Flow Sodium Research Articles

Mathematical background of the Riga dynamo experiment

The Riga dynamo experiment is a laboratory model of the natural process that is responsible for all environmental magnetic-fields which are generated without human interference. This applies to the field of the Earth, the Sun, stars, and even galaxies which are produced by intense motions of large volumes of good electro-conducting fluids. For our experiment, we use molten sodium – the best liquid electro-conductor available in the laboratory. Approximately 2 m3 of molten sodium are filled into a prolonged cylinder, at the top of which rotates a propeller powered by 200 kW from two motors. The cylinder is divided by thin coaxial inner walls into three parts: in the inner tube the propeller moves the sodium flow helically downward; in the middle one the sodium flows vertically upward; and the outer part contains liquid sodium at rest. When the propeller speed exceeds a critical value (depending on temperature: around 1800 rpm, corresponding to a sodium flow of 0.6 m3 s−1) then a magnetic-field is spontaneously excited. The field pattern slowly rotates around the vertical axis. To enable self-excitation, the sodium flow had been carefully optimized. This article gives an historical overview about the steps in the mathematical description of the Riga dynamo and the optimization of the sodium flow structure. Our analytical model builds on the Ponomarenko configuration, which we modify in four analytical steps. Firstly, the Ponomarenko model was adopted for finite Rm. Then, instead of real generation, we find convective amplification. Secondly, when the outer conductor was replaced with a return tube an absolute instability was attained but at high Rm. Thirdly, to lower Rm a third, immobile conductor was inserted outside and all sizes optimized to achieve global generation at minimum Rm. Adopting these sizes, an experiment was designed and made. Fourthly and finally, the velocity profile was replaced by a trial polynomial to identify the direction in which the flow structure should be corrected.

Experimental research on the incipient boiling wall superheat of sodium

Incipient boiling wall superheat of sodium flowing in annulus was experimentally investigated. The annulus was 800 mm in length, 6 mm as inside diameter and 10 mm as outside diameter. The heat flux in the experiment was from 128 to 846 kW/m2, with inlet subcooling from 63.1 to 287.8 °C, mass flow rate from 7.2 to 122.0 kg/h and system pressure from 0.85 to 28.79 kPa. The experimental results indicated that the incipient boiling wall superheat increased with the increasing heat flux and inlet subcooling. And lower liquid velocity and system pressure could result in a higher incipient boiling wall superheat. Furthermore, a semi-empirical correlation was obtained from the experimental results. It was also found that the predicting results agreed well with the experimental data.

SADHANA facility for simulation of natural convection in the SGDHR system of PFBR

The Prototype Fast Breeder Reactor (PFBR) is a 500 MWe sodium cooled pool type fast reactor being constructed at Kalpakkam, India. PFBR has all the reactor components immersed in the pool of sodium and the fission heat generated in the core, is removed by the sodium circulating in the pool. During normal operation this fission heat is transferred by primary sodium to secondary sodium, which in turn transfers the heat to water in the steam generator for producing steam. The removal of the decay heat generated in the reactor core after the reactor shutdown is also very important to maintain the structural integrity of reactor core components. PFBR employs two independent systems namely, Operational Grade Decay Heat Removal system (OGDHRS) and Safety Grade Decay Heat Removal System (SGDHRS) for decay heat removal. SGDHR system is a passive system working on natural convection to ensure the core coolability even under station blackout condition. It is very important to study the thermal hydraulic behavior of Safety Grade Decay Heat Removal system of PFBR to ensure its reliable operation. A scaled down model of the circuit, named SADHANA has been modeled, designed, constructed and commissioned for demonstration and evaluation of these systems. The facility has completed around 2000 h of high temperature operation. The performance of the experimental system is satisfactory and it meets all the design requirements. At 550 °C sodium pool temperature in test vessel the secondary sodium loop generated a sodium flow of 6.7 m3/h. These experiments have revealed the adequacy and capability of SGDHR system to remove the decay heat from the fast breeder reactor core after its shutdown.

Changes in the major cell envelope components of Mycobacterium tuberculosis during in vitro growth.

One-third of the world's population is infected with Mycobacterium tuberculosis (M.tb), which causes tuberculosis. Mycobacterium tuberculosis cell envelope components such as glycolipids, lipoglycans and polysaccharides play important roles in bacteria-host cell interactions that dictate the host immune response. However, little is known about the changes in the amounts and types of these cell envelope components as the bacillus divides during in vitro culture. To shed light on these phenomena, we examined growth-dependent changes over time in major cell envelope components of virulent M.tb by using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, thin-layer chromatography, mass spectrometry, immunoblotting and flow cytometry. Our studies provide evidence that major mannosylated glycoconjugates on the M.tb cell envelope change as M.tb grows in vitro on the widely used Middlebrook 7H11 agar. In particular, our compositional analyses show that from Day 9 to 28 the amounts of mannose-containing molecules, such as mannose-capped lipoarabinomannan, lipomannan and phosphatidyl-myo-inositol mannosides, change continuously in both the cell envelope and outer cell surface. Along with these changes, mannan levels on the outer cell surface also increase significantly over time. The implications of these differences in terms of how M.tb is grown for studies performed in vitro and in vivo for assessing M.tb-host recognition and establishment of infection are discussed.

A CFD based approach for thermal hydraulic design of main vessel cooling system of pool type fast reactors

A computational fluid dynamics (CFDs) based approach is proposed for the thermal hydraulic design of the main vessel cooling system for pool type sodium cooled reactors. Usage of the proposed method is demonstrated by applying it to a future Indian commercial fast breeder reactor. Towards quantifying the amount of sodium flow rate for the main vessel cooling system, two-dimensional CFD investigations have been performed. The conjugate conduction–convection models adopted for this purpose are validated against sodium experiments available in literature. The required flow fraction has been determined to be 2.6% of core flow, which is 175.6kg/s at full power conditions. The heat loss from the hot pool to the cold pool through the main vessel cooling system is estimated to be 10.6MW at full power and 3.7MW at 20% power conditions. By detailed three-dimensional CFD studies, the effect of ovality in the main vessel cooling annuli due to manufacturing tolerances has been assessed and the associated circumferential temperature difference in the main vessel is determined to be 14°C, which is less than the permissible upper limit of 30°C. The uniformity of sodium flow in the cooling annulus has been investigated by a three-dimensional hydraulic analysis with a view to identify a suitable passive device that can render a uniform velocity distribution. To compare the effectiveness of various devices, a flow mal-distribution index is defined. Detailed parametric studies have been carried out to identify an appropriate porous jet breaker plate configuration.

Nonlinearity of a Voltage-Gated Potassium Channel Revealed by the Mechanical Susceptibility

Voltage-gated ion channels regulate the flows of sodium or potassium ions across nerve cell membranes. A new study of a model potassium channel reveals that behind the channel's regulation of the ion flow lies a viscoelastic molecular structural behavior similar to that of Silly Putty.

Development of a transient thermal-hydraulic code for analysis of China Demonstration Fast Reactor

The transient thermal-hydraulic code THACOS is under development for analysis of China Demonstration Fast Reactor. Applying modular technology, the code contains the core module, the pump module, the sodium pool module and the heat exchanger module and each module could operate separately. It can provide one-dimensional thermal-hydraulic simulation for the primary sodium coolant loop. The point reactor kinetics equations with six-group delayed neutrons have been applied to calculate the core power considering reactivity feedbacks caused by the Doppler effect, coolant density, axial expansion of fuel rods and radial expansion of the core. Multiple-channel model is applied to depict the core. Compressible homogenous flow model is used for the two-phase flow of sodium. The calculated results show that sodium boiling will occur quickly under the ULOF accident without any shutdown rods insertion. While, with the insertion of three hydraulically suspended shutdown rods, the core could be shut down safely and boiling will not occur in a short period of time. Obviously, the passive hydraulically suspended shutdown rods could keep the core safe under ULOF accidents.

Development of a plant dynamics analytical model using flow network for the MONJU ex-vessel fuel storage system

If a station blackout (SBO) occurs in a fast breeder reactor, heat removal by natural circulation is expected, because the height between the heat source and the sink was considered in the plant design to provide the potential for natural circulation. Therefore, many studies about heat removal by natural convection have been reported to date. In these studies, it was determined that the thermal hydraulics for natural circulation depend on the plant structure, cooling system, and component positions, unlike in the case of forced circulation. Thus, the heat removal ability by natural circulation differs in each system and each plant.For the fast breeder reactor (FBR) “MONJU” during normal operation, the ex-vessel fuel storage system (EVSS), which uses a natural circulation flow inside the ex-vessel fuel storage tank (EVST), and the EVST sodium cooling system rely on forced convection with an electromagnetic pump. The decay heat can be removed by air coolers and blowers. If an SBO occurs in this EVSS, all pumps and blowers would be stopped. However, the plant dynamics of the EVSS in the time after all the pumps and the blowers were tripped has not yet been evaluated.Therefore, in this study, a plant dynamics analysis model was developed using a flow network to calculate the entire dynamics of the EVSS in the event of an SBO. The Super-COPD program, which has been validated for models of the reactor and the main cooling system using several tests including the plant trip test and the natural circulation test, was used. A model of the EVSS was developed by considering the design information, and the modeling technique was based on specific analytical models for the reactor and the main cooling system, because there was no sufficient data to confirm the behavior of the sodium temperature and flow in this EVSS. For the model to simulate natural circulation, the heat capacity of the coolant plenum of the EVST, geometrical information such as the height of the components, and the heat transfer characteristics of the cooling coils were considered.Based on a comparison to experimental data, it was confirmed that the calculated the behavior of the sodium temperature and flow of the EVST sodium cooling system in an SBO is accurate. The thermal center of the heat transfer area of only the helical coils decreased to approximately 21% in comparison with that under normal operation, and the flow rate in the EVST decreased by approximately 20%. The natural convection force depends on the differences in the densities and the thermal centers of the heat transfer areas between each component. The calculation results based on the theory were almost equivalent to the analysis results. It is estimated that the developed model correctly considered the heat transfer characteristics of each component and can accurately calculate the natural convection force.From these results, it is concluded that the developed model for the EVSS is effective for calculating the temperature and flow behavior of the entire system under natural circulation conditions like those expected during an SBO. In the future, these models will be validated using a 3D fluid dynamics analysis and additional test results.

Investigations of flow and temperature field development in bare and wire-wrapped reactor fuel pin bundles cooled by sodium

Simultaneous development of liquid sodium flow and temperature fields in the heat generating pin bundles of reactor has been investigated. Development characteristics are seen to be strongly influenced by pin diameter, number of pins, helical wire-wrap, ligament gap between the last row of pins and hexcan wall and Reynolds number. Flow development is achieved within an axial length of ∼125 hydraulic diameters, for all the pin bundle configurations considered. But temperature development is attained only if the pin diameter is small or the number of pins is less. In the case of large pin diameter with more pins, temperature development could not be achieved even after a length of ∼1000 hydraulic diameters. The reason for this behavior is traced to be the weak communication among sub-channels in tightly packed bundles. It is seen that the pin Nusselt number decreases from center to periphery in a bundle. Also, if the ligament gap is narrow, the Nusselt number is large and more uniform. Flow development length is short if the Reynolds number is large and the converse is true for thermal development length. Helical wire-wrap shortens the thermal entry length and significantly enhances the global Nusselt number. But, its influence on hydrodynamic entry length is not significant.

Protective Effect Of Bosentan In Experimental Cerebral Ischemia-Reperfusion Injury

OBJECTIVE: In cerebral ischemia, there are many factors that start the events leading to cell death. These factors contain free radical production, excitotoxicity, sodium and calcium flow disruption, enzymatic changes, stimulation of the inflamatuar process, the activation of platelets and leukocytes, delayed coagulation, endothelial dysfunction and endothelin (ET) release. Bosentan is the competitive antagonist of endothelin receptors; ETA and ETB. The aim of this study is to determine whether the protective effects of bosentan in experimental cerebral ischemia reperfusion injury. MATERIAL and METHODS: In this study, after ischemia-reperfusion procedure, bosentan molecule was regularly given to rats for 5 days. The brain tissues of decapitated rats were histopathologically examined. The levels of oxidant and antioxidant were determined in these brain tissues. RESULTS: It was observed that antioxidant levels and histopathological examinations were in rats given bosentan better than control group rats. CONCLUSION: In conclusion, this study has showed that bosentan may be an agent which could reduce negative effects resulting from neuronal death associated with ischemic stroke.

Magnetic field advection in liquid sodium flow in toroidal channel

Magnetic field advection in liquid sodium flow in toroidal channel

E203 レーザ計測技術を用いたナトリウム-水化学反応場の反応経路解析(OS8 軽水路・新型炉・原子力安全(4))

In a sodium-cooled fast reactor (SFR), liquid sodium is used as a heat transfer fluid because of its excellent heat transport capability. On the other hand, it has strong chemical reactivity with water vapor. One of the design basis accidents of the SFR is the water leakage into the liquid sodium flow by a breach of heat transfer tubes. Therefore, the study on sodium-water chemical reactions is of importance for security reasons. This study aims to clarify the gas phase sodium-water reaction path and reaction products Na, Na_2, H_2O, and reaction products in the counter-flow sodium-water reaction field were measured using laser diagnostics such as Raman scattering and photo-fragmentation. The main product in the sodium-water reaction was determined to be NaOH and its reaction path was discussed using Na-H_2O elementally reaction analysis.

Development of sputter ion pump based SG leak detection system for Fast Breeder Test Reactor

The Fast Breeder Test Reactor (FBTR) is a 40MWt, loop type sodium cooled fast reactor built at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam as a fore-runner to the second stage of Indian nuclear power programme. The reactor design is based on the French reactor Rapsodie with several modifications which include the provision of a steam-water circuit and turbo-generator. FBTR uses sodium as the coolant in the main heat transport medium to transfer heat from the reactor core to the feed water in the tertiary loop for producing superheated steam, which drives the turbo-generator. Sodium and water flow in shell and tube side respectively, separated by thin-walls of the ferritic steel tubes of the once-through steam generator (SG). Material defects in these tubes can lead to leakage of water into sodium, resulting in sodium water reactions leading to undesirable consequences. Early detection of water or steam leaks into sodium in the steam generator units of liquid metal fast breeder reactors (LMFBR) is an important requirement from safety and economic considerations. The SG leak in FBTR is detected by Sputter Ion Pump (SIP) based Steam Generator Leak Detection (SGLD) system and Thermal Conductivity Detector (TCD) based Hydrogen in Argon Detection (HAD) system. Many modifications were carried out in the SGLD system for the reactor operation to improve the reliability and availability. This paper details the development and the acquired experience of SIP based SGLD system instrumentation for real time hydrogen detection in sodium for FBTR.

Side Effects of Cocaine Abuse: Multiorgan Toxicity and Pathological Consequences

Cocaine is a powerful stimulant of the sympathetic nervous system by inhibiting catecholamine reuptake, stimulating central sympathetic outflow, and increasing the sensitivity of adrenergic nerve endings to norepinephrine (NE). It is known, from numerous studies, that cocaine causes irreversible structural changes on the brain, heart, lung and other organs such as liver and kidney and there are many mechanisms involved in the genesis of these damages. Some effects are determined by the overstimulation of the adrenergic system. Most of the direct toxic effects are mediated by oxidative stress and by mitochondrial dysfunction produced during the metabolism of noradrenaline or during the metabolism of norcocaina, as in cocaine-induced hepathotoxicity. Cocaine is responsible for the coronary arteries vasoconstriction, atherosclerotic phenomena and thrombus formation. In this way, cocaine favors the myocardial infarction. While the arrhythmogenic effect of cocaine is mediated by the action on potassium channel (blocking), calcium channels (enhances the function) and inhibiting the flow of sodium during depolarization. Moreover chronic cocaine use is associated with myocarditis, ventricular hypertrophy, dilated cardiomyopathy and heart failure. A variety of respiratory problems temporally associated with crack inhalation have been reported. Cocaine may cause changes in the respiratory tract as a result of its pharmacologic effects exerted either locally or systemically, its method of administration (smoking, sniffing, injecting), or its alteration of central nervous system neuroregulation of pulmonary function. Renal failure resulting from cocaine abuse has been also well documented. A lot of studies demonstrated a high incidence of congenital cardiovascular and brain malformations in offspring born to mothers with a history of cocaine abuse.

Modeling of permanent magnet flowmeter for voltage signal estimation and its experimental verification

Prototype Fast Breeder Reactor (PFBR) is a 500MWe, sodium cooled, pool type, mixed oxide (MOX) fueled reactor. Sodium flow measurement in various loops of the reactor is of prime importance from the operational and safety aspects. To measure the flow of electrically conducting liquid sodium in secondary circuits, permanent magnet flowmeters (PMFMs) made up of ALNICO-5 are used in Fast Breeder Test Reactor (FBTR), PFBR and existing sodium loops in Indira Gandhi Centre for Atomic Research (IGCAR). PMFM made up of ALNICO-5 are bulky and heavy, hence to reduce size of flowmeter a PMFM made up of Samarium Cobalt (SmCo) is designed and calibrated in existing sodium loop. Calibration of flowmeter requires dedicated sodium rig with pipe sizes of same dimension as flowmeter pipe, which needs modification in existing system. As an alternate method of sodium calibration, three dimensional Finite Element Modeling of SmCo PMFM is done for its voltage signal prediction. In simulation magnetic field distribution across the flowmeter pipe and effect of sodium flow on magnetic field are analyzed. Effect of sodium temperature on flowmeter voltage signal and its change with change in sodium flow rate is predicted with modeling and compared with experimental tests conducted for use of PMFM.

Habitual dietary sodium intake is inversely associated with coronary flow reserve in middle-aged male twins

Evidence links dietary sodium to hypertension and cardiovascular disease (CVD), but investigation of its influence on cardiovascular function is limited. We examined the relation between habitual dietary sodium and coronary flow reserve (CFR), which is a measure of overall coronary vasodilator capacity and microvascular function. We hypothesized that increased sodium consumption is associated with lower CFR. Habitual daily sodium intake for the previous 12 mo was measured in 286 male middle-aged twins (133 monozygotic and dizygotic pairs and 20 unpaired twins) by using the Willett food-frequency questionnaire. CFR was measured by positron emission tomography [N(13)]-ammonia, with quantitation of myocardial blood flow at rest and after adenosine stress. Mixed-effects regression analysis was used to assess the association between dietary sodium and CFR. An increase in dietary sodium of 1000 mg/d was associated with a 10.0% lower CFR (95% CI: -17.0%, -2.5%) after adjustment for demographic, lifestyle, nutritional, and CVD risk factors (P = 0.01). Across quintiles of sodium consumption, dietary sodium was inversely associated with CFR (P-trend = 0.03), with the top quintile (>1456 mg/d) having a 20% lower CFR than the bottom quintile (<732 mg /d). This association also persisted within pairs: a 1000-mg/d difference in dietary sodium between brothers was associated with a 10.3% difference in CFR after adjustment for potential confounders (P = 0.02). Habitual dietary sodium is inversely associated with CFR independent of CVD risk factors and shared familial and genetic factors. Our study suggests a potential novel mechanism for the adverse effects of dietary sodium on the cardiovascular system. This trial was registered at clinicaltrials.gov as NCT00017836.

Multi dimensional analysis of Design Basis Events using MARS-LMR

Abstract KALIMER-600 (Korea Advanced Liquid Metal Reactor), which is a pool type SFR (Sodium-cooled Fast Reactor), was developed by KAERI (Korea Atomic Energy Research Institute). DBE (Design Basis Events) for KALIMER-600 has been analyzed in the one dimension. In this study, the one dimensional analyzed sodium hot pool is modified to a three dimensional node system, because the one dimensional analysis cannot represent the phenomena of the inside pool of a big size pool with many compositions, such as UIS (Upper Internal Structure), IHX (Intermediate Heat eXchanger), DHX (Decay Heat eXchanger), and pump. The results of the multi-dimensional analysis compared with the one dimensional analysis results in normal operation, TOP (Transient of Over Power), LOF (Loss of Flow), and LOHS (Loss of Heat Sink) conditions. First, the results in normal operation condition show the good agreement between the one and multi-dimensional analysis. However, according to the sodium temperatures of the core inlet, outlet, the fuel central line, cladding and PDRC (Passive Decay heat Removal Circuit), the temperatures of the one dimensional analysis are generally higher than the multi-dimensional analysis in conditions except the normal operation state, and the PDRC operation time in the one dimensional analysis is generally longer than the multi-dimensional analysis. In particular, we can see the reverse and mixing flow phenomena in LOHS better than TOP and LOF, which affect the peak temperature in the one dimensional analysis at 330 s but is not observed in the multi-dimensional analysis. In addition, the different temperatures at the central line of fuel and cladding are shown due to different mass flow in the core. The two PDRCs show the almost same results in one and multi-dimensional analysis, respectively. However, in the comparison between the one and multi-dimension, the heat removal capability of PDRC in the multi-dimensional analysis is better than the one dimensional analysis at the beginning of calculation. The aspects change at the ending of calculation due to the different mass flow in PDRC and over flow sodium temperature. In wrap up, the sodium temperatures of the core in the one dimensional analysis are generally higher than the multidimensional analysis. The temperature peak point in the one dimensional analysis under LOHS does not show in the multi-dimensional analysis, because the reverse and mixing flow pattern between the hot pool and the core outlet region. Even thought there are some different results between the two different dimensional analyses, we can say that the KALIMER-600 system has the safety margins.

MHD stability analysis of a liquid sodium flow at the annular gap of an EM pump

A stability analysis of a viscous, incompressible, and electrically conducting liquid sodium flow in an annular linear induction electromagnetic pump for sodium coolant circulation of a Sodium Fast Reactor (SFR) was carried out when transverse magnetic fields permeate the sodium fluid across the narrow annular gap. Due to a negligible skin effect and the presence of a magnetic core outside the gap, radial magnetic field is assumed to be constant over the narrow channel gap, and the steady state solution of the axial velocity is obtained as a function of radius. Small perturbations for MHD fields were considered in sinusoidal form as a function of the angular frequency and wave number, and the resulting equations were linearized. The solutions of the perturbed equations were sought in the form of a linear combination of independent orthogonal functions in a non-dimensional radial interval (0,1), and each orthogonal function was chosen to satisfy the boundary conditions of adhesion to the solid walls of the channel. Under the assumption that solutions of the equations were not oscillated rapidly according to the radial coordinate, finite numbers of orthogonal polynomials were considered. As a result, simultaneous equations with coefficients of steady-state solutions were arranged, and dispersion relations between angular frequency and wave number of perturbed state were sought. The imaginary part of the angular frequency was taken into consideration from the condition of existence of a nontrivial solution of the system, which leads to the relation between critical Reynolds number (Recr) and Hartmann number (Ha). In the present study, critical Reynolds number and wave numbers were plotted against the Hartmann number for a long wave perturbation; thus, it was shown that a magnetic field has a significant stabilizing effect on liquid sodium flow.

Turbulent viscosity and turbulent magnetic diffusivity in a decaying spin-down flow of liquid sodium

The free decay of a strong flow of liquid sodium (at Reynolds number defined via the maximal mean velocity and the radius of the channel cross section up to Re≈3×10(60) and the corresponding magnetic Reynolds number up to Rm≈30) generated by the sudden stop of a rapidly rotating toroidal channel is studied experimentally. The toroidal and poloidal components of velocity are measured using a potential probe. We describe the onset of motion, the evolution of strongly anisotropic fluctuations, and the homogenization and decay of turbulence in the final period. We analyze the statistical characteristics of velocity fields in relation to the behavior of effective magnetic diffusivity estimated from measurements of the phase shift between the induced and applied magnetic fields. For the late (self-similar) decay of turbulent flow, turbulent viscosity is shown to be dependent on the root-mean-square velocity pulsations and can be expressed as νt∼νRe1.3. The behavior of turbulent magnetic diffusivity depends on the magnetic Reynolds number defined in terms of the root-mean-square velocity pulsations. At low magnetic Reynolds numbers (Rmrms<1), turbulent magnetic diffusivity grows rapidly with increasing velocity pulsations (ηt∼ηRmrms2). If the magnetic Reynolds number exceeds unity, the behavior of turbulent magnetic diffusivity becomes similar to the behavior of turbulent viscosity. The highest values of turbulent magnetic diffusivity are achieved at the end of braking, which corresponds to the transient stage of a strongly anisotropic turbulent flow in which the poloidal velocity oscillations prevail.

Avaliação e recomendações nutricionais para crianças e adolescentes com fibrose cística

OBJETIVO: Revisar e discutir evidências sobre a avaliação do estado nutricional e as recomendações para o tratamento nutricional de crianças e adolescentes com fibrose cística. FONTES DE DADOS: Bancos de dados MEDLINE (versão PubMed) e Latin American and Caribbean Center on Health Sciences Information (LILACS), entre 1984 a 2009. Aplicou-se a combinação dos seguintes descritores: fibrose cística, estado nutricional, criança e adolescente - em inglês e português. SÍNTESE DOS DADOS: A fibrose cística é uma doença genética, de evolução crônica, progressiva e fatal. Resulta do defeito na proteína reguladora transmembrana que regula a condução de cloro e, consequentemente, o fluxo de sódio e água através da membrana apical das células epiteliais. Pacientes fibrocísticos são vulneráveis à desnutrição, que resulta do desequilíbrio entre ingestão alimentar, gasto e perdas energéticas. Novos conhecimentos sobre a fisiopatologia da doença, adquiridos nas últimas décadas, resultaram em mudanças significativas nas atuais recomendações energéticas e principalmente de lipídeos. A importância da nutrição no bem-estar e sobrevida dos fibrocísticos está bem estabelecida, assim como a associação entre a desnutrição e a deterioração da função pulmonar. Existem múltiplos fatores inter-relacionados que afetam o estado nutricional, tais como, mutação genética, insuficiência pancreática, ressecção intestinal, perda de sais e ácidos biliares, refluxo gastroesofágico, inflamação e infecções pulmonares, diabetes e condições emocionais. CONCLUSÕES: O monitoramento nutricional e o aconselhamento dietético são elementos chave no manejo de crianças e adolescentes com fibrose cística com o intuito de controlar a sintomatologia e a progressão da doença, proporcionando melhor qualidade de vida.