Shock-flame Interaction Research Articles

Numerical simulation of deflagration-to-detonation transition via shock–multiple flame kernels interactions

The deflagration-to-detonation transition via the interaction of a weak shock with a series of discrete laminar flames is analyzed computationally based on the unsteady reactive Navier–Stokes equations with one-step Arrhenius chemistry. For comparison, simulations with the Euler equations are also performed. The numerical setup aims to mimic an array of laminar flames ignited at different spark times, artificially inducing chemical activity to stimulate the coupling between the gas dynamics and the chemical energy release for the deflagration-to-detonation transition. The interaction of the weak shock with the first cylindrical flame demonstrates a very good agreement with the results in the literature and that a single weak shock–flame interaction is insufficient to cause a prompt DDT. However, a high degree of Richtmyer–Meshkov instabilities induced by repetitive shock–flame and shock–boundary interactions generate turbulence that accelerates the flame surface, referred to as the flame brush, until eventually a hot spot ignition in the unreacted material develops into a multi-headed detonation wave. In the absence of physical diffusion in the Euler simulation, the enhanced burning rate of the turbulent flame brush is suppressed. Nevertheless, the intense flow fluctuations generated by the interactions of shocks, boundary and flames create the conditions under which a deflagration-to-detonation transition can potentially occur at later times. A parametric study is also reported in this paper to assess the influence of various physical parameters on the transition event and to explore scaling relationships among these parameters.

Direct Numerical Simulation of the Richtmyer–Meshkov Instability in Reactive and Nonreactive Flows

ABSTRACT Uncontrolled hydrogen/air explosions pose a central problem in nuclear and process plant safety research. The Richtmyer–Meshkov Instability (RMI) can be an important contributing factor to flame acceleration and subsequently the deflagration-to-detonation transition. In this context, the RMI is caused by the interaction of a sharp pressure gradient, generated by a shock wave and the density gradient at a flame surface. This interaction leads to the production of baroclinic torque at the flame surface, which causes flame wrinkling. For this work, compressible direct numerical simulations of a shock wave, interacting with a perturbed statistically planar flame in a premixed medium, are conducted. After the first interaction with the flame, a second instance of shock–flame interaction (re-shock) is observed, caused by the reflection of the shock wave from an adiabatic wall on the right-hand side of the domain. The influence of the chemical reaction, shock strength, as well as initial flame surface disturbance on the flame surface area and mixing width , are investigated. It is found that the chemical reaction has a large impact on the development of and , as it partly smoothens emerging wrinkled structures on the flame surface for the present thermochemistry. The maximum reached is hereby reduced by about compared to cases without chemical reaction. A comparison of the development of over time with predictions from an analytical model shows good agreement for the linear portion of the instability (short time frame after shock interaction). The model then fails to predict the decrease of in the non-linear part of the model, due to the smoothing effects of the chemical reaction. The influence of the initial flame disturbance on the development of the flame surface area and mixing width shows a strong dependence on the selected disturbance wavenumber . The maximum achievable flame surface area is inversely proportional to in the investigated range. Increasing the shock Mach number and therefore increasing the pressure gradient showed a strong impact on the development of the RMI. After the first shock interaction, numerous fresh gas funnels are created, reaching into the burned gas. Therefore, when the re-shock interaction occurs, the shock will interact with an increased and more irregular flame surface. In addition, the flame thickness is reduced by about upon each shock interaction, due to flame compression and increase in the pressure level from the shock wave. Both effects will lead to distinct spikes in the baroclinic torque production over time upon flame interaction with the re-shock and result in a strong increase of and .

Three-dimensional inert and reactive shock-interface interactions: statistical flow characterisations

ABSTRACTThree-dimensional inert and reactive shock-interface interactions are simulated by solving NS equation with ninth-order WENO scheme. An initial planar shock wave with Mach number 1.7 accelerates a single mode and finite thickness interface with initial wavelength 4 mm and amplitude 0.4 mm from the reactant composed of C2H4+3O2+4N2. Then the transmitting shock branch is reflected at the end boundary to be the first reflected shock which disturbs the flame generating a transmitting shock branch and a reflected shock branch across the interface. This reflected shock branch reflects at the end boundary and accelerates the interface again. The simulation includes successive shock-interface interactions and a decaying period. Temporal and regional characterisations are presented, including Mach number, sound speed, kinetic energy and enstrophy. Furthermore, statistical characterisations of velocity and vorticity are conducted both in spatial space and wavenumber space. Based on these characterisations, there is a discussion of effects on vorticity generation, in terms of baroclinic effect, strain effect and physical viscous effect. In addition, comparisons between inert and reactive shock-flame interactions are made to examine the contribution of reaction.

TimeScale Analysis, Numerical Simulation and Validation of Flame Acceleration, and DDT in Hydrogen–Air Mixtures

ABSTRACT Flame Acceleration (FA) and Deflagration to Detonation Transition (DDT) are known risks in scenarios involving accidental release and combustion of hydrogen in nuclear reactors. In the present work, chemical timescale and Borghi diagram analysis of hydrogen combustion have been presented. Based on these, a map of the flame propagation in the GraVent shock tube channel has been constructed; and it has been established that the propagation corresponds to the flamelet regime. Subsequently, CFD framework applicable to the flamelet regime such as the geometric approach with turbulent flame closure has been utilized to study deflagrations, FA and DDT. Such methods allow for the computation of pressure transients and flame propagation characteristics with a relatively coarse grid, thereby enabling a balance between computational time and accuracy. Moreover, specific sub-models based on Lewis number and tuned to lean combustion at high pressures have been implemented to further improve the accuracy of the numerical results. All numerical work has been carried out using the open-source numerical platform OpenFOAM. Several numerical simulations with uniform and transversely stratified initial distribution have been carried out and validated with experimental data. In the stratified case, an asymmetric flame front has been observed and is identified to be a key parameter leading to strong FA. Detailed analysis shows that several pressure pulses and shock complexes are formed upstream of the flame. The ensuing shock–flame interaction augments the flame speed ultimately resulting in DDT. Comparative simulations with uniform distribution also show strong FA but DDT does not take place.

Scalar characterisations of three-dimensional shock-flame interactions: similarity and inhomogeneity

ABSTRACTThree-dimensional shock-flame interactions are simulated by the ninth-order WENO scheme to study the characterisations of scalar under Richtmyer-Meshkov instability (RMI) with reaction. Initially, a planar incident shock with Ma = 1.7 accelerates the single-mode diffusive flame interface with initial wavelength 4 mm and amplitude 0.4 mm from the reactant C2H4+3O2+4N2 medium with temperature 293 K and pressure 13.3 kPa; then the transmitting shock branch during incident shock-flame interaction is reflected at the end boundary to form a reflected shock which disturbs the flame interface again. The reflected shock-flame interaction will form transmitting and reflecting shock branches where the reflecting branch reflects at the end boundary and accelerates the flame interface again. During successive interactions between flame interface and shocks, a large range of flow is generated. Physical processes in the flame interface are examined related to the evolution of reactant density and internal energy density, including convection, molecule diffusion, reaction, pressure-dilatation, and heat conduction. Similarity in scalars and velocity is examined in both spatial and spectral spaces and inhomogeneity related to similarity is provided.

Flame evolution in shock-accelerated flow under different reactive gas mixture gradients.

The interaction between a planar shock wave and a spherical flame is studied numerically for an ethylene-oxygen-nitrogen gas mixture. Influences of different initial reactive gas mixture gradients on the shock-flame interaction are investigated by using high-resolution computational simulations. The results show that the different reactive gas mixture gradients can greatly affect the flame evolution in shock accelerated flow. A detonation only emerges in the homogenous reactive gas mixture case, but a distinct shock bifurcation can be found in the inhomogeneous cases where the leftward reflected shock wave propagates in a reverse flow with a high transverse velocity gradient in the inhomogeneous cases. Also, the flame volume and heat release rate increase when the distribution of the reactive gas mixture is uniform or with a positive gradient in this paper, but decrease when the distribution of the reactive gas mixture is with a negative gradient, however, the ratio of unburned to burned regions in the flame zone shows just the opposite trends. Furthermore, the factors affecting the vorticity generation are also analyzed. It is found that the compression term has a relatively stronger influence on the vorticity generation in all the three cases except the period before the reflected shock wave impinges on the distorted flame in the homogeneous case, wherein the baroclinic effect dominates the vorticity generation in the flame zone.

Numerical simulation and validation of flame acceleration and DDT in hydrogen air mixtures

Combustion of hydrogen can take place in different modes such as laminar flames, slow and fast deflagrations and detonations. As these modes have widely varying propagation mechanisms, modeling the transition from one to the other presents a challenging task. This involves implementation of different sub-models and methods for turbulence-chemistry interaction, flame acceleration and shock propagation. In the present work, a unified numerical framework based on OpenFOAM has been evolved to simulate such phenomena with a specific emphasis on the Deflagration to Detonation Transition (DDT) in hydrogen-air mixtures. The approach is primarily based on the transport equation for the reaction progress variable. Different sub-models have been implemented to capture turbulence chemistry interaction and heat release due to autoignition. The choice of sub-models has been decided based on its applicability to lean hydrogen mixtures at high pressures and is relevant in the context of the present study. Simulations have been carried out in a two dimensional rectangular channel based on the GraVent experimental facility. Numerical results obtained from the simulations have been validated with the experimental data. Specific focus has been placed on identifying the flame propagation mechanisms in smooth and obstructed channels with stratified initial distribution. In a smooth channel with stratified distribution, it is observed that the flame surface area increases along the propagation direction, thereby enhancing the energy release rate and is identified to be the key parameter leading to strong flame acceleration. When obstacles are introduced, the increase in burning rate due to turbulence induced by the obstacles is partly negated by the hindrance to the unburned gases feeding the flame. The net effect of these competing factors leads to higher flame acceleration and propagation mechanism is identified to be in the fast deflagration regime. Further analysis shows that several pressure pulses and shock complexes are formed in the obstacle section. The ensuing decoupled shock-flame interaction augments the flame speed until the flame coalesces with a strong shock ahead of it and propagates as a single unit. At this point, a sharp increase in propagation speed is observed thus completing the DDT process. Subsequent propagation takes place at a uniform speed into the unburned mixture.

Detonation initiation from shock and material interface interactions in hydrogen-air mixtures

A numerical study was conducted to explore the mechanisms of detonation initiation in a stoichiometric hydrogen-air mixture resulting from the interaction between a Mach 2.8 shock and a perturbed material interface. The simulations used a high-order compressible numerical method for fluid dynamics with both detailed and simplified chemical-diffusive models. Three material interfaces were considered: no interface, a perturbed planar flame, and a perturbed helium interface. The case with no interface did not evolve into a detonation. The case with the flame produced a series of additional shock-flame and shock-shock interactions. The shock-shock interactions produced a series of contact surfaces and sliplines with increasing temperature. Hot spots eventually formed along these sliplines and a detonation was initiated shortly thereafter through a reactivity gradient mechanism. The overall process of detonation initiation was similar for both detailed and simplified chemical-diffusive models. Only the fine details, such as the precise time and location of the hot spots, were different. This indicates that simplified chemical-diffusive models are adequate to describe the initiation of detonations in the present configuration. The processes that ignited the detonation were also similar in the case where the flame was replaced with a helium interface. Helium has a similar acoustic impedance to the products and produced similar wave refraction patterns. Thus, the primary effect of the flame is to facilitate the shock-shock interactions that produce hot spots and initiate the detonation. The chemical energy released by the flame has a secondary influence.

フレームジェット対向噴射による管内へのデトネーション起爆

Detonation transition was experimentally investigated using flame jetting through the orifice of a small sub-chamber, which was equipped on the side wall near the closed end of the main channel (square inner closs section, 50 mm on a side) filled with a stoichiometric hydrogen-oxygen mixture at an initial pressure of 80 kPa. The number of sub-chambers and orifice diameters were changed as 1, 2, 4 (called as FJ1, FJ2, FJ4, respectively) and 3, 5, 7 mm, respectively, and the facing flame jets were collided with each other in FJ2 and FJ4. Two regimes of detonation transition were observed: (i) deflagration-to-detonation transition (DDT) accompanied by flame acceleration process and (ii) direction initiation of a detonation near the flame jetting section. The flame propagation distance required for detonation transition was one-half to one-third for regime (i) compared to single-spark ignition without flame jet, and below one-sixth for regime (ii). Except for the case of regime (ii), observed for an orifice diameter of 5 or 7 mm of FJ4, the detonation transition distance had no significant effect on the types of flame jetting and orifice diameters. Time-resolved schlieren recordings showed that the choked jet of combustion products drove the shock wave preceding the flame front, and induced multi-dimensional flame motion and repeated shock-flame interactions in the confinement. These behaviors enhanced flame velocity at the ignition end by a factor of 4 to 7 in FJ1 and FJ2, compared to single-spark ignition. The effect of these enhanced flame velocities on DDT distances was consistent with the semi-empirical model of flame acceleration process in a smooth tube. The schlieren recordings and pressure measurements at the closed end indicated that the possible factors for the initiation of detonation in regime (ii) were the mixing of reacted and unreacted gas induced by the repeated strong shock-flame interaction and the hot spot formed by shock-shock interaction driven by the facing flame jetting.

Shock transition to detonation in channels with obstacles

Multidimensional numerical simulations of an unconfined, homogeneous, chemically reactive gas were used to study interactions leading to deflagration-to-detonation transition (DDT). The configuration studied was a long rectangular channel with regularly spaced obstacles containing a stoichiometric mixture of ethylene and oxygen, initially at atmospheric conditions and ignited in a corner with a small flame. The compressible reactive Navier–Stokes equations were solved by a high-order numerical algorithm on a locally adapting mesh. The initial laminar flame develops into a turbulent flame with the creation of shocks, shock–flame interactions, shock–boundary layer interactions, and a host of fluid and chemical-fluid instabilities. The final result may be eventual deflagration-to-detonation transition (DDT). Here two types of simulations are described, one with DDT occurring in a gradient of reactivity, which is common in the channels with higher obstacles, and another in which DDT arises from energy focusing as shocks converge. For the latter case, the rate of energy deposition necessary to initiate a detonation in the unburned gas is analyzed using a control volume analysis.

Effect of decreasing blockage ratio on DDT in small channels with obstacles

Multidimensional numerical simulations of an unconfined, homogeneous, chemically reactive gas were used to catalog interactions leading to the deflagration-to-detonation transition (DDT). The configuration studied was an infinitely long rectangular channel with regularly spaced obstacles containing a stoichiometric mixture of ethylene and oxygen, initially at atmospheric conditions and ignited in a corner with a small flame. The channel height is kept constant at 3200 µm and obstacle heights varied from 2560 µm to 160 µm to decrease the blockage ratio (br) from 0.8 to 0.05. The compressible reactive Navier–Stokes equations were solved by a high-order numerical algorithm on a locally adapting grid. The initially laminar flame develops into a turbulent flame with the creation of shocks, shock-flame interactions, shock-boundary layer interactions, a host of fluid and chemical-fluid instabilities, and DDT. Several different DDT mechanisms are observed as the br is reduced. For br in the range of 0.5–0.35, the shocks in the unburned material diffract over the obstacles and reflect against the channel wall, forming Mach stems that increase in strength with every obstacle traversed. Eventually, the Mach stem strength is sufficient for the unburned mixture to detonate after it reflects from an obstacle. For br outside of this range, DDT may occur either through Mach-stem reflection or through direct initiation due to shock focusing. Stochasticity of the turbulence leading to DDT in channels with low br is considered.

Simultaneous OH-PLIF and schlieren imaging of flame acceleration in an obstacle-laden channel

Flame acceleration in stoichiometric H2/O2 at 12 and 25 kPa initial pressure in an obstacle-laden square cross-section channel was studied experimentally using planar laser-induced fluorescence imaging of hydroxyl radicals (OH-PLIF) and simultaneous high-speed schlieren imaging. Results were obtained resolving the explosion front structure as it develops immediately after ignition as a slow-flame to the eventual formation of a shock-flame complex in the fast-flame regime. The images provide a novel level of detail and allow for the determination of the effects of turbulence-flame and shock-flame interaction. In the slow-flame regime, vortex shedding off obstacle edges occurs over long time-scales, vortices are convected downstream and turbulent combustion takes place in the obstacle wakes. The fast-flame regime is marked by the presence of compression waves (and shock waves) which interact with the flame and cause macroscopic deformation of the flame and small-scale wrinkling due to Richtmyer-Meshkov instability. A quasi-steady fast-flame is characterized by the close proximity of the precursor shock and the turbulent flame. The flow-field that governs the flame shape is established impulsively by the precursor shock. Shock-flame interactions lead to flame front perturbations on both small and large scales. The OH-PLIF technique makes it possible to discern the flame front from other density interfaces that appear in the complex fast-flame structure observed in schlieren images and also eliminates the line-of-sight integration limitation.

Numerical simulations of the process of multiple shock–flame interactions

Based on a weighted essentially nonoscillatory scheme, the multiple interactions of a flame interface with an incident shock wave and its reshock waves are numerically simulated by solving the compressible reactive Navier–Stokes equations with a single-step Arrhenius chemical reaction. The two-dimensional sinusoidally perturbed premixed flames with different initial perturbed amplitudes are used to investigate the effect of the initial perturbation on the flame evolutions. The results show that the development of the flame interface is directly affected by the initial perturbed amplitudes before the passages of reshock waves, and the perturbation development is mainly controlled by the Richtmyer–Meshkov instability (RMI). After the successive impacts of multiple reshock waves, the chemical reaction accelerates the consumption of reactants and leads to a gradual disappearance of the initial perturbed information. The perturbation developments in frozen flows with the same initial interface as those in reactive flows are also demonstrated. Comparisons of results between the reactive and frozen flows show that a chemical reaction changes the perturbation pattern of the flame interface by decreasing the density gradient, thereby weakening the baroclinic torque in the flame mixing region, and therefore plays a dominant role after the passage of reshock waves.

Combustion wave propagation through a bank of cross-flow cylinders

Combustion wave propagation through a bank of 12.7mm diameter cylinders is investigated in a 76.2mm tall, 25.4mm wide channel using high-speed schlieren photography. Two cylinder geometries (“staggered” and “inline”) were tested with 50% channel area blockage. The staggered geometry was also tested with 67% blockage. Tests were carried out with hydrogen–air at atmospheric pressure. Flame propagation is highlighted by an initial flame acceleration phase driven by turbulent burning in the cylinder wakes. This is followed by quasi-steady flame propagation characterized by shock-flame interactions. Flame acceleration measured in the staggered and inline cylinder geometry, for the same blockage, was found to be similar despite the different flame pathways. In the fast-flame regime, the quasi-steady flame velocity was also found to be very similar. In the composition range where detonation initiation and failure was observed, often referred to as the quasi-detonation regime, the average velocity was significantly higher in the staggered cylinder geometry due to the higher frequency of detonation initiation.

LES of flame acceleration and DDT in hydrogen–air mixture using artificially thickened flame approach and detailed chemical kinetics

A large eddy simulation is performed to study the deflagration to detonation transition phenomenon in an obstructed channel containing premixed stoichiometric hydrogen–air mixture. Two-dimensional filtered reactive Navier–Stokes equations are solved utilizing the artificially thickened flame approach (ATF) for modeling sub-grid scale combustion. To include the effect of induction time, a 27-step detailed mechanism is utilized along with an in situ adaptive tabulation (ISAT) method to reduce the computational cost due to the detailed chemistry. The results show that in the slow flame propagation regime, the flame–vortex interaction and the resulting flame folding and wrinkling are the main mechanisms for the increase of the flame surface and consequently acceleration of the flame. Furthermore, at high speed, the major mechanisms responsible for flame propagation are repeated reflected shock–flame interactions and the resulting baroclinic vorticity. These interactions intensify the rate of heat release and maintain the turbulence and flame speed at high level. During the flame acceleration, it is seen that the turbulent flame enters the ‘thickened reaction zones’ regime. Therefore, it is necessary to utilize the chemistry based combustion model with detailed chemical kinetics to properly capture the salient features of the fast deflagration propagation.

A compressible-LEM turbulent combustion subgrid model for assessing gaseous explosion hazards

A turbulent combustion subgrid model, inspired by the Linear Eddy Model for Large Eddy Simulation (LEM-LES), is developed to study highly compressible and reactive flows involving very rapid transients in pressure and energy. The model is intended to be a one-dimensional treatment of a diffusion-reaction system within a multi-dimensional LES cell. The goal is to reduce the expense of solving a complete multi-dimensional problem through Direct Numerical Simulation (DNS) while preserving micro-scale hotspots and their physical effects on ignition. The current approach features a Lagrangian description of fluid particles on the subgrid for increased accuracy. Recently, the model approach has been verified for various fundamental 1-D test cases, including inert mixing, constant volume ignition, shock tube problems and laminar flame propagation. In the current study, the model is extended to treat turbulent methane-air flames in one-dimension. Also, a 1-D piston-driven laminar shock–flame interaction and its subsequent transition to detonation is modelled. Results confirm that both laminar and turbulent flame speeds are reproduced when compared against 1D computations of the Navier–Stokes equations (1D-NS) and experiments, respectively. Furthermore, the model offers a good prediction for detonation initiation in the presence of shock waves when compared to high and low-resolution 1D-NS simulations. Finally, the model is demonstrated to reproduce the correct detonation structures, velocities, and instability behaviour when compared to theory and the 1D-NS computations.

Three-Dimensional Numerical Simulations of Spherical Flame Evolutions in Shock and Reshock Accelerated Flows

The three-dimensional spherical flame evolutions induced by incident and reflected shock waves in a rectangular shock tube are numerically simulated using the compressible reactive Navier–Stokes equations with a single-step Arrhenius chemical reaction. Four cases, including variable parameters of flame size and number, shock wave strength, and mixture reactivity, are considered in order to investigate the effects of these parameters on the flame evolutions and detonation onsets. The three-dimensional visualized results and the time-dependent integral and statistical results for the shock–flame interactions are obtained. The morphology of the flame evolutions for all cases studied shows the severe distortion, expansion, and corrugation of flame disturbed by shock waves, especially by a reflected shock wave. The unstable flame produces the three-dimensional reactive shock bifurcation (RSB) structure, as the flame number, the shock wave strength, or the mixture reactivity increase. Further, detonations can occur in a later stage of flame evolution at the different three-dimensional spatial locations for different cases through the shock–detonation–transition (SDT) mechanism. Unlike the three-dimensional spatial dissimilarities of flame patterns and detonation initiation locations among cases studied, the time-dependent integral and statistical properties of flame developments prior to detonation onset show the more similar behaviors for all cases. During the passage of shock and reshock waves, the spherical flames are compressed and distorted, resulting in the vorticity deposition within flame and the well-mixing between the burned and unburned gases. Physical process dominates the compression phases of the flame evolution. Following the passage of the shock and reshock waves, the well-mixing facilitates the chemical heat release and expands (accelerates) the distorted flame. The chemical process becomes more prominent, especially under the reshock condition. In the flame expansion phases, the baroclinic effect is weakened, and the vortex stretching effect is enhanced with the development of flame. In addition, the well-mixing by the passages of shock waves promotes the chemical reaction of the flame, which in turn burns out the mixing zone of flame and therefore inhibits the mixing.

Pressure-Gain Combustion Using Shock–Flame Interaction

One method of significantly improving the performance of gas turbine engines is to use the thermodynamically more efficient unsteady combustion with pressure rise. In this work, the feasibility of using the interaction of shock waves with a flame to achieve pressure-gain combustion is investigated. A new analytical model is described. The pressure rise and entropy suppression of a single shock–flame interaction event is predicted for the first time. The model is quasi-one dimensional, with the shock wave planar and the flame laminar premixed. Given known initial flowfield and flame geometry, as well as the incident shock Mach number, the model allows the calculation of a fully defined one-dimensional flowfield that is formed at the end of a single shock–flame interaction event. The analytical model is successfully verified using experimental data on methane-oxygen-argon flames. It is found that a single shock–flame interaction event temporally generates a dramatic increase in pressure compared to isobaric combustion with the same unburned gas conditions. The associated increase in temperature remains at a relatively moderate level. Further, combustion entropy rise is significantly reduced through a single shock–flame interaction event.

Effect of multi-bend geometry on deflagration to detonation transition of a hydrocarbon-air mixture in tubes

We present a numerical investigation of gaseous deflagration-to-detonation transition (DDT) triggered by a shock in a multi-bend geometry. The ethylene-air mixture filled rigid tube with obstacles is considered for understanding the effects of complex confinement and initial flame size on DDT. Our calculations show generation of hot spots by flame and strong shock interactions, and flame propagation is either restrained or accelerated due to the wall obstacles of both straight and bent tubes. The effect of initial flame size on DDT in complex confinement geometry is analyzed as well as the hot spot formation on promoting shock–flame interaction, leading to a full detonation.

Scaling Interface Length Increase Rates in Richtmyer–Meshkov Instabilities

The interface area increase produced by large-amplitude wave refraction through an interface that separates fluids with different densities can have important physiochemical consequences, such as a fuel consumption rate increase in the case of a shock–flame interaction. Using the results of numerical simulations along with a scaling analysis, a unified scaling law of the interface length increase was developed applicable to shock and expansion wave refractions and both types of interface orientation with the respect to the incoming wave. To avoid a common difficulty in interface length quantification in the numerical tests, a sinusoidally perturbed interface was generated using gases with different temperatures. It was found that the rate of interface increase correlates almost linearly with the circulation deposited at the interface. When combined with earlier developed models of circulation deposition in Richtmyer–Meshkov instability, the obtained scaling law predicts dependence of interface dynamics on the basic problem parameters.