. All specimens of the new species were collected in inner reef lagoons by suction pump. The new species is easily distinguished from all other congeners, including fossil taxa, by having a row of spines on the lower margin of the major cheliped palm. Molecular phylogenetic analysis using the mitochondrial 16S rRNA gene suggests that G. ferox n. sp. is sister to G. armatus; the genetic divergence between the two species is high. An identification key to extant species of Glypturus is provided. A brief overview on Japanese species of Callichiridae is also provided. Glypturus ferox n. sp. is the nineth species of the family known from Japanese waters with certainty.

Observational Analysis of Vertical Heat Flux Caused by Typhoon‐Induced Near‐Inertial Waves Under the Modulation of Mesoscale Eddies

AbstractTropical cyclones (TCs) induce heat pump and cold suction in the upper ocean layer. However, limited research investigated whether this heat can be effectively transported into the deep ocean. The present study shows that seawater at Station S2 is anomalously warmer in the deep ocean layer than at S1 and S3 during Typhoon Kalmaegi (2014) in the South China Sea. The turbulence‐induced vertical heat flux is estimated based on fine‐scale mixing parameterization but it cannot explain the warming rate below the thermocline. Therefore, a new method is proposed to estimate the vertical velocity, allowing us to calculate the heat flux more accurately. To elucidate the underlying causes of the observed differences, we analyze horizontal velocity to examine the role of mesoscale eddies in modulating near‐inertial waves (NIWs)‐induced vertical heat flux. Station S1 is located inside a cyclonic eddy while S2 and S3 are within two distinct anticyclonic eddies. According to the “Chimney Effect” theory, cyclonic (anticyclonic) eddies tend to limit (enhance) the vertical propagation of the NIWs. While this theory explains the confined heat flux at S1, it fails to explain the differences observed at S2 and S3. Further examination of the vertical structures and intensities of the two anticyclonic eddies reveals that the eddy at S2 extends much deeper and is stronger than that at S3, allowing the NIWs to propagate and transport heat deeper at S2 than at S3. The study demonstrates the role of TC‐induced NIWs in deep ocean heat transport under the influence of mesoscale eddies.

Hydroabrasive wear of jet pump nozzles

The measurements of hydroabrasive wear of the jet pumps nozzles, used on dredges operating on transferring pulp, are carried out. The measurement result is compared with the result of modelling the flow in the pump suction chamber near the nozzles. The modelling is carried out using the Fluent program complex as a part of the Ansys program; the pure water is being modelled in the suction pipe. This assumption is made taking into account that pulp contains approximately 10 percent by volume of sand, therefore the trajectories of sand particles movement coincide with the streamlines of water. The results of modeling have shown, that the angle of attack on the surface of nozzle nose part nearest to the pulpline outlet is close to zero, whereas the angles of attack on the surface of the nozzle nose part furthest from the pipeline outlet differ considerably from the zero and range from 20 to 50 degrees, that is the values at which the hydroabrasive wear increases severalfold compared to the angles close to zero. The results of modelling are confirmed by the examination of the worn nozzles. It is turned out that the nose part of the nozzles wears out along a circle unevenly, the part furthest from the pipeline outlet wears at higher rate, that leads to the bevel of the plane of the nozzle nose opening, the bevel angle reaches 20–25 degrees. The microhardness values of the nose part of the worn nozzle are also in agreement with the results of modelling. The measurements have shown, that the microhardness of the nose part of the worn nozzle is uneven along a circle, and the microhardness of the most worn side of the nozzle nose is least. This fact indicates that the different zones of the surface of the nozzle nose part differ from each other by the rigidity of stress state scheme in hydroabrasive attack. It can be used later in choosing the regime of laboratory tests on hydroabrasive wear.

Suction and discharge flow controls of a co-rotating scroll hydrogen circulation pump

The purpose of this paper is to reveal the relationship between the suction, discharge flow control and self-designed co-rotating scroll hydrogen circulation pump (CSHCP) aerodynamic performance and irreversible flow loss. The effect of five suction angles and five discharge spoiler positions on the performance and flow loss of a CSHCP was firstly revealed using the computational fluid dynamics (CFD) three-dimensional numerical simulation method combined with entropy production (EP) theory and omega vortex identification methods. The optimized suction angle and discharge spoiler position of CSHCP were identified through comparing with isentropic and volumetric efficiency, EP, vortex distribution and flow pulsation intensity. Subsequently, the performance and flow loss difference of CSHCP are further distinguished before and after optimization of suction and discharge spoiler structure under designed or variable rotational velocities. The results demonstrate that the optimized suction angle and discharge spoiler position angle are 22.5° and 45°, respectively. After the combination optimization of suction and discharge spoiler structure, the total EP and discharge temperature pulsation intensity of CSHCP are reduced by about 13.2% and 67.5% respectively. The research results provide a reference for the efficient and stable operation of HCP for fuel cell system.

IoT Based Domestic Water Supply Monitoring and Theft Identification System

Abstract: In the urban and rural areas, the water supply to the residents and commercial establishments is provided with a fixed water flow rate. Now a day’s most people’s utilize the excess water by connecting the motor pump or suction pump to suck the water directly from the area street pipeline which is considered as water theft. It causes enormous complications during summertime and also reduces their environmental resources. In this project, the proposed system is used to develop an IoT-based water supply monitoring and theft identification system by recording the flow rates at the consumer or user end. To implement the proposed water supply system, each consumer can be provided with a PIC-based microcontroller kit to record the flow rate using a flow sensor. The electrically operated solenoid valve is provided to the consumers to monitor water usage. If any excess water deduction occurs in the water supply pipeline the excess flow rate and corresponding charges will sent to the consumer ID. The valve is turned off using IoT to stop the water supply when the consumer fails to pay or uses excessive water LCD is connected with a Node MCU to display data nearby. The proposed framework is completely automated; there is no need for manpower. The domestic water supply monitoring and theft identification system offers several benefits, including improved water resource management, reduction in water wastage, and financial savings. Identifying and addressing instances of theft, it promotes fair usage and conservation of water resources, ultimately contributing to sustainability.

The Effect of Mechanical Circulatory Support on Blood Flow in the Ascending Aorta: A Combined Experimental and Computational Study.

Percutaneous mechanical circulatory support (MCS) devices are designed for short-term treatment in cases of acute decompensated heart failure as a bridge to transplant or recovery. Some of the known complications of MCS treatments are related to their hemodynamics in the aorta. The current study investigates the effect of MCS on the aortic flow. The study uses combined experimental and numerical methods to delineate complex flow structures. Particle image velocimetry (PIV) is used to capture the vortical and turbulent flow characteristics in a glass model of the human aorta. Computational fluid dynamics (CFD) analyses are used to complete the 3D flow in the aorta. Three specific MCS configurations are examined: a suction pump with a counterclockwise (CCW) rotating impeller, a suction pump with a clockwise (CW) rotating impeller, and a discharge pump with a straight jet. These models were examined under varying flow rates (1-2.5 L/min). The results show that the pump configuration strongly influences the flow in the thoracic aorta. The rotating impeller of the suction pump induces a dominant swirling flow in the aorta. The swirling flow distributes the incoming jet and reduces the turbulent intensity near the aortic valve and in the aorta. In addition, at high flow rates, the local vortices formed near the pump are washed downstream toward the aortic arch. Specifically, an MCS device with a CCW rotating impeller induces a non-physiological CCW helical flow in the descending aorta (which is opposite to the natural helical flow), while CW swirl combines better with the natural helical flow.

THE IMPACT OF TEMPERATURE ON SUCTION PERFORMANCE OF GEAR PUMPS

Through meticulous experimental setups, including a closed-loop system and precision temperature controllers, our study systematically explores the impact of temperature variations on gear pump behavior. This observed phenomenon is attributed to fluid viscosity changes and underscores the intricate interplay between thermal dynamics and gear pump efficiency. In the comparative analysis, our findings are bench-marked against industry standards, revealing both congruities and disparities. The study goes beyond the immediate implications by presenting a sensitivity analysis of different gear materials concerning temperature variations. This work not only contributes to the theoretical understanding of fluid machinery but also has practical ramifications. The presented advanced statistical insights, including a cor-relation matrix, add depth to our comprehension of the interconnected factors influencing gear pump operation. In conclusion, this study provides a nuanced understanding of temperature's influence on gear pump suction performance. By combining empirical evidence with advanced statistical insights, our findings offer practical insights for optimizing gear pump efficiency in varying temperature conditions, ultimately contributing to the evolving landscape of fluid machinery research. Keywords: gear pump, temperature variations, suction performance, fluid dynamics, experimental setup.

Study on mechanism of unsteady gas-liquid two-phase flow in liquid-ring vacuum pump

To investigate the gas-liquid two-phase flow mechanism in liquid-ring vacuum pump, the large-eddy simulation coupled with volume-of-fluid method (LES-VOF) was used to numerically simulate the unsteady gas-liquid flow characteristics in pump. The structure of gas-liquid flow within pump and its dynamic evolution characteristics were studied, and the hydraulic excitation characteristics induced by gas-liquid flow were analyzed. The result shows that the channel vortex inside the impeller on the pump suction side gradually flows out of the flow passage with the rotation of the impeller, and continuously mixes with the wake vortex at the outlet of the impeller and the separation vortex at the inner wall of the casing. The evolution and development of vortex structures with different intensities and scales near the inner wall of the suction side casing have a relatively large contribution to pressure fluctuation. The wake vortex at the impeller outlet of the exhaust side gradually enters the flow passage and dissipates gradually with time. There is an obvious high-intensity backflow vortex in the exhaust section due to the pressure difference between the flow channels near the leading edge of the exhaust port, which leads to obvious rotor-stator interaction in the exhaust section.

The Investigation of the Response Mechanism of SST and Chlorophyll to Super Typhoon “Rey” in the South China Sea

As one of the most significant disturbance sources in the upper marine environment of the South China Sea, tropical cyclones (typhoons) serve as a typical research subject for investigating the energy transfer process between the ocean and atmosphere. Utilizing satellite remote sensing data and focusing on Typhoon Rey No. 22’s transit event in 2021, this study quantitatively analyzes typhoon-induced energy input through heat pumping and cold suction at both surface and subsurface levels of the ocean. Additionally, it explores the response characteristics and feedback mechanisms of sea surface temperature (SST) and chlorophyll-a concentration (Chl-a) in the South China Sea to typhoon events. The research results show that the SST variation along the typhoon track displayed an asymmetric pattern, with a more pronounced warming on the right side and a cold anomaly lasting for 3–5 days on the left side. The subsurface warm anomaly dominated on the right side, showing a maximum temperature difference of 1.54 °C, whereas Ekman suction-induced upwelling led to cooling effects both at the subsurface and surface level on the left side, resulting in a maximum temperature difference of −3.28 °C. During the typhoon event, there was a significant decrease in sea surface heat flux, reaching 323.36 W/m2, accompanied by corresponding changes in SST due to processes such as upwelling, seawater mixing, and air–sea heat transfer dynamics where anomalies arising from oceanic dynamic processes and exchange through sea surface heat flux contributed equally. Furthermore, strong suction-induced upwelling during the typhoon influenced chlorophyll concentration within the central and western regions of the South China Sea (13.5° N–16.5° N, 111° E–112.5° E), resulting in significant enhancement and reaching its peak value at approximately 0.65 mg/L. The average chlorophyll concentration increased by approximately 0.31 mg/L.

The influence of ring clearance on the performance of a double-suction centrifugal pump

Due to the complex structure of a double-suction pump's suction chamber, the flow in the pump's cavity is often ignored in numerical simulations because of difficulties in structured hexahedral meshing. However, the wear ring clearance interlinking the pump chamber leads the fluid at the impeller inlet directly to the impeller area. This significantly impacts the pump's internal flow field, so the influence of the clearance on the internal flow of a double-suction pump cannot be ignored. This paper develops four three-dimensional double-suction pump models with different wear ring clearances to investigate their influence on pump performance, and structured hexahedral meshes were used for all the computational domains. The clearances varied from 0.2 to 0.5 mm in 0.1 mm increments. The influences of the clearance on the energy loss, external characteristics, and internal flow field distribution of the pump were simulated via a verified computational fluid dynamics method. The results show that the wear ring leakage decreases with the flow rate and increases with wear ring clearance. The increase in backflow leads to an internal flow disorder inside the impeller, resulting in a decreased head and efficiency. Energy loss is mainly caused by increasing the turbulence entropy production with an increasing wear ring clearance. Also, the low-pressure region in the pump cavity expands to the volute with increasing clearance, and the impeller outlet pressure decreases. This study's research on wear ring clearance provides a reference for the design and application of double-suction centrifugal pumps.

Visual experimental study on cavitation performance of double-suction centrifugal pump

In this paper, the cavitation test results of double-suction centrifugal pump are further “visualized” and verified by using high-speed photography technology to photograph the development process and flow field of impeller inlet cavitation. By optimizing the impeller inlet parameters, the key geometric factors affecting the cavitation performance of the double suction pump were determined. The experimental results show that by optimizing the inlet parameters of the double-suction pump and combining the visualization test verification of cavitation, on the basis of ensuring the wide and efficient efficiency of the double-suction centrifugal pump, the optimization scheme of the experimental design greatly improves its cavitation performance, and provides a new design idea and reference for guiding the development and design of products with high cavitation performance.

Intraoperative Extracorporeal Support during Lung Transplantation: Not Just for the High-Risk Patient.

The use of intraoperative mechanical support during lung transplantation has traditionally been a controversial topic. Trends for intraoperative mechanical support strategies swing like a pendulum. Historically, cardiopulmonary bypass (CPB) was the modality of choice during transplantation. It provides full hemodynamic support including oxygenation and decarboxylation. Surgical exposure is improved by permitting the drainage of the heart and provides more permissive retraction. CPBs contain drainage reservoirs with hand-held pump suction catheters promoting blood conservation through collection and re-circulation. But CPB has its disadvantages. It is known to cause systemic inflammation and coagulopathy. CPB requires high doses of heparinization, which increases bleeding risks. As transplantation progressed, off-pump transplantation began to trend as a preferable option. ECMO, however, has many of the benefits of CPB with less of the risk. Outcomes were improved with ECMO compared to CPB. CPB has a higher blood transfusion requirement, a higher need for post-operative ECMO support, a higher re-intubation rate, high rates of kidney injury and need for hemodialysis, longer ICU stays, higher incidences of PGD grade 3, as well as overall in-hospital mortality when compared with ECMO use. The focus now shifts to using intraoperative mechanical support to protect the graft, helping to reduce ischemia-reperfusion injury and allowing for lung protective ventilator settings. Studies show that the routine use of ECMO during transplantation decreases the rate of primary graft dysfunction and many adverse outcomes including ventilator time, need for tracheostomy, renal failure, post-operative ECMO requirements, and others. As intraoperative planned ECMO is considered a safe and effective approach, with improved survival and better overall outcomes compared to both unplanned ECMO implementation and off-pump transplantation, its routine use should be taken into consideration as standard protocol.

Fluid analysis of the cavitation of the microsegment gear pump operating at high-pressure condition

To investigate the cavitation of the microsegment gear pump and its effect on the performance of the gear pump, the gear equations of the microsegment gear for the pump were given, the cavitation mechanism was described, and the dynamic cavitation model was derived. The fluid analysis of the microsegment gear pump was carried out using the computational fluid dynamics software (Fluent), and the evolution of cavitation and its effect on the outlet flow characteristics were investigated. The results show that: the vortex occurred at the back edge of the microsegment gear pump suction chamber teeth and the top of the teeth, thus producing cavitation; the cavitation presented periodic formation-development-disappearance of the process; cavitation led to increased outlet flow fluctuations and pressure pulsations, and also led to a decrease in the average value of outlet flow and average value of outlet pressure. The periodic cavitation led to the periodic fluctuation in outlet flow and pressure. At the same time, cavitation also caused a decrease in the total head of the microsegment gear pump. Cavitation in the microsegment gear pump increased with increasing the speed and decreasing the suction pressure.

Multi-objective optimization of concrete pumping S-pipe based on DEM and NSGA-II algorithm

In the process of fresh concrete pumping, the S-pipe plays a crucial role in the pumping system. The impact and scratching of concrete aggregate on the wall of S-pipe will cause the wear of the wall and lessen its service life. The structural design of the pumping S-pipe typically relies on experience, and the cost for experiments is too expensive. In addition, the influence mechanism of structural parameters on S-pipe wear is still unclear. In view of this, to reduce the wear of S-pipe and investigate the influence of structural parameters on the wear of S-pipe, the structural parameters of S-pipe (curvature radius r1 and r2, horizontal dimension l3, and inclination angle θ) were optimised through discrete element numerical simulation combined with the non-dominated sorting genetic algorithm-II (NSGA-II) in this paper. Firstly, the wear coefficient was determined by friction and wear test. The discrete element method (DEM) model of pumping suction unit was simplified, and the S-pipe was parameterised. Secondly, sample points and their exact values of the optimization objectives were obtained by Latin hypercube sampling (LHS) plan and DEM simulations, respectively. From these, a Kriging surrogate model was constructed. Taking the average wear rate and the maximum wear of the S-pipe as the optimization objectives, a multi-objective optimization design was performed based on the NSGA-II and the Kriging models. After optimization, a series of Pareto optimal S-pipe models were obtained. Comparing the optimised model with the original model, the average wear rate and maximum wear amount of the S-pipe were reduced by 9% and 26%, respectively.

Retrieving A retained Heavy Silicone Oil Bubble: Two Novel Surgical Techniques.

To describe two surgical techniques for rescuing a retained heavy silicone oil bubble in the posterior pole: 1) light pipe method and 2) perfluorocarbon liquid method. The surgical techniques are described in detail, along with an illustrative video for each. A short 25-gauge metallic cannula and active suction pump are used for standard heavy silicone oil removal. Both surgical approaches are practical and effective options to complete the removal of heavy silicone oil when a bubble sinks to the posterior pole. Both the light pipe and perfluorocarbon methods are suitable to remove retained heavy silicone oil and thus avoid the need for further incisions and the risks associated with the use of larger gauge instrumentation.

Effects of saline nebulization on SARS-CoV-2 RNA spreading and exhaled bio-aerosol particles in COVID-19 patients

Nebulised therapy is the mainstay for treating obstructive airway diseases, but there is heightened concern about the potential risk for SARS-CoV-2 transmission during nebulisation in COVID-19 patients. We investigated the effects of 0.9% saline nebulisation on SARS-CoV-2 RNA spreading in 11 COVID-19 patients (5 females, mean age 62.45±9.31 yr). In 6 out of the 11 patients we also ascertained whether saline nebulisation changed the number of exhaled bioaeroosl particles. Air samples were collected using suction pumps equipped with 0.45μm PTFE filters and positioned around the patient's bed. Exhaled particles were quantified by using an optical particle counter. At baseline (i.e. before nebulisation) SARS-CoV-2 was detected more frequently in the pumps close to the patient than in those far away. After saline nebulisation, the detection of SARS-CoV-2 in the pumps close to the patient was comparable to that observed at baseline. In the pumps far from the patient, saline nebulisation slightly, but not significantly, increased SARS-CoV-2 RNA detection compared to baseline. Overall, no significant changes in the SARS-CoV-2 RNA detection were observed after saline nebulisation. At baseline, exhaled particles emission varied among patients, with two of them showing higher emission of particles than the remaining patients. Saline nebulisation induced a marked decrease in exhaled particles in the 2 patients who displayed high emission at baseline, whereas no changes were observed in the remaining patients. Saline nebulisation did not significantly change SARS-CoV-2 RNA spreading. Thus, there is no compelling reason to alter aerosol delivery devices for patients with established nebuliser-based regimens.

Quasi One-Dimensional characteristic analysis of ejector nozzle for turbofan propulsion system

To investigate the impact of the ejector characteristics of the exhaust system on the overall performance of a turbofan engine, this paper presents a study on the overall performance of the turbofan engine equipped with an ejector nozzle, focusing on its characteristics. Firstly, the design of the ejector exhaust system is presented and its ejector characteristics are analyzed through two-dimensional computational fluid dynamics simulations. Subsequently, a one-dimensional theoretical analysis of the ejector is conducted, and the pump suction and ejector nozzle’s thrust characteristics are determined based on the analysis results. Furthermore, a two-dimensional interpolation method is proposed to calculate the ejector coefficient, which utilizes the ejector's pump suction characteristics. By applying the matching principle of the ejector coefficient, a component-level model of the turbofan engine with an ejector nozzle is established. Based on this model, a method for predicting the backward infrared radiation intensity of the ejector exhaust system is proposed to investigate the influence of the ejector nozzle characteristics on the overall engine performance and infrared signature. The results demonstrate that the installation of the ejector exhaust system leads to a slight decrease in the overall engine performance, in which the average decrease of thrust is about 1.5%, and the average increase in fuel consumption is about 0.5%.but significantly reduces the infrared stealth characteristics, the average reduction is about 20%, which has good infrared stealth effect.