Lower Head Research Articles

Uncertainty and sensitivity analysis of the ASTEC simulations results of a MBLOCA scenario in a generic KONVOI plant using the FSTC tool

This paper presents the results of uncertainty and sensitivity (U&S) analysis of Medium Break Loss-of-Coolant (MBLOCA) severe accident (SA) scenario simulations performed with the ASTEC code with a generic input deck prepared for a KONVOI-1300 nuclear power plant (NPP). The analysis was done with the in-house Fast Source Term Calculation Tool (FSTC) (currently: KArlsruhe Tool for Uncertainty and Sensitivity Analysis (KATUSA)). Part of the presented here results – analysis of MBLOCA scenario simulations up to the basemat rupture - were already shown at the ERMSAR conference in 2022. Here an extension related to the analysis of shorter MBLOCA simulations (up to 6000 s after lower head vessel failure (LHVF)) and investigation of the influence from adding correlations between uncertain input parameters is given. The analysis allows to identify which uncertain input parameters influence the release of fission products (FPs) in the containment and environment at the different stages of SA progression.

The influence of midsole horizontal and vertical deformation on soft tissue vibrations and bone acceleration during running

ABSTRACT Increased midsole deformation can limit exposure to high impact and vibration magnitudes while running. The aim of this study was to evaluate the effect of shoes eliciting different midsole deformation on ground reaction forces, heel impact, soft tissue vibrations and bone vibrations. Forty-eight runners performed a 5-min running task on an instrumented treadmill at a self-selected pace with four different shoes. Midsole horizontal and vertical deformations were quantified with relative displacement of seven reflective markers placed on the midsole of the shoe and tracked by eight optoelectronic cameras. Heel impacts, soft tissue and bone vibrations of lower leg muscle groups, sacrum and head were quantified with tri-axial accelerometers. Continuous wavelet transform was used to assess magnitude and frequency of the acceleration data. Linear mixed models and non-parametric one-dimensional regressions between the accelerometer data and shoe deformation were performed. Greater horizontal and vertical deformations decreased the magnitude (up to 4.6% per mm) and frequency (up to 0.6 Hz per mm) of soft tissue vibrations and bone accelerations. Accelerations of the heel, tibia, gastrocnemius medialis and vastus lateralis were more influenced than the sacrum and head. Increasing midsole deformation could therefore mitigate the risk of injury, while increasing running comfort and smoothness.

Assessment of Low Head Irrigation Systems and Soil Mulching to Save Water for maize Cultivation

Assessment of Low Head Irrigation Systems and Soil Mulching to Save Water for maize Cultivation

Effects of Unsaturated Flow on Salt Distributions in Tidally Influenced Coastal Unconfined Aquifers

AbstractUnsaturated flow influences both the seawater extent under steady‐state conditions and the propagation of tides in coastal aquifers. However, its effects on salt distributions in tidally influenced coastal aquifers are little investigated. The present study used numerical simulations and data from laboratory experiments to analyze the effects of unsaturated flow on density‐dependent solute transport in coastal unconfined aquifers. The effects of the inland boundary condition (i.e., constant‐head or constant‐flux) were tested. Compared to a stable sea level, the results show that unsaturated flow has a more pronounced influence on salt distributions in coastal unconfined aquifers when tides are considered, regardless of the type of inland boundary condition. Neglect of unsaturated flow effects leads to expansion of the upper saline plume (USP), shrinkage of the saltwater wedge (seaward movement of saltwater wedge), and overestimation of water and salt exchange across the aquifer‐ocean interface. This is caused by a lower head in the nearshore area during high‐tide periods with the unsaturated zone effects removed. Thus, without the unsaturated zone, stronger head gradients within the nearshore aquifer occur at high tide, leading to stronger tidally driven seawater infiltration and hence a larger USP. Counterintuitively, ignoring unsaturated flow effects leads to greater average inland head over a tidal period, which shifts the saltwater wedge seaward. It is concluded that unsaturated zone effects should not be neglected for modeling tide‐affected seawater intrusion, especially if quantification of near‐shore conditions is important.

Suicide and depression in former contact sports participants: population-based cohort study, systematic review, and meta-analysis.

Former participants in sports characterised by low intensity repetitive head impact appear to have elevated rates of later dementia, but links with other psychological health outcomes such as depression and suicide are uncertain. We quantified the occurrence of these endpoints in former contact sports athletes against general population controls using new data from a cohort study and a meta-analysis. The cohort study comprised 2004 retired male athletes, who had competed internationally as amateurs for Finland across a range of sports, and 1385 general population controls. All study members were linked to mortality and hospitalisation registries. In the PROSPERO-registered systematic review (CRD42022352780), we searched PubMed and Embase to October 31 2022 for cohort studies that reported standard estimates of association and precision. Study-specific estimates were aggregated in a random-effect meta-analysis. The Newcastle-Ottawa Scale was used to appraise the quality of each study. In survival analyses of the Finnish cohort data, former boxers (depression: hazard ratio 1.43 [95% CI 0.73, 2.78]; suicide: 1.75 [0.64, 4.38]), Olympic-style wrestlers (depression: 0.94 [0.44, 2.00]; suicide: 1.60 [0.64, 3.99]), and soccer players (depression: 0.62 [0.26, 1.48]; suicide: 0.50 [0.11, 2.16]) did not have statistically higher rates of major depressive disorder or suicide at follow-up relative to controls. In the systematic review, 7 cohort studies met inclusion criteria. After aggregating results with the Finnish cohort, retired soccer players appeared to have a lower risk of depression (summary risk ratio: 0.71 [0.54, 0.93]) relative to general population controls, while the rate of suicide was statistically the same across groups (0.70 [0.40, 1.23]). Past participation in American football seemed to be associated with some protection against suicide (0.58 [0.43, 0.80]) but there were insufficient studies of depression in this sport to facilitate aggregation. The aggregation of results from the soccer and American football studies showed directionally consistent relationships and there was no indication of inter-study heterogeneity (I2=0%). Based on a small cluster of studies exclusively comprising men, retired soccer players had a lower rate of later depression and former American football players had a lower risk of suicide relative to comparator groups. Whether these findings are generalisable to women requires testing. The preparation of this manuscript was unfunded.

Axial water jet injection in a low head Francis turbine at part load

The part load operation of a Francis turbine generally develops a rotating vortex rope (RVR) in the draft tube, generating flow instabilities and pressure pulsations. The present work reports the axial water injection method to mitigate the RVR and its associated pulsations in the draft tube. The runner cone is modified to install a nozzle of three different designs for water jet injection. Water is injected axially at the rate of 0.5% to 2% of the main flow. Spectral analysis is performed to assess the pressure amplitude and dominating frequency affected by the water injection. Spectrogram and spatial harmonic decomposition show a reduction in synchronous and asynchronous pulsation amplitudes. The pressure recovery in the draft tube cone is also improved. The spectral analysis shows that the water injection at 1% and 1.25% is the most effective. The water injection above 1.25% to 2% causes pulsations near the draft tube bend as the water jet bounces back after striking the elbow. A sharp decrease in the Strouhal frequency is observed above 0.5% jet injection. The efficiency of the turbine is also improved by water jet injection.

A short session of maternal hyperoxygenation ameliorates the cerebral oxygenation difference between fetuses with and without congenital heart defects

ObjectivesTo assess if a 10 min session of maternal hyperoxygenation increases cerebral tissue oxygenation as measured by magnetic resonance imaging (MRI) T2* in fetuses with and without congenital heart defects (CHDs). Study designAt mean gestational ages of 32 (early) and 37 (late), we measured fetal cerebral T2* before and during the last minutes of a 10 min maternal hyperoxygenation (oxygen 10 l/min, Hudson non-rebreathing mask) in 22 fetuses without CHDs and 11 fetuses with CHDs using a 1.5 Tesla Philips scanner with a breath-hold, multi-echo, gradient-echo sequence. ResultsDuring maternal hyperoxygenation equilibrium, the mean fetal cerebral T2* values in CHD fetuses seemingly normalized and were comparable to those in fetuses without CHD breathing ambient air. Hyperoxygenation T2* was 160 ms (CI 149–170) early and 123 ms (CI 112–134) late in fetuses with CHD and ambient air T2* was 158 ms (CI 152 to 164) early and 126 ms (CI 120–131) late in fetuses without CHD, (p=0.97). Lower ambient air cerebral T2* z-score at the late-stage scan was correlated with lower head circumference z-scores at birth. ConclusionOur findings suggest that fetal cerebral oxygenation in CHD fetuses can reach normal values during a short session of maternal hyperoxygenation. This supports the hypothesis that tissue hypoxia can influence brain development in fetuses with CHD. However, since side effects of fetal hyperoxygenation have been described, it remains to be determined if chronic maternal hyperoxygenation has a positive impact on the fetal brain in CHDs.

Deterioration of brachycephalic obstructive airway syndrome in a French bulldog following surgical stabilisation of atlantoaxial subluxation with concurrent atlas malformation

AbstractA 2‐year 10‐month‐old French bulldog presented with a history of intermittent yelping episodes and low head carriage. Examination revealed cervical hyperaesthesia and grade I brachycephalic obstructive airway syndrome. Magnetic resonance imaging and computed tomography of the cervical vertebral column demonstrated a malformation of the atlas and atlantoaxial subluxation causing spinal cord compression. Ventral atlantoaxial stabilisation was performed, aided by three‐dimensional printed, patient‐specific drill guides, bicortical bone screws and polymethylmethacrylate. Four months later, the patient re‐presented being pain free but for deterioration of upper respiratory noise, distress and exercise intolerance. Grade III brachycephalic obstructive airway syndrome was evident on examination. Assessment of the post‐stabilisation computed tomography images and recent radiographs suggested that the rapid progression of brachycephalic obstructive airway syndrome had been caused by the stabilisation construct causing further narrowing of the nasopharynx by ventral and rostral displacement of the dorsocaudal nasopharyngeal wall. A folded flap palatoplasty was performed leading to excellent short‐ and long‐term outcome.

Surgical Outcome and Treatment Trends in 1289 Infants with Micrognathia: A Multicenter Cohort.

Studies of infants with micrognathia, especially Robin sequence, are limited by its rarity and both phenotypic and diagnostic variability. Most knowledge of this condition is sourced from small, single-institution samples. This is a cross-sectional study including infants with micrognathia admitted to 38 Children's Hospital Neonatal Consortium centers from 2010 through 2020. Predictor variables included demographic data, birth characteristics, cleft, and syndrome status. Outcome variables included length of stay, death, feeding or respiratory support, and secondary airway operations. A total of 1289 infants with micrognathia had surgery to correct upper airway obstruction. Mean age and weight at operation were 34.8 ± 1.8 weeks and 3515.4 ± 42 g, respectively. A syndromic diagnosis was made in 150 (11.6%) patients, with Stickler (5.4%) and Treacher Collins (2.2%) syndromes being the most common. Operations included mandibular distraction osteogenesis (MDO) in 66.3%, tracheostomy in 25.4%, and tongue-lip adhesion (TLA) in 8.3%. Patients receiving a tracheostomy had lower birthweight, head circumference, gestational age, and Apgar scores. Patients undergoing MDO were less likely to need a second airway operation compared with patients undergoing TLA (3.5% versus 17.8%; P < 0.001). The proportion of infants feeding exclusively orally at hospital discharge differed significantly, from most to least: MDO, TLA, and tracheostomy. Hospital length of stay was not statistically different for patients who had MDO or TLA, but was longer for those with primary tracheostomy. The mortality rate was low for all operations (0.5%). In this surgical patient cohort, MDO was associated with shorter hospital stay, improved oral feeding, and lower rates of secondary airway operations. Prospective multicenter studies are necessary to support these conclusions. Risk, III.

Exact simulation of the groundwater flow in anisotropic confined aquifer near time-varying streams by comprehensive new analytical solutions

This paper presents some new analytical solutions to an accurate prediction of the behavior of the groundwater flow in aquifers in response to changes in surface water. The new analytical solutions are obtained using integral transforms. An anisotropic rectangular confined aquifer bounded with four time-varying streams is undertaken. The effects of anisotropy on groundwater head and flow rate near time-varying streams are investigated. Depending on the change rates of the streams level, an anisotropic aquifer may render either lower or higher hydraulic head than an isotropic aquifer. In addition, an anisotropic aquifer has provided less water exchange at the interfaces than an isotropic one. The sensitivity of the hydraulic head to change rate of the streams level in both isotropic and anisotropic aquifers is evaluated. It is shown that the aquifer response is more sensitive to change rate of the streams parallel to y-direction and less sensitive to change rate of the streams parallel to x-direction in an anisotropic aquifer and vice versa in an isotropic aquifer. The results of the present new analytical solutions are compared with numerical model of MODFLOW. The results obtained from the presented solutions showed good agreement with the results of MODFLOW. The results show that the presented new analytical solutions are accurate, robust and efficient. Therefore, the results indicate that the presented new analytical solutions are very effective in the simulation of the groundwater flow in river–aquifer systems. Furthermore, one of the advantages of the new analytical solutions is to investigate the sensitivity analysis of aquifer parameters, which has been carried out in this paper. Also, some other new analytical solutions for steady-state conditions and sudden fall in streams level are provided as well. Feasibility of the proposed new analytical solutions is presented via calculating and simulating the hydraulics of groundwater flow in river–aquifer systems by means of integral transforms.

Study on the lower head failure in severe accident Part I: Model development and validation

Under the in-vessel retention (IVR) scenario, the lower head is loaded by the deadweight of melt and the vessel, the internal pressure, and the temperature field. This thermal–mechanical load will destroy the integrity of the reactor pressure vessel (RPV). The failure of the lower head indicates that the in-vessel accident progression has entered the final stage. If the failure occurs, its location and time have to be evaluated. However, most severe accident analysis codes judge RPV failures based on simple parametric models, which cannot accurately predict the failure time, modes, and locations. In this paper, the Lower Head Thermal-Mechanical Behavior analysis module (LHTMB) and Large Displacement model are developed with reference to the generalized Hooke’s law and the Large Displacement elastic–plastic theoretical model. The failure of the lower head is judged by several failure criteria. The developed failure model of lower head is verified based on the OLHF-1 numerical simulation results and experimental data. The mechanical results show that creep rate is usually highest at the location where the lower head is most prone to failure. Comparison of various failure criteria shows that RPV failure can be determined with high confidence when Larson–Miller life fraction and Hedl-Dorn parameter criteria are satisfied.

Ultrasonographic evaluation of infant hips in the Pavlik harness compared to body-worn commercial baby carriers.

While many factors contribute to development and subsequent correction of developmental hip dysplasia (DDH) in infants, hip positioning and muscle activity play a significant role. Lower-limb restrictive extension positions, such as with swaddling, are detrimental for hip development, and some baby gear leads to reduced lower limb muscle activity. Yet how baby gear impacts hip position during wear remains unclear. The purpose of this study was to compare the Graf's alpha angle and femoral head coverage of healthy infants and infants with mild DDH (instability) in the Pavlik harness and baby carriers. We obtained coronal hip ultrasound images of 10 healthy full-term infants (13.5 ± 3.4 weeks, 5F/5M) and three full-term mild DDH infants (8.9 ± 4.0 weeks, 2F/1M) in three conditions: Pavlik harness, wide-base baby carrier, and narrow-base baby carrier. Repeated measures analysis of variance was used to compare Graf's alpha angles and femoral head coverages across the conditions (p < 0.05), with post hoc pairwise tests (p < 0.0167). The Graf's alpha angle in the narrow-base carrier was 6.9° lower than the Pavlik harness, while the wide-base carrier was not different. Femoral head coverage was 10%-12% lower for the narrow-base carrier. The three mild DDH infants exhibited lower Graf's alpha angles and femoral head coverage in all measurements, with the Graf's alpha angle in the narrow-base carrier measuring 49.0°. This research demonstrated that wide-base baby carriers held hips in a position that was not significantly different from the Pavlik harness, meaning that babywearing in a wide-base carrier may have benefits for healthy hip development.

Investigating the hydraulic performance of slanted axial flow pumps using an enstrophy dissipation-based hybrid optimization approach

Axial flow pumps (AFPs) are widely employed in urban flood control and drainage systems due to its high discharge at relatively low heads. As off-design condition becomes more common in real operations, we proposed an enstrophy dissipation-based hybrid optimization (EDHO) approach, which combines both the advantage of sparrow search algorithm and Non-dominated Sorting Genetic Algorithm III (NSGA-ΙΙΙ) to enlarge the Preferred Operating Range (POR) of a slanted axial flow pump (SAFP). The overall hydraulic performance was optimized with the proposed EDHO approach with a special focus on energy loss mechanism. According to the analysis, eddy dissipation occupied the most energy loss under partial loads, while shear dissipation also contributed a lot under overload conditions especially around impellers. It is demonstrated that the POR of SAFP was significantly improved after optimization. In particular, the available operation interval was broadened, and the corresponding head and efficiency were remarkably increased by refining the impeller and diffuser profiles. In contrast with NSGA-II, NSGA-III, and multi-objective evolutionary algorithm, the novel hybrid algorithm showed significantly better convergence performance, solution diversity, and stability.

Lower Head Water Turbine

Abstract: Increase in human population increases the need for energy. Sustainable energy production is gaining importance day by day. At the same time rapid urbanization and industrialization combined with improper town planning has led to the destruction and death of nearby water bodies. Discharge of drainage water without aeration or any other treatment in Metropolitan Indian cities such as Delhi, Mumbai, Nashik and all others have to led to the blackening of water sources. Indian city drains handle sheer volumes of water every day. A new method of aerating water combined with power generation could go a long way in solving the problem of water treatment as well as power generation. Even under low head this much amount of water if efficiently utilized can generate sufficient power not only for the plant but also for the grid. By using the power of water in vortex flow under gravity, an attempt is made to make power from Indian drains. To generate electricity, water must be in motion. This is kinetic (moving) energy. When flowing water turns blades in a turbine, the form is changed to mechanical energy. The vortex is a form of kinetic energy storage by which water under motion is trapped in a dynamic way. This increased amount of kinetic energy that gets trapped inside a vortex boosts the power inside a vortex.

Interference effects on the processing of Korean double relative clauses

The current investigates the parsing process and its utilization of various linguistic information to resolve dependencies in Korean double relative clauses. While previous research has revealed evidence of interference effects of a distractor during dependency formations, a distractor involving dependency formations by itself has not been thoroughly explored. In light of this, we aimed to explore how the grammatical-role parallelism of a distractor modulates multiple filler-gap dependencies and examine the role of case marking in the resolution of these dependencies. In a self-paced reading experiment, we discovered that the parallelism effects of both head nouns were instrumental in the resolution of longer dependencies of a higher head noun and its gap. The non-parallel role of a distractor (i.e., low head noun) was reanalyzed before the integration of higher head noun and its gap. This finding suggests that parallelism effects play a critical role in the resolution of complex dependency structures. Additionally, our experiments investigated the role of case marking as a morphosyntactic cue in predicting the syntactic encoding of upcoming noun phrases. Our results demonstrated the immediate processing difficulty of conditions with double nominative markers, suggesting that parsers are selectively sensitive to case marking. Overall, our study contributes to our understanding of the parsing process and the selective use of linguistic cues in the resolution of complex dependency structures.

Botulinum toxin type A infiltration in spasticity and cervical dystonia. Muscle morphology: an overlooked factor

IntroductionBotulinum toxin type A is used to treat spasticity and dystonia. However, its relationship with muscle morphology has not been studied. The action mechanism of botulinum toxin is based on the inhibition of acetylcholine release. Therefore, larger doses of toxin would be needed to treat larger muscles. This study aims to establish whether there is a discrepancy between muscle morphology and the botulinum toxin doses administered. MethodsWe dissected, and subsequently measured and weighed, muscles from the upper and lower limbs and the head of a fresh cadaver. We consulted the summary of product characteristics for botulinum toxin type A to establish the recommended doses for each muscle and calculated the number of units infiltrated per gramme of muscle. ResultsDifferent muscles present considerable morphological variability, and the doses of botulinum toxin administered to each muscle are very similar. We observed great variability in the amount of botulinum toxin administered per gramme of muscle, ranging from 0.3 U/g in the biceps femoris to 14.6 U/g in the scalene muscles. The mean dose was 2.55 U/g. The doses administered for nearly all lower limb muscles were below this value. ConclusionsThere are significant differences in morphology between the muscles of the lower limbs, upper limbs, and head, but similar doses of botulinum toxin are administered to each muscle. These differences result in great variability in the number of units of botulinum toxin administered per gramme of muscle.

Free-Surface Vortices Mitigation using Anti-Vortex Plates in Dam Intakes through CFD

By recording parameters such as velocity and volume fraction by contour plots or plane, a CFD model enables to analyse flow patterns in the model, such as free-surface vortices A free-surface vortex, a common problem may indeed be observed in a variety of submerged water intakes, notably shallow basins and low head intakes. These FSVs are likely to form an air-core vortex, eventually entrapping detritus and air pockets in the water intake system and causing further vibration and damage to the downstream turbine. When paired with a high velocity, the formation of vortices in the system been known to produce hydraulic transients, which cause unwanted operation or pressure changes. The model of the 1:100 scale dam reservoir was generated, computationally meshed, and modelled in FLUENT under ANSYS 2019 R3 at two different water levels to observe the FSV formations. To mitigate those FSV formations, anti-vortex plates with two distinct plates—square and wedge—were used. From the findings square plates outperform wedge plates because square it lowers the speed of a fast-flowing fluid and reduces it into a laminar flow rather of a turbulent flow, which benefits vortex class deterioration. Data from the simulation and experimental shows a strong agreement in terms of velocity at outlet 1 from both water levels with relative errors of 3.0% and 14.1% respectively

GROUNDWATER FLOW DIRECTION EVALUATION FOR FLOOD AND CONTAMINATION CONTROL IN OSUBI, SOUTHERN NIGERIA

The determination of groundwater flow direction is essential in flood and groundwater contamination control. This study aimed at determining the groundwater flow direction in the study area to infer possible areas of further spread of contaminants and identify areas that might be prone to flooding shortly. Fifty (50) hand-dug wells were sampled with the aid of a long tape (200/60m) and a global positioning system (GPS) to determine their hydraulic heads, while topography and groundwater flow direction maps of the study area were generated using surfer 13 and groundwater modeling software, respectively. The result revealed that the hydraulic heads and static water level (SWL) values range from 0.63-27.15 m and 1.15–4.88 m, respectively, while the elevation values range from 5–30 m. The study area is characterized by undulating and relatively flat terrain in different parts of the area, while the groundwater flow direction depicts a non-uniform directional flow of groundwater in the study area. This suggests that the groundwater contamination discovered in the area might soon spread to contaminate their nearby environs if not promptly and urgently controlled. It is hereby recommended that every anthropogenic activity, such as abattoirs, mechanic workshops, dumpsites, etc., that can increase the rate of groundwater contamination in the study area be restricted to the north-eastern, eastern, and southeastern parts due to their low hydraulic heads.

A scoping study on remelting process of a debris bed in the lower head of reactor pressure vessel

Coolability and retention of core melt (corium) in the lower head of reactor pressure vessel (RPV) has been accepted as a severe accident management strategy to maintain the reactor pressure vessel (RPV) integrity of a light water reactor. To qualify the in-vessel melt retention strategy, lots of studies have been performed to investigate the natural convection heat transfer of a melt pool in the lower head. However, little work has been attributed to the precursory phase of the melt pool, i.e., the remelting process of a debris bed which is formed in the lower head at the very beginning of corium relocation from the core the lower head. The present study is motivated to conduct an experimental study on the debris remelting process. For this purpose, a dedicated test facility named COREM (COrium REMelting) is conceived and constructed, which features internal heating of electromagnetic induction and visualization of debris remelting dynamics. The test section is a semicircular vessel representing a slice of scaled-down RPV lower head, whose front and back walls are made of transparent tempered glass which facilitate visualization and induction heating of the debris bed. Fiber probes with multiple optical temperature sensors are mounted in the semicircular wall of the test section to measure its temperature distribution. In the scoping test, n-octanol and Wood's metal are selected as the simulant materials of metallic and oxidic components of corium, respectively, and their particles ware loaded in the test section to form a debris bed. This paper presents the first two scoping tests which have been performed with the COREM facility so far, under different mixing ratios of two debris materials. The measured data include the photography of debris remelting processes and the temperatures in the debris bed and the semicircular wall. Based on the temperature distributions, heat flux profile along the semicircular vessel wall is also estimated. The scoping tests well reproduce the dynamic process of debris remelting, with two distinct stages of fusion of n-octanol and Wood’s metal, i.e., melting successively from low to high melting-point debris particles. During the remelting process, the vessel wall temperatures increase with the polar angle firstly and then decrease gradually, leading to the highest temperature appearing in the middle of the lower layer of the stratified molten pool which is finally formed.

Analysis of internal flow characteristics and entropy generation of low head bulb tubular pump

To study the internal flow characteristics and energy characteristics of a large bulb perfusion pump. Based on the CFX software of the ANSYS platform, the steady calculation of the three-dimensional model of the pump device is carried out. The numerical simulation results obtained by SST k-ω and RNG k-ε turbulence models are compared with the experimental results. Finally, SST k-ω is selected for subsequent calculation. With the help of the flow line diagram and turbulent kinetic energy table of the whole flow channel of the pump device, the flow components of the pump device under different working conditions are analyzed, and the pressure and velocity distribution at the impeller and guide vane are analyzed by pressure cloud diagram and velocity cloud diagram. It is found that there are three high-pressure areas in the impeller and guide vane section, and the high-pressure regions are mainly distributed in the middle of the impeller channel. As the head decreases, the pressure at the impeller and guide vane positions decreases gradually, and the flow rate increases. Based on the entropy production principle, the wall entropy production and the distribution of mainstream entropy production at the impeller and guide vane parts are analyzed.