Temperature Jump Research Articles

Homogeneous Crystal Nucleation in Poly (butylene succinate-ran-butylene adipate): Challenging the Nuclei-Transfer Step in Tammann's Method.

The kinetics of homogeneous crystal nucleation and the stability of nuclei were analyzed for a random butylene succinate/butylene adipate copolymer (PBSA), employing Tammann's two-stage crystal nuclei development method, with a systematic variation of the condition of nuclei transfer from the nucleation to the growth stage. Nuclei formation is fastest at around 0 °C, which is about 50 K higher than the glass transition temperature and begins after only a few seconds. Due to the high nuclei number, spherulitic growth of lamellae is suppressed. In contrast, numerous μm-sized birefringent objects are detected after melt-crystallization at high supercooling, which, at the nanometer-scale, appear composed of short lamellae with a thickness of a few nanometers only. Regarding the stability of nuclei generated at -30 °C for 100 s, it was found that the largest nuclei of the size-distribution survive temperature jumps of close to 80 K above their formation temperature. The critical transfer-heating rate to suppress the reorganization of isothermally formed nuclei as well as the formation of additional nuclei during heating increases with the growth temperature at temperatures lower than the maximum of the crystallization rate. This observation highlights the importance of careful selection of the transfer-heating rate and nuclei development temperature in Tammann's experiment for evaluation of the nucleation kinetics.

Thermal-Gas-Elastic Coupling Modeling and Performance Analysis of Foil Cylindrical gas Film Seal Considering Speed Slip, Temperature Jump and Shaft Misalignment

Abstract The Compliant foil cylindrical gas film seal is an advanced sealing technology designed for high-speed and high-temperature conditions in a jet engine. Its design involves using a compliant foil to create a cylindrical sealing surface, achieving adaptive sealing in environments with high pressure differences and rotational speeds. For high-speed and high-temperature operation, a speed slip flow model was established by considering film slip flow, wall temperature jump, foil deformation, and gas viscosity-temperature thermal effects. The variations in the lubrication performance of the foil cylindrical gas film seal with changes in shaft misalignment directions, misalignment angles, and operating parameters were investigated. The speed slip leads to a decrease in gas film lift and an increase in leakage. The wall temperature jump phenomenon caused by speed slip leads to a 2.56% decrease in film temperature. The shaft misalignment angles on the high-pressure and low-pressure sides have different impacts on the flow field, with film pressure and temperature differing by 66.78% and 11.19%, respectively.

Effect of wettability and surface roughness on flow and heat transfer characteristics in nanochannels

The flow and heat transfer processes of liquid argon within nanochannels with random roughness are investigated using the molecular dynamics method. This study explores the effects of surface roughness and wettability on flow and heat transfer performance. The results indicate that both surface roughness and wettability significantly influence temperature jumps, velocity slip, flow resistance, and temperature distribution. Specifically, hydrophilic surfaces can reduce temperature jumps and velocity slip due to their enhanced ability to adsorb liquid atoms, which effectively improves heat transfer while simultaneously increasing flow resistance. The fractal dimension D characterizes the surface roughness, which decreases as D increases. Additionally, both the Nusselt number and drag coefficient decrease with increasing D. In this study, we investigate cases where D ranges from 2.5 to 2.9, with D = 2.5 representing the highest roughness, and the smooth channel corresponding to the lowest roughness. For hydrophilic nanochannels at D = 2.5, the Nusselt number and drag coefficient increased by factor of 2.2 times and 5.2 times compared to smooth channels, respectively. For hydrophobic nanochannels at D = 2.5, the Nusselt number and drag coefficient increased by a factor of 4.5 times and 29.1 times compared to smooth surface channels, respectively. Considering both flow and heat transfer performances, the best comprehensive performance is achieved with D = 2.8 for channels with hydrophilic surfaces and D = 2.6 for channels with hydrophobic surfaces. This work systematically investigates the coupled effects of random roughness and wettability on the flow and heat transfer characteristics in nanochannels, providing new theoretical insights for optimizing nanochannel design.

Photophoresis of a moderately large high-viscosity droplet in slip mode

Purpose of research. To obtain analytical expressions that allow calculating the strength and velocity of a moderately large, highly viscous droplet, taking into account the direct contribution of the evaporation coefficient, linear corrections by the Knudsen number and the reactive effect of a plane wave moving in the field of mono-chromatic radiationMethods. Methods of perturbation theory, gas kinetic methods, mathematical methods for solving linear partial differential equations with variable coefficients (the system of Stokes equations, Laplace and Poisson equations) were used.Results. In a quasi-stationary approximation, a theoretical description of the photophoretic motion of a moderately large evaporating highly viscous spherical droplet (there is no circulation of matter inside the droplet and interfacial surface tension forces) in a viscous binary gas mixture is carried out. A velocity-linearized system of Navi-Stokes equations and heat and mass transfer was solved. Expressions are obtained for the fields of mass velocity, pressure, temperature and the relative numerical concentration of the first component. The strength and speed of photophoresis of a highly viscous droplet was determined by integrating a stress tensor over the surface of the particle. Under boundary conditions on the surface of a highly viscous droplet, linear corrections in terms of the Knudsen number (isothermal, thermal and diffusion slips, temperature and concentration jumps, as well as sliding due to temperature inhomogeneity along the curved surface of the particle), the reactive effect and the contribution of the direct influence of the evaporation coefficient were taken into account. The contributions to the obtained formulas for the photophoresis of a moderately large highly viscous droplet are analyzed and the preliminary transitions to the results known in the literature (moderately large and large solid particles of spherical shape) are considered Conclusion. The obtained formulas based on the hydrodynamic method allow us to evaluate the effect of the direct contribution of the evaporation coefficient and linear corrections by the Knudsen number on the strength and speed of photophoresis of a moderately large evaporating highly viscous droplet in a binary gas mixture.

Sloshing cold fronts in galaxy cluster Abell 2566

This paper presents properties of the intracluster medium (ICM) in the environment of a cool core cluster Abell 2566 (redshift z= 0.08247) based on the analysis of 20 ks Chandra X-ray data. 2D imaging analysis of the Chandra data from this cluster revealed spiral structures in the morphology of X-ray emission from within the central 109 kpc formed due to gas sloshing. This analysis also witness sharp edges in the surface brightness distribution along the south-east and north-west of the X-ray peaks at 41.6 kpc and 77.4 kpc, respectively. Spectral analysis of 0.5 – 7 keV X-ray photons along these discontinuities exhibited sharp temperature jumps from 2.3 to 3.1 keV and 1.8 to 2.8 keV, respectively, with consistency in the pressure profiles, implying their association with cold fronts due to gas sloshing of the gas. Further confirmation for such an association was provided by the deprojected broken power-law density function fit to the surface brightness distribution along these wedge shaped sectorial regions. This study also witness an offset of 4.6′′(6.8 kpc) between the BCG and the X-ray peak, and interaction of the BCG with a sub-system in the central region, pointing towards the origin of the spiral structure due to a minor merger.

Chemical reaction, slip effects and non-linear thermal radiation on unsteady MHD Jeffreys nanofluid flow over a stretching sheet

“The boundary layer flow past the stretching surface by the velocity slip and the temperature jumping boundary situations is the imperative type of the flow and temperature transports happening in a number of engineering and industrial applications. Keeping in this mind, the magnetohydrodynamic (MHD) flow and temperature transport of the Jeffreys nanoliquid past a stretching sheet by the non-uniform temperature source and/or sink is explored in the current investigation. The governing scheme of the partial differential equations represents the prescribed problem and is condensed into the non-linear ordinary differential equations with the help of similarity transformations. The revised non-dimensional equations are solved computationally making use of the Runge-Kutta-Fehlberg 45 order method and the shooting method. The results are comparing by the published work for some limiting cases and they are examined to the outstanding agreements. The impacts of all flow significant parameters are traced in terms of the tables and graphical profiles. This is established that, both initial and second order velocity slip parameters trim downs the thickness of momentum boundary layers and therefore decreases the velocity as a results of these one might found the increases in the thermal boundary layer.” The boundary layer thickness and the fluid velocity increases with increase in Deborah number.

Finite Element Modeling of Crystallization with Temperature Jump to Improve Cryopreservation of Fish Germ Cells

This article is devoted to the further development of a viable technology for low-temperature cryopreservation of reproductive cells of sturgeon fish using acoustic–mechanical fields and intelligent control of the freezing process. Before vitrification begins, the piezoactuator acts on a mixture of cryoprotectant and reproductive cells. This promotes intensive mixing of the cryoprotector and its diffusion through the cell membrane. When vitrification is carried out directly, a phase transition phenomenon is observed, accompanied by crystal formation. This article presents a new mathematical model describing this process as developed by the authors. The corresponding boundary conditions are formulated. Numerical experiments were carried out using the finite element method. It has been established that during vitrification without the use of a cryoprotectant, a sharp temperature jump is observed at the front of the crystalline formation boundary. The use of a cryoprotectant leads to a slowdown in the process of crystal formation, that is, to a weakening of the effect of one of the most important cryoprotective factors. The comparison with full-scale experiments showed qualitative agreement with the experimental results, which indicates the adequacy of the proposed model. The results obtained can be used in the future during the vitrification process and the evaluation of the quality of cryofreezing. The application of a new methodological approach to methods of long-term preservation at low temperatures of the genetic and reproductive material of hydrobionts using acoustic and mechanical effects and an intelligent control module opens up great opportunities for the creation of new cost-effective biotechnologies that make it possible to make the transition to a new type of aquatic farms, increase the stability of aquaculture, in general, to make environmental protection measures to save rare and endangered species more effective.

Synthesis of thermo-responsive polymer gels composed of star-shaped block copolymers by copper-catalyzed living radical polymerization and click reaction

ABSTRACT In recent times, there has been a significant surge in research interest surrounding thermo-responsive water-soluble polyacrylamides, primarily due to their intriguing capability to undergo significant solubility changes in water. These polymers exhibit the remarkable ability to shift from a soluble to an insoluble state in response to temperature variations. The capacity of these polymers to dynamically respond to temperature changes opens up exciting avenues for designing smart materials with tunable properties, amplifying their utility across a spectrum of scientific and technological applications. Researchers have been particularly captivated by the potential applications of thermo-responsive water-soluble polyacrylamides in diverse fields such as drug delivery, gene carriers, tissue engineering, sensors, catalysis, and chromatography separation. This study reports the construction and functionalization of polymer gels consisting of a polymer network of polyacrylamide derivatives with nano-sized structural units. Specifically, thermo-responsive polymer gels were synthesized by combining well-defined star-shaped polymers composed of polyacrylamide derivatives with a multifunctional initiator and linking method through a self-accelerating click reaction. The polymerization system employed a highly living approach, resulting in polymer chains characterized by narrow molecular weight distributions. The method’s high functionality facilitated the synthesis of a temperature-responsive block copolymer gel composed of N-isopropyl acrylamide (NIPA) and N-ethyl acrylamide (NEAA). The resulting polymer gel, comprising star-shaped block copolymers of NIPA and NEAA, showcases smooth volume changes with temperature jumps.

Photolipid excitation triggers depolarizing optocapacitive currents and action potentials

Optically-induced changes in membrane capacitance may regulate neuronal activity without requiring genetic modifications. Previously, they mainly relied on sudden temperature jumps due to light absorption by membrane-associated nanomaterials or water. Yet, nanomaterial targeting or the required high infrared light intensities obstruct broad applicability. Now, we propose a very versatile approach: photolipids (azobenzene-containing diacylglycerols) mediate light-triggered cellular de- or hyperpolarization. As planar bilayer experiments show, the respective currents emerge from millisecond-timescale changes in bilayer capacitance. UV light changes photolipid conformation, which awards embedding plasma membranes with increased capacitance and evokes depolarizing currents. They open voltage-gated sodium channels in cells, generating action potentials. Blue light reduces the area per photolipid, decreasing membrane capacitance and eliciting hyperpolarization. If present, mechanosensitive channels respond to the increased mechanical membrane tension, generating large depolarizing currents that elicit action potentials. Membrane self-insertion of administered photolipids and focused illumination allows cell excitation with high spatiotemporal control.

Non-fourier phonon heat transport in graphene nanoribbon field effect transistors based on modified phonon hydrodynamic lattice Boltzmann method

Graphene, with its exceptional thermal conductivity and electron mobility, is widely recognized as a potential candidate for next-generation transistor materials. Despite the lack of pronounced phonon hydrodynamic phenomena at room temperature in graphene materials, momentum-conserving phonon normal scattering predominantly drives phonon hydrodynamic transport. Current methodologies, including the Single Mode Relaxation Time (SMRT) approximation and Fourier's law, inadequately capture phonon transport within the ballistic and hydrodynamic regimes of graphene. In light of these limitations, this study introduces a Non-gray phonon hydrodynamic lattice Boltzmann method in combination with the Temperature Jump Boundary Condition to provide a more accurate depiction of phonon heat transport in graphene nanoribbon field-effect transistors (GNRFETs) spanning these regimes. The findings reveal that our proposed model significantly mitigates heat transfer errors in GNRFETs, primarily driven by ballistic transport compared to the SMRT model. This suggests that the model's applicability extends beyond scenarios dominated by phonon hydrodynamics and is effective even in cases dominated by ballistic transport. In conclusion, our study emphasizes the impact of hydrodynamic transport on heat transfer in GNRFETs and underscores the importance of adjusting parameters related to the heating zone width and specular parameter to enhance thermal stability.

Kinetics of physical aging of a silicate glass following temperature up- and down-jumps.

In this article, we investigate the structural relaxation of lithium silicate glass during isothermal physical aging by monitoring the temporal evolution of its refractive index and enthalpy following relatively large (10-40 °C) up- and down-jumps in temperature. The Kohlrausch-Williams-Watts function aptly describes the up- and down-jump data when analyzed separately. For temperature down-jumps, the glass exhibits a typical stretched exponential kinetic behavior with the non-exponentiality parameter β < 1, whereas up-jumps show a compressed exponential behavior (β > 1). We analyzed these datasets using the non-exponential and non-linear Tool-Narayanaswamy-Moynihan (TNM) model, aiming to provide a comprehensive description of the primary or α-relaxation of the glass. This model described both up- and down-jump datasets using a single value of β ≤ 1. However, the standard TNM model exhibited a progressively reduced capacity to describe the data for larger temperature jumps, which is likely a manifestation of the temperature dependence of the non-exponentiality or non-linearity of the relaxation process. We hypothesize that the compressed exponential relaxation kinetics observed for temperature up-jumps stems from a nucleation-growth-percolation-based evolution on the dynamically mobile regions within the structure, leading to a self-acceleration of the dynamics. On the other hand, temperature down-jumps result in self-retardation, as the slow-relaxing denser regions percolate in the structure to give rise to a stretched exponential behavior.

BioCARS: Synchrotron facility for probing structural dynamics of biological macromolecules.

A major goal in biomedical science is to move beyond static images of proteins and other biological macromolecules to the internal dynamics underlying their function. This level of study is necessary to understand how these molecules work and to engineer new functions and modulators of function. Stemming from a visionary commitment to this problem by Keith Moffat decades ago, a community of structural biologists has now enabled a set of x-ray scattering technologies for observing intramolecular dynamics in biological macromolecules at atomic resolution and over the broad range of timescales over which motions are functionally relevant. Many of these techniques are provided by BioCARS, a cutting-edge synchrotron radiation facility built under Moffat leadership and located at the Advanced Photon Source at Argonne National Laboratory. BioCARS enables experimental studies of molecular dynamics with time resolutions spanning from 100 ps to seconds and provides both time-resolved x-ray crystallography and small- and wide-angle x-ray scattering. Structural changes can be initiated by several methods-UV/Vis pumping with tunable picosecond and nanosecond laser pulses, substrate diffusion, and global perturbations, such as electric field and temperature jumps. Studies of dynamics typically involve subtle perturbations to molecular structures, requiring specialized computational techniques for data processing and interpretation. In this review, we present the challenges in experimental macromolecular dynamics and describe the current state of experimental capabilities at this facility. As Moffat imagined years ago, BioCARS is now positioned to catalyze the scientific community to make fundamental advances in understanding proteins and other complex biological macromolecules.

Double Diffusive Nonlinear Convective MHD Unsteady Slip-Flow Regime in a Rectangular Channel

In the paper, we numerically explored the combined impacts of non-linear thermal and mixed convective unsteady flow in a channel with slip conditions. The flow is caused by a moving flat parallel surface and is also electrically conductive. We analyse the mechanisms of heat, and mass transfer by incorporating temperature and concentration jumps. To simplify the model problem, we apply appropriate similarity transformations, reducing the prevailing problem to a nonlinear coupled ordinary boundary value problem. The transformed problem is solved using the Chebyshev Collocation Approach (CCA). We performed a comparative analysis by comparing the CCA with the literature to verify the accuracy of our approach, and a good agreement is found. In addition, we conducted a comprehensive parametric study to analyze the trends in the solutions obtained. The study reveals that the parameters M, α1, α3, Pr, and Sc have about 20% stronger impact on the nonlinear system compared to the linear system on both surfaces of the horizontal channel.

MONITORING SUMMER DAYTIME AND NIGHTTIME DECADAL TRENDS OF LAND SURFACE TEMPERATURE OVER THE NATIONAL CAPITAL REGION DELHI

Abstract. Urbanization-related growth and development have been recognized as substantial factors in increasing surface temperatures. India's rapid urbanization has exacerbated climate change challenges, particularly the rising Land Surface Temperature (LST) and Urban Heat Island (UHI) phenomena. The study used LST data from the MODerate Resolution Imaging Spectroradiometer (MODIS) to examine decadal variances in LST and diurnal LST variations over the summer months in a study region. We compared the LST values in 2010, 2020, and 2022 with the reference year 2000 by analyzing LST data collected from 2000 to 2022 using geospatial analysis. The study found a significant increase in the LST over a two-decade period, particularly in May and June, with temperature jumps of up to 10 (°C) both during the day and at night. The study also revealed differences in LST patterns between rural and urban regions, with rural areas having a higher daytime LST than urban areas and urban areas witnessing an elevated nighttime LST owing to the UHI impact. Analysis revealed significant differences in LST patterns, with 2020 showing lower surface temperatures due to limited heat released from anthropogenic activities such as industrial operation and vehicular traffic due to the COVID-19 lockdown. However, in the years 2010 and 2022, the study observed a significant increase in LST during the summer months both during the day and at night. These findings provided useful insights for urban development and planning and contribute to the implementation of measures aimed at reducing heat-related risks and improving the well-being of urban residents.

Coupled modeling of combustion and hydrodynamics for a 600 MW Bunsen-type boiler

ABSTRACT Hydrodynamic calculation is considered to be significantly important to ensure the safe operation of boiler during the peak-shaving process. An accurate furnace heat flux distribution is the basis for the accurate hydrodynamic calculation. To investigate the hydrodynamic characteristics of a 600 MW boiler, a coupled model that consists of combustion simulation and hydrodynamic calculation is applied in this study. The numerical simulation could provide the distribution of the furnace heat flux as a preparation for the hydrodynamic calculation. Results show that the calculated value of the hydrodynamic characteristics agrees well with the measured one. The pressure drop differences of the steam system between the calculated and measured values are 0.04, 0.02, 0.13, and 0.05 MPa under 100% boiler maximum continuous rating (BMCR), 75% turbine heat acceptance (THA), 50% BMCR, and 30% BMCR loads, respectively. The relative error of the mass flux distribution increases as operating load decreases, reaching a maximum (7.63%) under 30% BMCR load. For the four loads discussed in this study, the greatest temperature of the working fluid is 681.0 K, while the fin-center temperature jumps from 708.0 to 801.7 K under 100% BMCR load. The present study is intended to improve the method of the hydrodynamic performance calculation, which would benefit the safety operation of boiler during the peak-shaving process.

Importance of the fundamental entropy for determining interfacial thermal resistance temperature jump differences

This work presents a method for calculating the difference in temperature jumps observed at the solid–water and water–solid interfaces when heat is flowing under steady state conditions from a hot to a cold solid separated by an intermediate water phase. The method is based on a hypothesis stating that the entropy flux is maximized where the heat flux is constrained, i.e., at the solid–water interfaces. By focusing on the entropy rather than the heat flux and by maximizing its value vs the magnitude of the temperature jump over the interfaces where the latter is constrained, simple analytical expressions for the jump differences independent of the actual heat flux are established only depending on the absolute temperature of the hot and cold solid. The results show that the temperature jump at the hotter interface, therefore, must be higher than the jump at the colder because of the differences in absolute temperature between the two interfaces, supported by many observations. The results, furthermore, show that the temperature jump asymmetry between the two interfaces should increase with decreasing absolute temperature of the system. The work, therefore, finally indicates that there are two quantities contributing to the magnitude of any temperature jump, the heat and entropy flux. More investigations about their relationship under different conditions are encouraged since the topic is not systematically acknowledged and, therefore, investigated in the literature.

Temporal characteristics of hypersonic flows over a double wedge with Reynolds number

Laminar hypersonic flows at Mach 7.10 with unit Reynolds numbers of 5.2×104, 1.04×105, and 4.14×105 m−1 over a 30°/55° double-wedge configuration were studied to investigate the spatial–temporal characteristics of the flow in a time-accurate manner. Close comparisons were made between previous kinetic and current continuum approaches to test the validity of the continuum assumption, especially considering the presence of large gradients associated with shock–shock and shock–boundary layer interactions, as well as spanwise instabilities. Previous results from direct simulation Monte Carlo, which inherently predicts rarefied effects such as velocity slip and temperature jumps, were found to be in very close agreement with the current work, even for the lowest Reynolds number. The impact of velocity slip and temperature jumps on flow and surface parameters was investigated, and comparisons were made with a no-slip and constant temperature wall model. The temporal and spatial variation of two- and three-dimensional flows were thoroughly investigated using two-dimensional (2D), three-dimensional (3D) periodic sidewall boundary conditions, and a full 3D configuration consistent with existing experimental data. Close comparisons among the 2D and 3D cases were made. The characteristics of 2D periodic oscillations were reported for the moderate Reynolds number case for the first time. The presence of spanwise instabilities, even at a relatively low free stream pressure of about 100 Pa, establishes that the flow field depends on spanwise effects and is fully 3D. High-fidelity numerical schlieren videos captured strong spanwise oscillations for 3D configurations.

A suicidal mechanism for the exquisite temperature sensitivity of TRPV1

The vanilloid receptor TRPV1 is an exquisite nociceptive sensor of noxious heat, but its temperature-sensing mechanism is yet to define. Thermodynamics dictate that this channel must undergo an unusually energetic allosteric transition. Thus, it is of fundamental importance to measure directly the energetics of this transition in order to properly decipher its temperature-sensing mechanism. Previously, using submillisecond temperature jumps and patch-clamp recording, we estimated that the heat activation for TRPV1 opening incurs an enthalpy change on the order of 100 kcal/mol. Although this energy is on a scale unparalleled by other known biological receptors, the generally imperfect allosteric coupling in proteins implies that the actual amount of heat uptake driving the TRPV1 transition could be much larger. In this paper, we apply differential scanning calorimetry to directly monitor the heat flow in TRPV1 that accompanies its temperature-induced conformational transition. Our measurements show that heat invokes robust, complex thermal transitions in TRPV1 that include both channel opening and a partial protein unfolding transition and that these two processes are inherently coupled. Our findings support that irreversible protein unfolding, which is generally thought to be destructive to physiological function, is essential to TRPV1 thermal transduction and, possibly, to other strongly temperature-dependent processes in biology.

Laser ablation behavior of a 2-D C/SiC-Ti3SiC2 composite

When subjected to laser irradiation of different power densities, Ti3SiC2 MAX phase-modified 2-D C/SiC composite experiences various chemical and physical reactions and demonstrates various ablation resistance. An in-situ observation measurement is developed to obtain the instantaneous mesoscopic ablation process for revealing the ablation mechanism. Then scanning electron microscope (SEM) and X-ray energy dispersive spectroscopy (EDS) tests are performed to determine the reaction process. The results show that the Ti3SiC2 MAX phase can effectively prevent laser irradiation into the material at a laser power density below 636.5 W/cm2. The advantage of ablation resistance disappears at a high laser power density of 2546 W/cm2 due to the decomposition and sublimation of SiC and Ti3SiC2. A chart of ablation mechanisms versus laser power density is constructed based on the instantaneous mesoscopic ablation behavior, macro/meso/microscopic ablation morphology, and temperature history. It is also found that there are two forms of "Temperature Jump" phenomena. One is the accelerated temperature rise in the temperature history of the single-irradiation event. The other is the step point in the maximum temperature curve for multiple irradiation events. The mechanisms of the "Temperature Jump" phenomena are explained based on the interface energy balance.

Design and manufacture of a proof-of-concept resorption heat pump using ammonia-salt chemisorption reactions

Using the Large Temperature Jump (LTJ) experimental technique, alongside a review of the literature, sodium bromide (NaBr) and manganese chloride (MnCl2) have been identified as a suitable working pair with ammonia refrigerant for a proof-of-concept resorption heat pump system. LTJ tests using a tube-side and shell-side unit cell reactor (sorption heat exchanger), show that the experimentally obtained equilibrium lines for adsorption and desorption of sodium bromide are: ΔHADS = 30,102.5 J/mol; ΔSADS = 207.7 J/(mol·K); ΔHDES = 30,216.4 J/mol; and ΔSDES = 206.8 J/(mol·K). Using a semi-empirical model, the NaBr composite salt (salt impregnated in expanded natural graphite (ENG)) has been characterised for use as a low temperature salt in a resorption heat pump, with manganese chloride as the high-temperature salt. The model constants, A and n, for adsorption are 1 and 3, and for desorption are 5 and 4 respectively for NaBr. Manganese chloride data has been previously reported (Hinmers et al., 2022). With an appreciation of the reaction dynamics and behaviour of the NaBr and MnCl2 composite salts, a proof-of-concept resorption system has been designed and manufactured. The reactor design, alongside the overall experimental rig design (including data acquisition system) is reported. Initial filling and flushing tests show the success of the data acquisition and control system, and thus the overall suitability of the proof of-concept system for investigations into the coupled nature of ammonia salt reactions for a resorption heat pump application.