Diagnostic Neutral Beam Research Articles

Event driven high speed data acquisition with IEEE 1588 synchronization for long pulse operations of Indian Test Facility for ITER DNB

The Indian Test Facility (INTF) is a negative Hydrogen ion based 100 kV, 60A, 5 Hz modulated NBI system having duty cycle of 3 s ON time to 20 s OFF time. Prime objective of the facility is to characterize ITER Diagnostic Neutral Beam (DNB) with full specifications, prior to shipment and installation in ITER. In order to fully characterize ITER DNB, a matured Data Acquisition and Control system (DACS) is needed which will be responsible for supervisory control of the facility and for acquiring and monitoring signals at run time. Apart from conventional DACS, high speed data acquisition is needed for diagnostics and other signals with sampling rate requirements of 100 MS/s. For acquiring data from such systems it is imperative that the data be acquired only for certain duration on the occurrence of the event. Such acquisition systems are classified as event driven data acquisition system and are widely used in fusion engineering community.Development and implementation of high speed event driven data acquisition systems pose challenges in terms of data buffering, data streaming and synchronization. The precise timing of the event occurrence with respect to the main pulse should also be known for which a timing and synchronization system is needed. To fulfill this purpose, IEEE 1588 protocol offers a network based method of synchronizing multiple nodes based on Ethernet with sub microsecond accuracy. The present work describes the development of an event driven high speed data acquisition in synchronization with IEEE 1588 based timing network. The work proposes the time stamping of the event from synchronized network integrated with the event acquisition platform. The developed system has been tested for pulse durations longer than 3600 s. The performance of event data acquisition system has been thoroughly characterized and improved by applying various software optimizations in LabVIEW. The present work although intended to be used for INTF can be used for any such facility in fusion or other areas.The paper provides results of IEEE 1588 based timing network in various configurations and event data acquisition system developed on high speed FPGA controlled digitizer board with prototype results.

Microwave ion source with dual helical antenna for diagnostics neutral beam of ALBORZ tokamak

An efficient ion source of the diagnostic neutral beam injection (DNBI) is designed and simulated for Alborz Tokamak, based on the microwave plasma source. The diagnostic neutral beam is designed for use in some diagnostics system such as charge-exchange recombination spectroscopy (CXRS), Rutherford Scattering (RS), and Motional Stark Effect (MSE) of Alborz Tokamak. In this work, a new helical antenna is designed and simulated for a microwave plasma source, to reach a plasma density of order8.23×1017m−3. The microwave plasma source is employed by the high-efficient ion beam accelerator. In this simulation, three-electrodes in different potentials of 20 kV, −2 kV, and grounded respectively, are used as extraction system of the ion beam source. According to our design, nine apertures grids are considered for the accelerator system. The simulation results show that, the system can extract an ion beam with energy and current of 20 keV and 60 mA respectively. The extracted ion beam consists of nine beamlets, where the beam waist and the current of each of them are calculated about 3 mm and 6.5 mA, respectively. The results of this work indicate that the ion beam with minimum divergence angle of 32 mrad can be generated by the proposed ion beam source.

Influence of positive ions on the beamlet optics for negative-ion neutral beam injectors

Neutral beam injectors are based on the neutralization of ion beams accelerated at the desired energy. In the case of the ITER heating and diagnostic neutral beams, the target heating power translates into stringent requirements on the acceptable beamlet divergence and aiming to allow the beam to reach the fusion plasma. The beamlets composing the accelerated beam are experimentally found to feature a transverse velocity distribution exhibiting two Gaussian components: the well-focused one is referred to as the core component while the rest of the beam, the halo, describes beam particles with much worse optics. The codes that simulate beam extraction and acceleration usually assume that the negative ions move towards the plasma meniscus with a laminar flow (no transverse velocity) or that the transverse velocity distribution can be modelled as a Maxwellian and that the current density is uniformly illuminating the meniscus; under such approximations, the presence of highly divergent components cannot be explained. In this work, we develop a simple test-particle tracing code with Monte Carlo collisions, named ICARO (for Ions Coming Around), to study the transport of negative ions in the extraction region and derive the spatial and velocity distribution of the negative ions at the meniscus (i.e. the plasma boundary where a beamlet is extracted). In particular, the origin of the beamlet halo and its dependence on the source parameters are discussed, highlighting as a key parameter the energy distribution of positive ions in the source plasma.

The SPIDER Pulse Plant Configuration Environment

At the ITER Neutral Beam Test Facility, the Source for the Production of Ions of Deuterium Extracted from Radio frequency plasma (SPIDER) has been in operation since 2018 aiming at prototyping the heating and diagnostic neutral beam appliances in view of the ITER demanding requirements for plasma burning conditions and instabilities control. For the sake of safety, machine protection and efficiency it is necessary to follow an accurate planning strategy and approval action of the experiment parameter settings. Although the initial tools available for the SPIDER integrated commissioning and early campaigns offered the basic functionality to perform the necessary tasks, there were a set of relevant issues that were identified as needing improvements for an efficient and safe configuration environment. Namely, the fact that there were no tools indicating the parameters change since the previous pulse, or the lack of a comparison tool between a new set of parameters and a previous setup, demanded a tedious and error prone verification of all parameters in the sequence. Moreover, several verifications should be automated according to the machine safety limits, increasing the safety check by human and automated machine (algorithmic) validation. This contribution depicts (i) the approval sequence designed for SPIDER safe operation; (ii) the configuration environment requirements according to the SPIDER pulse preparation procedure; (iii) the decision of the development tools used for implementation and design; (iv) the implementation details and preliminary tests of the global environment.

Digital Control and Power Systems for the Pegasus-III Experiment

The PEGASUS-III experiment is a solenoid-free, low aspect ratio spherical tokamak that will serve as a dedicated U.S. platform for comparative nonsolenoidal tokamak plasma startup studies. Approximately 175 megavolt-ampere (MVA) of reconfigured and expanded programmable power systems, 7 MJ of new stored energy, and new digital control and protection systems for the facility are being commissioned to support PEGASUS-III upgrades. These include: increased toroidal field (0.15–0.6 T); new divertor and poloidal field coils; increased pulse length; local and coaxial helicity injectors for solenoid-free plasma initiation; radio frequency (RF) systems for heating and current drive; and a diagnostic neutral beam (DNB). A new real-time digital control system implements 16 proportional-integral differential (PID) feedback controllers with 25 kHz loop rates to control the electromagnets and helicity injectors. The poloidal field coils, helicity injector arc currents, and toroidal field are driven by 36 3.6 MVA (4 kA, 900 V) insulated-gate bipolar transistor (IGBT) buck converters. Helicity injector bias voltage and current will be provided by a set of four 10.8 MVA multi-level buck converters (MLBCs). Each is comprised of an 1800 V integrated gate-commutated thyristor (IGCT) stage and a ±900 V IGBT stage in series, providing controllable <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$I_{\mathrm {inj}}\le 4$ </tex-math></inline-formula> kA at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\mathrm {inj}}\le 2.7$ </tex-math></inline-formula> kV. A field programmable gate array (FPGA)-based digital fault protection system multiplexes controller commands to individual power semiconductors in these supplies, monitors their operational status, and executes shutdown sequences within <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10~\mu \text{s}$ </tex-math></inline-formula> of fault detection. An 80 kV, 4 A zero-voltage-switching (ZVS) resonant converter with < 1% output ripple is under development for the DNB and is being evaluated as a topology to drive RF sources.

Upgraded main ion charge exchange recombination spectroscopy on the C-2W field reversed configuration (FRC) plasma.

A prototype main-ion CHarge Exchange Recombination Spectroscopy (mCHERS) diagnostic is providing measurements of the main-ion (hydrogen or deuterium) temperature and velocity in the C-2W field reversed configuration plasma using charge exchange Balmer-alpha emission at five different radial locations with 500Hz frequency and a per-pixel velocity resolution of 15 km/s. Measurement along the entire plasma radius of C-2W is enabled by a diagnostic neutral beam (DNB) that passes through the center of plasma, unlike the larger diameter heating neutral beams that have impact parameters of 20cm. DNB provides high time resolution via beam modulation and spatial resolution via its small cross section. The goals of the current mCHERS upgrade are to double the number of spatial channels, improve the per-pixel velocity resolution by three times, and increase the measurement frequency to match the maximum modulation frequency of the diagnostic neutral beam (∼10kHz). To accomplish these goals, a new astigmatism-free Isoplane spectrometer has been commissioned. Progress and results from the newly upgraded mCHERS system are detailed.

Comparison of Doppler back-scattering and charge exchange measurements of E × B plasma rotation in the DIII-D tokamak under varying torque conditions

Measurements of the E × B toroidal angular velocity, ( is the radial electric field, B θ is the poloidal magnetic field), are made using the Doppler back-scattering (DBS) and charge-exchange recombination (CER) spectroscopy diagnostics. DBS uses the Doppler shift of wavenumber-resolved density fluctuations while CER uses the Doppler shift of impurity emission lines to independently measure plasma parameters for calculating the local radial electric field. DBS and CER profiles of as a function of normalized toroidal flux (ρ) are compared at various levels of neutral beam applied torque on the plasma. Under standard neoclassical theory is a flux surface quantity, making it appropriate to compare across diagnostics. DBS and CER generally show good agreement when comparing profiles at different levels of neutral beam injection-applied torque. Furthermore, the DBS values have close to the same precision as CER values when averaged over a similar time-scale and effects, such as prompt-torque are considered. DBS is able to observe the rapid (10 ms) modification of the profile by the diagnostic neutral beam ‘blips’. This modification is most pronounced when the blip applies a large relative change in torque on the plasma. Overall, these results could have implications on transport analysis and suggests using DBS and CER in conjunction to constrain values of the E × B-shear (sometimes called ).

Laser welded lip seal for UHV class fusion vessels–A methodical study

Lip seals are considered, the most promising options for the vacuum boundary joints in large size vacuum vessels (like rectangular neutral beam vessel with an opening size of ∼30 m) of fusion machines. Lip seals are designed with the corner welding of 2 mm thickness sheets of SS304L with the welding penetration requirement of 3 mm. With the first phase of development, laser welding parameter optimization and the sensitivity analysis was carried out to understand the effect of manufacturing tolerances (like air gap between the plates, laser beam misalignment and plate misalignment) on the weld quality. To ascertain the defined tolerances, a specialized clamping tool was configured, designed, manufactured and tested by integrating that with the assembly of laser welding head and robotic arm. For the prototype welding demonstration, the Lip seal welding of a rectangular configuration and an elliptical configuration of size 3 m × 1.5 m (∼1/3rd size of Diagnostic Neutral Beam (DNB) vessel lip seal); and 1 m length with 1.2 m diameter (exact size of DNB high voltage bushing lip seal) are considered. Welding qualification was done with the Non-Destructive and Destructive examinations. Further, the camera based feedback system for the seam tracking was incorporated to the system, which enables the remote detection and correction of the weld path. This development also extended to enable the repair of welding operation.

Overview of diagnostics on a small-scale RF source for fusion (ROBIN) and the one planned for the diagnostic beam for ITER.

India is responsible for the supply of diagnostic neutral beam systems for ITER to diagnose its helium ash during the deuterium-tritium plasma phase using the charge exchange recombination spectroscopy technique. Considering the many first of its kind in terms of technologies and beam development aspects, ITER Indian domestic agency has adopted a strategy of developing the technology and beam experimentation in parallel. On the beam development front three test beds, namely, the ROBIN (Rf Operated Beam source in India for Negative ion research), the TWIN (TWo rf driver-based Indigenously built Negative ion source), and the INTF (INdian Test Facility) are presently in their various phases of operation, optimization, and setting up at IPR, respectively. Experiments related to plasma production, beam production, and acceleration up to 30keV in volume and surface mode have been performed on ROBIN. The maximum negative hydrogen ion current density to a tune of 27 mA/cm2 is obtained in the surface mode with Cs injection. Optimal source performance requires optimal surface conditions, minimum impurities, careful characterization of the plasma, cesium feed and its redistribution, and optimal wall temperatures of the surfaces of the plasma box and the plasma grid. A combination of probe, optical, vacuum, laser based, electrical, and calorimetric diagnostic measurements enables such a control. At ROBIN, the above diagnostics are being used regularly. The operational and diagnostic experiences on ROBIN shall provide the desired experience and database for operations of TWIN and INTF in the coming years. A large number of conventional and advanced diagnostic techniques are used for plasma and beam characterization. These diagnostics are suitable not only to detect and understand the plasma but also for studies related to impurity evolution. The temporal evolution of impurities significantly impacts the plasma and beam properties. The studies help in establishing correlations between physical parameters and operational parameters to optimize the source performance ensuring adequate safety and investment protection. This paper will present a brief overview of various diagnostics implemented, lessons learned, and the results obtained from ROBIN. In addition, an outline of the diagnostics planned for INTF based on the experience and understandings developed during the present experiments on ROBIN and TWIN and considering the requirements of large systems shall be discussed.

Feasibility of neutral particle analysis for fast-ion measurements at W7-X

A preliminary study investigating capabilities of a planned but not yet installed neutral particle analyzer (NPA) [1,2] system combined with a diagnostic neutral beam at Wendelstein 7-X (W7-X) [3] is presented. Additionally two NPAs viewing the neutral beam injection (NBI) [4] source 8 beam and using it as neutral source are studied. The main focus is laid on what information about NBI fast-ion slowing down distributions can be inferred from active NPA measurements when altering the magnetic configuration, plasma β, density, electron temperature or radial electric field. For an order of magnitude estimation of the passive signal a model for penetration of neutral hydrogen recycling from the first wall is implemented. For the active signal a diagnostic neutral beam injector was simulated using FIDASIM [5]. The fast-ion slowing down distributions were calculated with ASCOT [6]. The synthetic NPA signal is found in general to be sensitive to changes in the fast-ion distribution function. Distinct features can be seen in the high energy active signal in the high-mirror configuration when changing β, especially, when looking at deeply trapped fast particles. However, for the initially planned installation geometry of the NPA diagnostic most fast-ion distributions exhibit only small differences in the magnitude and especially shape. In a high density case in the standard magnetic configuration with a central β of 8%, the fast-ion density in the core region is too low to provide a measurable flux of charge exchanged neutrals. The passive signal from the inner plasma regions is found to be negligible compared to the active signal.

Main ion charge exchange recombination spectroscopy on C-2W FRC plasmas.

A main ion charge exchange recombination spectroscopy (mChERS) diagnostic has been developed to measure the velocity and temperature of the main deuterium ions in the C-2W (also called Norman) field-reversed configuration (FRC) device. A modulated diagnostic neutral beam (DNB) of hydrogen with 40 keV full energy and a nominal current of 8.5A provides the charge exchange signal. The DNB can achieve a fast modulation frequency of up to 10 kHz, a rare attribute to find on other fusion devices, which defines the time resolution of mChERS. Currently, the mChERS diagnostic provides simultaneous measurements at five spatial locations in the FRC plasma using a high-speed camera. The design and capabilities of the mChERS system are presented along with first experimental data.

Development of beam emission spectroscopy in the helically symmetric experiment stellarator

This study shows the feasibility of a beam emission spectroscopy (BES) diagnostic in the Helically Symmetric eXperiment (HSX) stellarator for obtaining the spatiotemporal structure of density fluctuation. A beam emission simulation was applied to HSX plasmas to design and optimize viewing chords and to estimate the beam emission spectrum. A Doppler-shifted beam emission spectrum was measured from a 30 kV, 4A diagnostic neutral beam injected into HSX plasmas. The beam emission was measured with a high-time-resolution avalanche photodiode (APD) assembly to determine the feasibility of BES in HSX. For HSX plasmas heated by 28GHz electron cyclotron heating, a mode around f = 15 kHz was observed in the BES signal. The coherence between the BES signal and the density fluctuation measured by an interferometer system was significant. A plan for improving the BES system to enable the measurement of higher frequency related to turbulent transport is presented. The array of sightlines proposed in this study can be used to measure beam emission with a Doppler shift larger than 3nm (blue shift), which enables the use of a wide passband interference filter to obtain higher throughput. The adoption of a large objective optics and a chilled APD assembly will improve the signal-to-noise ratio.

First tests and commissioning of the emittance scanner for SPIDER

SPIDER is the prototype ion source for ITER Heating and Diagnostic Neutral Beams. To investigate the phase-space distribution of its beamlets, an Allison type emittance scanner was developed. This kind of diagnostic is widely used in ion sources for high-energy accelerators, but has never been employed in fusion-relevant ion sources. Its measurements will assess the optics properties of the beamlets of a large negative ion source, providing a local measurement of their phase-space structure, and they will be useful to validate numerical models. This paper presents the experimental setup of the diagnostic, describing the detector, its integration in SPIDER, the handling system and the control electronics. The effectiveness of the design of the detector Faraday cup to repel secondary electrons is experimentally proven. Finally, the emittance measurements obtained in a dedicated test facility are also reported and compared with ray tracing simulations.

Measurements of impurity ion temperature and velocity distributions via active charge-exchange recombination spectroscopy in C-2W.

In TAE Technologies' C-2W experiment, electrode biasing is utilized for boundary control of a field-reversed configuration (FRC) plasma embedded in a magnetic mirror. Understanding the underlying physics associated with FRC rotation, stabilization, and heating is crucial for improving machine performance. Impurity ion rotation and temperature are sensitive to biasing effects, and measurements of these quantities can provide insight into important plasma dynamics and overall effectiveness of the biasing system. To this end, a charge-exchange recombination spectroscopy (ChERS) diagnostic was developed and deployed to measure local impurity ion temperature and velocity in the confinement vessel of C-2W. The system utilizes a new diagnostic neutral beam (40 keV, 8.5A) and a fiber-coupled spectrometer with an image-intensified high-speed camera to measure beam-induced spectral line emission at multiple lines-of-sight. Design details and the first experimental results obtained with this new diagnostic are presented and discussed.

Main design features of the Rh-based first mirror developed for the ITER CXRS core diagnostics

The ITER core charge exchange recombination spectroscopy, which contains five in-port optical mirrors, is intended to transfer the visible light emitted by interaction of the plasma with the diagnostic neutral beam to the corresponding spectrometers. The first mirror (M1) is a key and the most vulnerable component of the diagnostics. In order to provide the required mirror lifetime, maintainability and structural integrity, M1 is composed of special materials, i.e. it is made of a thin 1 mm single-crystal rhodium (ScRh) plate diffusion bonded to a specially matched tungsten-copper substrate. A rhodium nanocrystalline coating (NcRh) can be an option.The paper presents the evolution of the M1 design developed for the optical layout of 2018. M1 is adjustable and cleanable with about 100÷500 procedures of 60 MHz plasma discharge. The mirror design is supported by multifield thermal, electromagnetic and structural analyses and uses experimental data of R&Ds made by Forschungszentrum Juelich, Germany. The study confirms the working capacity of the developed mirror solution.

The integrated diagnostic suite of the C-2W experimental field-reversed configuration device and its applications.

In the current experimental device of TAE Technologies, C-2W (also called "Norman"), record breaking advanced beam-driven field-reversed configuration (FRC) plasmas are produced and sustained in steady state utilizing variable energy neutral beams (15-40 keV, total power up to 20MW), advanced divertors, bias electrodes, and an active plasma control system. This fully operational experiment is coupled with a fully operational suite of advanced diagnostic systems. The suite consists of 60+ individual systems spanning 20 categories, including magnetic sensors, Thomson scattering, interferometry/polarimetry, spectroscopy, fast imaging, bolometry, reflectometry, charged and neutral particle analysis, fusion product detection, and electric probes. Recently, measurements of main ion temperatures via a diagnostic neutral beam, axial profiles of energy flux from an array of bolometers, and divertor and edge plasma parameters via an extensive set of electric probes, interferometers, and spectrometers have all been made available. All the diagnostics work together to provide a complete picture of the FRC, fast-ion inventory, and edge plasma details enabling tomographic reconstruction of plasma parameter profiles and real-time plasma control.

Data for Beryllium–Hydrogen Charge Exchange in One and Two Centres Models, Relevant for Tokamak Plasmas

Data on the cross section and kinetic rate of charge exchange (CX) between the bare beryllium nucleus, the ion Be(+4) and the neutral hydrogen atom are of great interest for visible-range high-resolution spectroscopy in the ITER tokamak because beryllium is intended as the material for the first wall in the main chamber. Here an analysis of available data is presented, and the data needs are formulated. Besides the active probe signal produced by the CX of the diagnostic hydrogen neutral beam with impurity ions in plasma, a passive signal produced by the CX of impurity ions with cold edge plasma is also important, as it shows in observation data from the JET (Joint European Torus) tokamak with an ITER-like beryllium wall. Data in the range of a few eV/amu to ~100 eV/amu (amu stands for the atomic mass unit) needed for simulations of level populations for principal and orbital quantum numbers in the emitting beryllium ions Be(+3) can be obtained with the help of two-dimensional kinetic codes. The lack of literature data, especially for data resolved in orbital quantum numbers, has instigated us to make numerical calculations with the ARSENY code. A comparison of the results obtained for the one-centre Coulomb problem using an analytic approach and for the two-centre problem using numerical simulations is presented.

Conceptual design of Doppler shift spectroscopy diagnostics for INTF

• Doppler Shift Spectroscopy diagnostics for ITER DNB at Indian Test Facility is conceptualised for neutral beam characterisation. • Modelling of the system suggests that 36 Line of Sights is required for a complete mapping of the beam. • A novel method of deconvolution of beam focusing effect in the total width is performed. • The error in divergence estimation of the 7 mrad focused divergent beam is less than 10%. INTF (Indian Test Facility) is a negative hydrogen ion source based neutral beam test facility to characterise 100 keV,60 A Diagnostic Neutral Beam (DNB), conceptualised for ITER. Several diagnostics are under development to monitor and characterise the performance of ion source and the beam properties. Doppler Shift Spectroscopy (DSS) diagnostics shall be used to estimate the beam divergence, beam inhomogeneity and the stripping losses of the extracted H − ion beam. In this work, the conceptualisation of the DSS diagnostics and the performance evaluation of the proposed system is presented. A forward model is developed to predict the signal strength and signal to noise ratio for various beam operation scenarios and for different optical setups. The model also estimates the expected error in the line width analysis carried for estimating the beam divergence. To reduce the error in the estimated beam divergence, a study on the error propagation was carried out by considering a range of viewing angles, different types of light collection systems and optical instruments. An optimum viewing angle, the light collection system and the instrumentation is chosen accordingly. An endoscopic design concept for each LOS has been adopted and the mechanical assembly of the same is presented in this work. The present work also reports that for a focused divergent beam, using conventional methods of line width analysis might lead large errors and impacts the beam divergence measurements obtained by DSS. A suitable algorithm has been developed to deconvolve the beam focusing spectral width contribution, thereby improving the preciseness of the beam divergence estimation.

Numerical Considerations for Neutral Beam Spectroscopy Based Diagnostics in the Stellarator TJ-II

Two neutral-beam based diagnostic techniques are numerically evaluated for the stellarator TJ-II. The evaluation considers the beam from a dedicated diagnostic neutral beam injector that provides a 5 ms pulse of hydrogen accelerated to 30 keV as well as the light throughput of a dual purpose optical system that views the beam as it traverses the microwave, or neutral beam, heated plasmas of this magnetic confinement device. In the first instance, in which the implementation of the beam emission spectroscopy technique is considered for characterizing medium to long wavelength plasma turbulence, detailed estimates are made to determine the Balmer Hα light intensity reaching avalanche photodiode modules. In the second instance, similar detailed estimates are made for the spectrograph-based experimental set-up used for the Motional Stark Emission technique that has been successfully employed to determine the magnitude and direction of the internal magnetic field in TJ-II plasmas. In addition, optical measurements made to evaluate beam energy and composition are described. Finally, estimates and measurements are compared and discussed in order to complete this work.

Design and analysis of TWIN source extraction system grids with indigenous manufacturing feasibility assessment

Abstract A 3 grid extractor and accelerator system is to be coupled to the two driver RF negative ion source test bed to extract and accelerate H- ion beams up to 50 keV. One of the aims of the TWIN test bed is to characterize and benchmark the optics design of such an accelerator system (1:4 scale) which has been modelled for the 8 driver diagnostic neutral beam negative ion source. A cooling scheme based on analysis and indigenous manufacturing assessment has been selected. In order to enable indigenous manufacturing of embedded cooling channel of such an accelerator a route of vacuum brazing has been considered to close the water cooling channels of the 3 grid segments as against the conventional route of 1 mm thick electrodeposited layer of copper. It will be an attempt to replace copper electro-deposition which has limited availability across the globe. The optimal geometrical requirements for establishing brazing to close the water cooling channels has been successfully realized and validated experimentally by subjecting the developed prototype braze coupon under high heat flux facility at IPR. The selected cooling scheme choice has then been utilized on a strip model (Grid segment) to perform thermo-mechanical analysis under operating load conditions to study thermal profile, stresses, out of plane deformations and aperture displacements (misalignment).