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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 127 records · Page 7
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

EVs@Scale: NextGen Profiles EVSE Characterization 2025

As part of the U.S. DOE EVs@Scale consortium, the Next-Generation Profiles (NextGen Profiles [NGP]) project presents analysis and results from the characterization of high-power conductive and wireless charging infrastructure. High Power Charging equipment is capable of recharging electric vehicle traction batteries at power levels of 200KW and above. Electric Vehicle Service Equipment (EVSE) characterization involves testing over a wide range of DC charging currents and voltages during nominal and off-nominal conditions. This testing allows for a better understanding of the impact that high-power charging will have on the electric grid. A common set of standard test plans, procedures, and data requirements were applied to the characterization in this document with minor updates and improvements. This report covers all conductive characterization activities performed between October 2024 and September 2025 on the Delta Electronics 350KW Electric Vehicle Charging System, consisting of power cabinet model EIDN-U350KTA01 and dispenser model EIDD-U350SSUUAEG-350.Key Findings include: Output regulation, Efficiency and power factor, Load management, Grid Resilience, Smart Charge Management (SCM) performance, Thermal control system performance, Multi-port simultaneous charging performance, and Selected performance comparisons with other EVSEs characterized in the NextGen Profiles project. Hot and cold temperature testing was not conducted on the Delta 350KW due to laboratory limitations. Future research could include continued testing the Delta hardware under off-nominal temperature conditions including multi-port/multi-session simultaneous charge testing, in addition to collecting data on other high-power conductive chargers to augment.

25 ENERGY STORAGE↗
DOE OSTI2024

Development of a Light-Trapping, Planar-Cavity Receiver for Enclosed Solar Particle Heating

Concentrating solar thermal power (CSP) technology development has recently focused on high efficiency power cycles and chemical reactions that require high operating temperatures. An increase in receiver operating temperatures relative to current commercial CSP technology is necessary to support more efficient, high temperature power cycles or thermochemical processes. Solar receivers operating with heat transfer media temperatures >700 degrees C face various challenges including thermal performance, scalability, thermal-mechanical issues, and receiver service life. In addition, heat transfer media selection for high-temperature processes has been moving towards inert solid particles in Gen3 CSP, and reactive solid media and/or gases in solar thermochemical processes. To overcome the shortcomings and limitations of conventional designs for molten salt or particle receivers and receiver reactors, we introduce a unique light-trapping, planar cavity receiver (LTPCR) configuration and will present the current development progresses to demonstrate receiver feasibility through modeling, testing, and prototype demonstration.

ENGINEERING,SOLAR ENERGY↗
DOE OSTI2021

Forecasting Solar-Thermal Systems Performance under Transient Operation Using a Data-Driven Machine Learning Approach Based on the Deep Operator Network Architecture

Modeling and prediction of the dynamic behavior of thermal systems operating under intermittent energy input and variable load requirements represent one of the greatest challenges in the development of efficient and reliable renewable-based power generation technologies. In this work, a data-driven machine learning modeling framework was developed based on a modified version of the Deep Operator Network architecture where the time coordinate in the trunk net is replaced with historical data of the predicting quantity. The modeling framework can be used to accurately predict the performance of renewable-based energy conversion technologies including wind- and solar-based power plants. This novel framework was applied on a solar-thermal system that consists of a solar collection loop using a flat plate collector, a power generation loop comprising an Organic Rankine Cycle, and a thermal energy storage tank connecting both loops. Variable solar irradiance, air temperature, and power load profiles were used by the Deep Operator Network to predict the State-of-Charge and the efficiency of the thermal system for several days. The results were compared with the State-of-Charge and efficiency functions calculated using a physics-based model. For a simple operation scenario, characterized by a clear sky solar irradiance profile and constant load, the standard deviation in the State-of-Charge prediction by Deep Operator Network is below 0.9% during a seven-day prediction time horizon. For the most realistic operation scenario that considers real solar irradiance and a rough load profile, the maximum standard deviation in the predictions for the State-of-Charge and efficiency are below 6.8% and 2.5%, respectively. A comparison between Deep Operator Network and Long Short Term Memory network was also performed. In general, both networks predict very well the State-of-Charge for different data density conditions; however, a higher accuracy, with a standard deviation below 2.0%, is obtained by the Deep Operator Network during three and half days using sparser training data of 20-minute points. The same accuracy for the State-of-Charge prediction with the Long Short Term Memory network is achieved only for 14 h. Average standard deviations for the State-of-Charge prediction of 1.1% with the Deep Operator Network and 1.5% with the Long Short Term Memory network are obtained for a four-day prediction time using a denser training data of 5-minute points.

DeepONet↗
DOE OSTI2020

Experimental Analysis of Salt Hydrate Latent Heat Thermal Energy Storage System With Porous Aluminum Fabric and Salt Hydrate as Phase Change Material With Enhanced Stability and Supercooling

Phase change materials (PCMs), especially salt hydrates possess high volumetric energy storage capacity in their transition temperature range. These materials are used in applications where it is necessary to store thermal energy due to temporary load shift between demand and availability. Thus, possible applications are HVAC, recovery of waste heat, and defense thermal management. Despite salt hydrates potential, the practical feasibility of latent heat storage with salt hydrates is limited due to low power rating, supercooling, phase segregation, and long-term stability. Its low power rating and long-term stability limits its application in most applications. This work experimentally validates the stability and thermal performance of a compact heat exchanger charged with salt hydrate during melting and freezing. The compact heat exchanger was designed with fins on both the heat transfer fluid (HTF) and salt hydrate PCM side. The thermal performance of the latent heat thermal energy storage system (LHTESS) was evaluated for various operating conditions. The results show that LHTESS could achieve an average heat transfer coefficient of 124 and 87 W/(m2 K) during melting and solidification, respectively. The stability of the system in suppressing supercooling was validated over 800 cycles with nucleating agent and active homogenous nucleation techniques. The supercooling was reduced to 3 °C with zinc hydroxyl nitrate as nucleating agent and less than 1 °C with the active homogenous nucleation technique. The LHTESS showed less than 6% degradation in energy storage capacity over 800 cycles.

42 ENGINEERING↗
DOE OSTI2025

HOLISTIC ENERGY EFFICIENCY ANALYSIS OF ELECTRIFIED OFF-HIGHWAY MATERIAL HANDLER: FROM DRIVE CYCLE CHARACTERIZATION TO POWERTRAIN, HYDRAULIC, AND THERMAL SYSTEM PERFORMANCE

Three complexities surrounding the operation and testing of hybrid electric, heavy-duty nonroad machines have been addressed experimentally and using 1D simulation. Their resolutions have been intertwined with the development of a prototype machine that was proven to reduce fuel consumption in excess of 20%. A real-world drive cycle that leveraged hydraulic cylinder position was developed and utilized to ensure accurate reproduction of hydraulic work between the baseline and hybrid machines, while simultaneously maintaining less than 5% RMS error in position for main load handling functions. The newly developed, machine-specific drive cycle also contributed towards making equivalent comparisons in energy consumption between machine types through composite performance metrics that were extrapolated over a typical shift duration. Lastly, this work addressed thermal management energy consumption, a topic of increasing popularity when discussing electrified vehicles, by proposing a 1.4% energy savings through special mechanization and control of cooling system components.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2021

Critical review and future prospects for desiccant coated heat exchangers: Materials, design, and manufacturing

Solid desiccant dehumidification is a promising alternative to vapor compression-based air-dehumidification to reduce energy consumption and improve air quality. Desiccant coated heat exchanger (DCHE), as one type of solid desiccant dehumidification system, can improve system performance and efficiency. The thermal performance and moisture removal capability of the DCHE greatly influence its dehumidification performance.The present work aims to critically analyze the designs, materials, and manufacturing methods of heat exchangers used for solid desiccant coating and look into recent developments in regular heat exchangers, potentially deployed as a substrate for DCHE applications. A comprehensive literature review of publications regarding solid desiccant materials, heat exchangers, manufacturing and coating methods, binder materials, and the performance of heat exchangers has been developed. Alternative heat exchangers are described as better options than fin and tube heat exchangers that have been considered thus far for DCHE applications. Additionally, the heat exchanger's manufacturing process and materials over their thermal and mass exchange performance have been analyzed. Despite the widespread use of fin and tube heat exchangers for solid desiccant coating, recent developments in heat exchanger design, and related fields such as manufacturing methods and materials, open the possibilities for their application in solid desiccant dehumidification systems. Lastly, the authors provide their outlook on possible developments of DCHE technology, aiming to increase systems' energy and dehumidification performance.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Highly Integrated Wide Bandgap Power Module for Next Generation Plug-In Vehicles (Final Report)

Wide bandgap devices are key enablers for high power density traction inverters. A highly integrated wide bandgap (WBG) power module enables higher temperature operation, higher inverter efficiency and overall smaller die area with the same power delivery. However, it requires careful design of the power module to take advantage of all the superior material properties that silicon carbide (SiC) provides over conventional silicon (Si) Insulated Gate Bipolar Transistor (IGBT) based design. This project developed an efficient and densely packed SiC power module for an automotive traction inverter application. Extensive study was performed to select the best performing SiC die considering a wide range of temperature variation, suitability to integrate into target packaging, robust body diode performance and overall high electrical efficiency. Multiple design ideas were explored to achieve lower stray inductance for both power loop and signal loop, uniform current distribution, compact form factor, and very high thermal performance. The final power module package includes all six inverter switches in the same module (six-pack) with die sintered at both bottom and top surfaces utilizing high performance substrate to achieve high electrical and thermal performance. Two power module variants were developed using 900 V and 1200 V devices for operating at two different high voltage levels (> 600 V HV battery). Both power modules were comprehensively characterized, and high efficiency operation of the inverter was confirmed through analysis. Finally, a complete functional inverter was built with the 1200V power modules using other essential components (HV capacitors, gate driver board, controller board, current sensor, connectors etc.) and tested using GM’s standard test procedure. There are several challenges associated with adopting WBG devices for high voltage operation. In order to assess and mitigate those challenges, GM and subrecipients of this project have conducted multiple detailed studies. This includes phase current reconstruction using integrated Rogowski coil, device junction temperature estimation using on-state gate resistance, modeling and testing the effect of high voltage and fast switching on motor insulation and bearings, partial discharge inception voltage measurement under different environmental conditions. Findings of all these studies are summarized in this report.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2025

Design, Fabrication and On-Sun Performance Evaluation of SiC Receiver Feature Specimens for CST Applications Using Additively Manufactured SiC Materials

Increasing operating temperatures of solar receivers is paramount to the efficiency of concentrated solar thermal (CST) and solar power (CSP) systems. Successful development of CST systems to generate heat for industrial applications requires significant increase in temperature capability and techno-economically viability of the receiver systems. Supported by an award from the Solar Technology Office (SETO), US Department of Energy (DOE), GE Aerospace Research in collaboration with Heliogen Holdings Inc and Sandia National Lab, is engaged in the development of ultra-High Operating Temperature SiC-matrix Solar Thermal Air Receiver (HOTSSTAR) enabled by additive manufacturing. The program objective is to demonstrate SiC receiver with air exit temperatures up to 1100 oC and high thermal efficiencies. We report design, fabrication and on-sun test results of SiC components of a prototype 50kW (thermal) HOTSSTAR module. The receiver module architecture is based on a radial airflow design and consists of a series of radial SiC receiver sectors organized around a SiC center absorber. The SiC components are fabricated using binder-jet printed SiC followed by melt-infiltration reaction bonding process. To enhance the reliability and to minimize the risk of cracking damage of SiC test articles in thermal gradient and thermal shock environment of the application, the components were laminated with GE’s MI SiC-SiC CMC. Following extensive design and lab test analyses, selected SiC component designs are tested at Heliogen Lancaster Solar field under highly concentrated solar fluxes around 2000 suns to assess the thermal performance characteristics under realistic field conditions. We report on the test results and compare the thermal performances of different HOTSSTAR SiC absorbers. Finally, we discuss fabrication and initial assembly of a 50kW prototype test module in preparation of on-sun field tests to assess the performance of our final design.

CST, CSP, high temperature, air receiver, SiC, add↗
DOE OSTI2025

Thermal Optimization and Experimental Demonstration of a Silicon Carbide, Half-Bridge Power Module

This paper describes modeling and experimental work to design and demonstrate a silicon carbide (SiC), single-side-cooled power module. Two SiC metal-oxide-semiconductor field-effect transistors (MOSFET) were used for each switch position and packaged on a metalized ceramic substrate. Thermal modeling was first conducted to optimize the module packaging to minimize junction-to-fluid thermal resistance and device temperature variations. This procedure identified the optimal device placement and baseplate thickness to maximize thermal performance. A heat exchanger - incorporating impinging jets of water-ethylene glycol - was designed to cool the module's baseplate to minimize thermal resistance and pumping power. The heat exchanger used relatively low fluid velocities (<1.5 m/s) to minimize erosion-corrosion effects and relatively large fluid channel sizes (>=1 mm) to prevent clogging. The power module concept was fabricated, and experiments were conducted to measure its thermal performance. Direct current was used to power the module devices, and junction temperatures were measured via device temperature-sensitive parameters. The experimental results were found to be in good agreement with model predictions (within 2%) and yielded junction-to-fluid thermal resistance values as low as about 15 mm2 K/W at relatively low pumping power values. The results demonstrate the improved performance associated with jet impingement cooling and represent an improvement over existing channel-flow-type cold plates, which can enable improvements to power density and reliability.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Thermal Management for Planar Package Power Electronics (CRADA Final Report)

The National Renewable Energy Laboratory (NREL) and John Deere Electronic Solutions (JDES) collaborated to develop and evaluate computer models and simulations related to the thermal performance of semiconductor device packaging for an inverter of an off-road vehicle ("Semiconductor Packaging"). The objective of the research was for NREL and JDES to develop a two or three-dimensional computer-aided design model of the Semiconductor Packaging ("Computer Model") for thermal performance evaluation in a simulation. The project developed computer models of a Semiconductor Package of silicon-carbide semiconductor devices with appropriate thermal dissipation via one or more of the following thermal features: a double-sided planar cooling configuration, an air-cooled configuration, a liquid-cooled configuration for off-road inverter applications in a relevant simulated operating environment. It is noted that surface area and prototype product embodiment consisting of air-cooled and liquid-cooled configurations may and may not be in direct contact with power semiconductor chips. The idea was to explore and develop packaging and thermal management technology for power semiconductors that was most effective in the performance yet had least burden in overall product cost for a given application.

33 ADVANCED PROPULSION SYSTEMS↗
DOE OSTI2025

Design, fabrication, simulation, and testing of additively manufactured lattice-based copper heat sinks

Here, this study investigates the potential advantages of lattice structure-based bound metal material extrusion (MEX) 3D printing for fabricating high-performance copper heat sinks. Copper powder-filled polymer filaments, with a copper content of > 90 wt.%, were developed specifically for the bound metal MEX 3D printing process. Three types of structures—planar, strut, and surface lattices—were 3D printed to facilitate efficient heat transfer pathways within the heat sinks. Subsequent post-processing steps, including polymer removal and sintering, were performed to achieve dense copper parts. Hot isostatic pressing was further employed to enhance the sintered density from 93 to 98%. Finite element analysis (FEA) simulations were conducted to assess the heat transfer efficiency of the designs, and heat transfer experiments were performed using a custom setup to validate the simulation results. Additionally, this research explores the use of extended hold times during pre-sintering and a reduced atmosphere to enhance the %IACS values (electrical conductivity) and thermal performance of the bound metal MEX 3D printed copper heat sinks. The investigation combines experimental analysis, including simulations and heat transfer experiments, to gain insights into the structure-material property relationships and optimize the thermal performance of the printed heat sinks.

Ajjarapu, Kameswara Pavan Kumar [Oak Ridge Nationa↗
DOE OSTI2023

Hydrocarbon-based membranes cost-effectively manage species transport and increase performance in thermally regenerative batteries

Low-temperature heat (T<130°C) can be utilized by thermally regenerative batteries (TRBs) for power production, allowing the thermal energy to be converted to storable chemical potential energy. However, TRBs suffer from high ohmic losses and ammonia crossover, which has slowed their development. In this study, we examined how the use of six different membranes influenced TRB performance, determined the most influential membrane parameters, and identified promising membrane candidates that cost-effectively increase TRB performance. Of the six membranes examined, an inexpensive, hydrocarbon CEM (Selemion CMVN) had low ammonia crossover without compromising resistance, resulting in good performance across all metrics studied. A thin anion exchange membrane (Sustainion, 50 microns) showed a high peak power density of 82 mW cm –2 due to low resistance, but the average power density and energy density were low due to high ammonia flux. Full discharge curves using Selemion CMVN provided an average power density of 26 ± 7 mW cm –2 with an energy density of 2.9 Wh L –1 , which were large improvements on previous TRBs. A techno-economic analysis showed that Selemion CMVN had the lowest levelized cost of storage ($410 per MWh) at an applied current density of 50 mA cm –2 .

25 ENERGY STORAGE↗
DOE OSTI2021

Influence of the concentration ratio on the thermal and economic performance of parabolic trough collectors

The thermal and economic performance of parabolic trough collectors (PTCs) and PTCs with double glass envelope (DGE-PTCs) are analyzed in this work. A model including thermal and optical effects is developed to evaluate the efficiency of vacuum and air-filled DGE-PTCs, while an economic model based on two commercial PTCs (SkyTrough and Ultimate Trough collectors) was developed to assess the economic performance. The efficiency and thermal output per unit cost of the proposed DGE-PTCs are analyzed as a function of the concentration ratio and are respectively compared with the thermal and economic performance of traditional and commercial PTCs. The optimum concentration ratio for maximum thermal performance varies from 11.0 to 23.3 for operation temperatures (T HTF ) between 100 degrees C and 400 degrees C, while the optimum concentration ratio for maximum economic performance ranges between 28.9 and 33.2 for the SkyTrough and between 40.0 and 43.8 for the Ultimate Trough collector designs. Finally, the DGE-PTCs present higher thermal and economic performance at high operating temperatures, which presents a valuable opportunity for implementation in new PTC designs pursuing higher operating temperatures to achieve superior thermal cycle efficiencies.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2023

Next Generation of Architectural Precast Insulated Wall Panels

Off-site building envelope construction or prefabrication has many benefits including fewer construction defects, fewer onsite workers, shorter onsite construction time, and less onsite waste. The off-site building construction approach with greatest market success to date is precast concrete. However, precast production needs to develop new technologies to capture a larger share of the construction market. More specifically, architectural precast insulated wall panels would be more widely used if they were lighter, had a shorter production time, and had higher thermal performance. This report summarizes the technologies that Oak Ridge National Laboratory, the Precast/Prestressed Concrete Institute, and the University of Tennessee developed so that the next generation of architectural precast insulated wall panels are 50% lighter, 50% faster to produce, and/or have two times higher thermal performance.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2026

Metal additively manufactured wavy fin cold-plate architecture for improved thermal-hydraulic performance

Rapid growth in artificial intelligence and data center workloads demands high-performance liquid cooling to manage increasing chip power. This study presents two metal-additive-manufactured cold plates with sinusoidal fins, constant-amplitude wavy fins and linearly variable-amplitude wavy fins and compares them against metal-additive-manufactured straight fins using experiments conducted at 1 kW heat dissipation as well as high-fidelity 3D conjugate computational fluid dynamic simulations. The cold plates were printed in AlSi10Mg material and underwent design using a Python-automated workflow prior to manufacture and testing. The experiments show that wavy fins reduce the normalized thermal resistance by 35 to 45 % at water flow rates from 1 to 4 LPM. At a fixed 20 kPa pressure drop, the variable-waviness design lowered peak surface temperature by 9 °C and thermal resistance by 51 %, while edge-channel maldistribution in the constant wavy fin design limited gains. A thermal resistance breakdown revealed that 55–63 % of the total thermal resistance in wavy designs comes from base heat conduction, 27–33 % from fin heat conduction, and 9–13 % from fin heat convection, indicating the need to address conduction bottlenecks. Parametric sweeps identify a 3 mm fin pitch as optimal, and that horizontal inlet/outlet manifolds further reduce pressure drop by 30–60 % and thermal resistance by 9–16 % relative to vertical inlet-outlet manifolds. The results yield comprehensive guidelines for fin geometry, manifold alignment, material selection and additive-manufacturing constraints to realize high-performance liquid-cooled cold plates for power-dense electronics.

3d printing↗
DOE OSTI2021

Experimental Study on Flow Behavior and Heat Transfer Enhancement With Distinct Dimpled Gas Turbine Blade Internal Cooling Channel

Abstract The study presents the investigation on heat transfer distribution along a gas turbine blade internal cooling channel. Six different cases were considered in this study, using the smooth surface channel as a baseline. Three different dimples depth-to-diameter ratios with 0.1, 0.25, and 0.50 were considered. Different combinations of partial spherical and leaf dimples were also studied with the Reynolds numbers of 6,000, 20,000, 30,000, 40,000, and 50,000. In addition to the experimental investigation, the numerical study was conducted using a large eddy simulation (LES) to validate the data. It was found that the highest depth-to-diameter ratio showed the highest heat transfer rate. However, the deepest dimpled channel shows the highest pressure drop, which affects the overall thermal performance of the cooling channel. The results showed that the leaf dimpled surface is the best cooling channel based on the highest Reynolds number's heat transfer enhancement and friction factor. However, at the lowest Reynolds number, partial spherical dimples with a 0.25 depth-to-diameter ratio showed the highest thermal performance.

Energy & Fuels↗
DOE OSTI2022

Multi-cell, triple pane, vacuum insulated glazing

A novel Triple Pane Vacuum Insulated Glazing (TPVIG) architecture consisting of three panes of glass separated by two offset grids is described. The grids are made of frit-coated fibers fused with the glass panes in a vacuum to create many independent hermetic cells. Unlike traditional VIGs, which are separated by support pillars, these cells significantly increase the redundancy in sealing, and the additional bonds formed by the grid lines reduce the stresses on the edge bonds thereby increasing VIG reliability. A numerical thermal analysis was conducted to determine the thermal performance of the VIG and suggested U-values below 0.5 W/m 2 -K (greater than R=11.4 hr-ft 2 -°F/Btu) can be obtained. A prototype of the VIG unit consisting of three glass panes (5.7 mm, 1.1 mm and 5.7 mm thick with low-e coating on two surfaces) was fabricated and tested for thermal performance using the hot box method. The experimental center of glass U-value for the VIG was found to be 0.42 W/m 2 K (R=13.2 hr-ft 2 -°F/Btu). Furthermore, this U-value is about four times lower than a typical Argon filled double pane window.

14 SOLAR ENERGY↗
DOE OSTI2024

Development & Experimental Validation of a Generalized Resistance-Capacitance Model for Numerical Simulation of Phase-Change Material Embedded Heat Exchangers

Latent heat thermal energy storage (LHTES) using phase change material (PCM) has attracted increased attention as a viable solution for overcoming the mismatch between energy supply and demand for renewable energy-based systems. PCM-embedded heat exchangers (PCM-HX) have the potential to significantly improve thermal performance due to high storage capacity and low temperature variation during the phase change process. Most models for simulating LHTES heat transfer use Computational Fluid Dynamics (CFD) simulations, which have high computational costs resulting from considering the complex and time-dependent physics relevant to PCM-HXs. In this paper, a Generalized Resistance Capacitance-based Model (GRCM) was developed to predict the thermal performance of arbitrary PCM-HXs in a computationally efficient manner without compromising modeling accuracy. The GRCM is exercised for three case studies: (i) verification for a single-slabbed finned PCM-HX, (ii) verification and validation for a copper foam/paraffin composite PCM-HX, and (iii) validation for a straight tube annular finned PCM-HX. The copper foam PCM-HX uses an electric heater at the top of HX, while the other two configurations utilize water as heat transfer fluid. For the single-slabbed finned PCM-HX melting case, the mean deviation in average PCM temperature predicted by the GRCM compared to the CFD model was between 0.56 – 0.73 K, with maximum temperature deviation of 2.68 K. For the HTF outlet temperature, the validation results showed that GRCM prediction matches very well with experimental data, with mean temperature deviation of 0.24 K during melting case, while for solidification case was 0.34 K. These results showcase the GRCM’s capability for accurately reproducing the thermal characteristics of PCM-HXs with considerably lower computational effort.

42 ENGINEERING↗