Hertzian Contact Model Research Articles

Pancreatic cancer metastasis: Adhesion and stiffness

Pancreatic ductal adenocarcinoma (PDAC) cells undergo a semi-epithelial to mesenchymal transition. They express Cadherin proteins characteristic of both normal (E-cadherin) and cancer (N-cadherin) cells. Cadherins are involved in cell-cell adhesion. Additionally, cells must adjust their mechanical properties to undergo metastasis. We use Atomic Force Microscopy (AFM) to characterise the mechanical properties of PDAC cell lines from the primary tumour sites (PANC1, PL45) and from liver (CFPAC1) and lymph node (Hs766T) metastases. AFM measures forces using the optical lever system. To measure their stiffness, cells were probed using a rectangular cantilever with a three-sided pyramidal tip. The Hertz contact model was used to calculate Apparent Young's modulus (E) from the approach curve. The structural damping model was used to calculate the power-law exponent (α) from force curves with logarithmically oscillating contact part. To probe the adhesive properties of the cells, a single cell was attached to functionalised triangular tipless cantilevers, and then pressed against a confluent layer of cells. When the cell-cantilever is retracted, the contact of the attached cell with the cell layer is broken. The detachment exerts force on the cantilever, and this signal is also recorded by and analysed from the retract curve. PANC1 and PL45 cells are stiffer in a confluent layer as compared to single cells. CFPAC1 cells soften in confluent layers, and have lesser adhesion between them as compared to PANC1. CFPAC1 cells also have reduced cell-cell interaction with endothelial cells (EA.hy926) after inhibiting N-cadherin. Thus, N-cadherin inhibition can increase liver metastatic cell lines’ self-interaction and decrease interaction with endothelial cells. While primary tumour cell lines experience mixed mechanical response to surrounding cells, liver metastasis cells are softer and more viscous.

Friction Behavior between Carbon Fiber Plain Weave and Metal Semi-Cylinder Tool

The deformations that occur during composite forming processes are governed by the friction between the fabrics and tooling material on the mesoscopic level. The effect of normal load and multi-plies on the frictional behavior of the carbon plain weave is investigated by simulating the friction between the fabric and metal semi-cylinder tool by using the experimental method. The periodic wavy friction-displacement curve between the metal tool and fabric is caused by the interwoven structure of the fabric. Both the increase in the normal load and the number of layers cause an increase in the real contact area during friction, leading to an increase in the friction force. The real contact area is calculated based on the Hertzian contact model and the self-designed testing method. The friction force values obtained from multiplying the real contact area with shear strength are closely aligned with the measured results.

Particle-based numerical simulation of continuous ice-breaking process by an icebreaker

The continuous ice-breaking capacity of an icebreaker is an important indicator of its efficiency. The ice resistance encountered by an icebreaker has a significant influence on its continuous ice-breaking capacity. In this study, we develop a numerical model based on the moving particle semi-implicit (MPS) method, which is a particle method based on continuum mechanics, for predicting the ice resistance encountered by icebreakers during continuous ice-breaking operations. Before fracture, the ice is assumed to be a linear elastic material, and the maximum tensile stress theory is used as the fracture criterion. A scalar function composed of the first principal stress gradient and the first eigenvector of the stress tensor is introduced to express the relative positions of the new crack and corresponding particle pair. As the hull is represented by polygons and the ice fragments are represented by particles, the collision points between the hull and the ice, i.e., between polygons and particles, is determined using a novel search algorithm that expands a cell linked-list algorithm. The collisions between individual ice fragments and between the hull and an ice fragment are considered using a particle-based model that is a modified form of the Hertz contact model. The proposed algorithm was verified using experimental data obtained from three-point bending tests on model and freshwater ice specimens that were performed by the Korea Research Institute of Ships and Ocean Engineering (KRISO) and Korea Maritime and Ocean University (KMOU), respectively. The verification process revealed that the closer the properties of the ice to the linear elastic properties assumed in the numerical model, the higher the accuracy of the proposed algorithm. The verified algorithm was used to predict the ice resistance encountered by a model icebreaker during a continuous ice-breaking process. A series of convergence and parametric tests were performed for the main parameters of the continuous ice-breaking simulation, and the experimental results obtained by KRISO were used for comparison. The maximum relative errors from experiment were approximately 12% and 30% under free (Fr) and semi-fixed (SF) side boundary conditions, respectively. The proposed numerical algorithm can successfully predict the ice resistance encountered by an icebreaker and the occurrence of near- and far-field fractures during a continuous ice-breaking process.

A flexible pressure sensor with highly customizable sensitivity and linearity via positive design of microhierarchical structures with a hyperelastic model

The tactile pressure sensor is of great significance in flexible electronics, but sensitivity customization over the required working range with high linearity still remains a critical challenge. Despite numerous efforts to achieve high sensitivity and a wide working range, most sensitive microstructures tend to be obtained only by inverting naturally existing templates without rational design based on fundamental contact principles or models for piezoresistive pressure sensors. Here, a positive design strategy with a hyperelastic model and a Hertzian contact model for comparison was proposed to develop a flexible pressure sensor with highly customizable linear sensitivity and linearity, in which the microstructure distribution was precalculated according to the desired requirement prior to fabrication. As a proof of concept, three flexible pressure sensors exhibited sensitivities of 0.7, 1.0, and 1.3 kPa−1 over a linear region of up to 200 kPa, with a low sensitivity error (<5%) and high linearity (~0.99), as expected. Based on the superior electromechanical performance of these sensors, potential applications in physiological signal recognition are demonstrated as well, and such a strategy could shed more light on demand-oriented scenarios, including designable working ranges and linear sensitivity for next-generation wearable devices.

An optimisation analysis of external profile modification of outer raceway of a track needle roller bearing

The stress concentration phenomenon in the outer raceway will greatly influence the life and operational accuracy of track needle roller bearings (TNRBs). A reasonable contact surface profile of the outer raceway can reduce the stress concentration on its external profile. To reduce the stress concentration on the external profile of the outer raceway, a non-ideal Hertzian contact (NIHC) model for describing the interactions between the guide rail and outer raceway is presented by using the NIHC theory. The effects of the fully crowned profile (FCP), partially crowned profile with one curvature centre (PCPO), partially crowned profile with two curvature centres (PCPT), and logarithmic profile (LP) on the stress distribution between the guide rail and outer raceway are studied. Note that the stress concentration phenomenon of the PCPO case, PCPT case, and FCP can be produced. The stress distribution of LP case is more symmetrical and uniform than other cases. The stress distribution of the LP case is smaller than those of other cases. Therefore, the LP is more suitable for the outer raceway of the TNRB. Moreover, this method can be helpful for obtaining a reasonable external profile modification case of the outer raceway of the TNRBs.

Effect of Wrapping Force on the Effective Elastic Behavior of Packed Cylinders

Abstract When cylinders are packed and wrapped by the bands around the surface, the effective elastic behavior in the cross section of the assembly, which is of significance to its stability and integrity, can be controlled by the wrapping force in the band. The wrapping force is transferred to the cylinders through the Hertz contact between each pair of neighboring cylinders, which is validated by the experiments. The Singum model is introduced to study the mechanical behaviors of the packed cylinders with two-dimensional (2D) packing lattices, in which an inner cylinder is simulated by a continuum particle of Singum and the inter-cylinder force is governed by the Hertz contact model so as to derive the effective stress-strain relationship. The wrapping force will produce configurational forces given a displacement variation, which significantly changes the effective stiffness of the packed cylinders. The hexagonal packing exhibits isotropic elasticity whereas the square packing is anisotropic. The efficacy of our model is demonstrated by comparing the closed form elasticity against the numerical simulation and the previous models. The explicit form of elasticity can be used for packing design and quality control of cable construction and installation.

Delamination in GLARE laminates subjected to oblique low velocity impact considering friction

Study of oblique low velocity impact and the subsurface delamination caused in fibre metal laminates is not well reported in literatures. The present paper numerically investigates the oblique low velocity impact behaviour of clamped GLARE plates by a spherical impactor to study the influence of obliquity and coefficient of friction on the impact mechanism and on the extent of interfacial delamination. A three dimensional finite element formulation employing Newmark-β method has been developed for analyzing the oblique contact impact response of GLARE plate where Hertzian contact model is used for the normal component of contact and Mindlin and Deresiewicz theory is used for the tangential component. Results show that besides impactor velocity, obliquity of incidence and the coefficient of friction significantly influence the contact force history, contact duration and the delamination at the interfaces. In addition, the oblique angle also decides the instant and duration of reversal of tangential contact force where increasing obliquity leads to delayed instant and reduced duration of such reversal.

An efficient analytical approach to assess root cause of nonlinear electric vehicle gear whine

Noise, vibration, and harshness (NVH) issues pose considerable challenges for electric vehicle powertrain engineers. Gear vibrations generate an intrusive gear whine noise, with significant impact on the sound quality of electric powertrains. Dynamic transmission error (DTE) is the most quantitative indicator for gear NVH. Backlash, time variable meshing stiffness and damping contribute to DTE. Hence, a better understanding of these excitation sources is essential. A gear tribodynamics model is developed using potential energy method to estimate time variable meshing stiffness (TVMS). A fully analytical time-efficient model is proposed for lubricated contact stiffness based on transitions in the regimes of lubrication. The model accounts for the combined effects of surface elasticity and lubricant stiffness. Film thickness and damping coefficients are transiently updated at each instant during meshing cycle. The predictions from this model are compared with measured results from the literature and predicted results from Hertz contact model. The lubricated contact model successfully shows the contribution of the lubricant stiffness to TVMS and its variations with elasticity and viscosity parameters during meshing cycle. Gear harmonic and super-harmonic resonances are accurately estimated in terms of amplitude, frequencies and stiffness softening nonlinearities. Time history responses and phase-displacement diagrams show good agreement with the gear dynamics response at the main harmonic and second super-harmonic frequencies. The proposed model has a reasonable accuracy, significantly better than those from Hertzian contact models, and is considerably time efficient in comparison to numerical EHL solvers.

Quantification of bush-cricket acoustic trachea mechanics using Atomic Force Microscopy nanoindentation

Derived from the respiratory tracheae, bush-crickets’ acoustic tracheae (or ear canals) are hollow tubes evolved to transmit sounds from the external environment to the interior ear. Due to the location of the ears in the forelegs, the acoustic trachea serves as a structural element that can withstand large stresses during locomotion. In this study, we report a new Atomic Force Microscopy Force Spectroscopy (AFM-FS) approach to quantify the mechanics of taenidia in the bush-cricket Mecopoda elongata. Mechanical properties were examined over the longitudinal axis of hydrated taenidia, by indenting single fibres using precision hyperbolic tips. Analysis of the force-displacement (F-d) extension curves at low strains using the Hertzian contact model showed an Elastic modulus distribution between 13.9 MPa to 26.5 GPa, with a mean of 5.2 ± 7 GPa and median 1.03 GPa. Although chitin is the primary component of stiffness, variation of elasticity in the nanoscale suggests that resilin significantly affects the mechanical properties of single taenidia fibres (38% of total data). For indentations up to 400 nm, an intricate chitin-resilin response was observed, suggesting structural optimization between compliance and rigidity. Finite-element analysis on composite materials demonstrated that the Elastic modulus is sensitive to the percentage of resilin and chitin content, their location and structural configuration.Based on our results, we propose that the distinct moduli of taenidia fibres indicate sophisticated evolution with elasticity playing a key role in optimization. Statement of significanceIn crickets and bush-crickets, the foreleg tracheae have evolved into acoustic canals, which transport sound to the ears located on the tibia of each leg. Tracheae are held open by spiral cuticular micro-fibres called taenidia, which are the primary elements of mechanical reinforcement. We developed an AFM-based method to indent individual taenidia at the nanometre level, to quantify local mechanical properties of the interior acoustic canal of the bush-cricket Mecopoda elongata, a model species in hearing research. Taenidia fibres were immobilized on a hard substrate and the indenter directly approached the epicuticle surface. This is the first characterization of the nano-structure of unfixed tracheal taenidia, and should pave the way for further in vivo mechanical investigations of auditory structures.

Experimental Inter-Modal Targeted Energy Transfer in a cantilever beam undergoing Vibro-impacts

This work experimentally demonstrates inter-modal targeted energy transfer (IMTET) in a cantilever beam system with vibro-impacts. IMTET is known to achieve non-resonant rapid energy transfer from low-to-high frequency structural modes in mechanical systems. While previous works have computationally demonstrated the efficacy of IMTET, the theory and methodology supporting IMTET still lacks experimental verification. To address this task, an experiment is constructed whereby a steel beam is clamped at one end and excited at the other, and steel tips with clearances anchored to a host fixture serve as vibro-impacts (VIs) which induce non-resonant energy redistribution within the modal space of the beam. The system is modeled as an Euler–Bernoulli cantilever beam which is discretized by the finite element method, and the VI forces are simulated by a single-sided dissipative Hertzian contact model. The time-responses, modal dissipation ratios, and characteristic decay times measured in the experiment are compared to the computational models to confirm the validity of the theoretical predictions. It is found for both the experiment and computational model that the VIs transfer energy from low frequency structural modes to high frequency ones which, in turn, results in a substantial reduction in the characteristic decay time and thus confirms the efficacy of IMTET in practice. The diverse potential applications of IMTET in engineering practice are then emphasized.

Hertzian and adhesive plane models of contact of two inhomogeneous elastic bodies

Previous study of contact of power-law graded materials concerned the contact of a rigid body (punch) with an elastic inhomogeneous foundation whose inhomogeneity is characterised by the Young modulus varying with depth as a power function. This paper models Hertzian and adhesive contact of two elastic inhomogeneous power-law graded bodies with different exponents. The problem is governed by an integral equation with two different power kernels. A nonstandard method of Gegenbauer orthogonal polynomials for its solution is proposed. It leads to an infinite system of linear algebraic equations of a special structure. The integral representations of the system coefficients are evaluated, and the properties of the system are studied. It is shown that if the exponents coincide, the infinite system admits a simple exact solution that corresponds to the case when the Young moduli are different but the exponents are the same. Formulas for the length of the contact zone, the pressure distribution and the surface normal displacements of the contacting bodies are obtained in the form convenient for computations. Effects of the mismatch in the Young moduli exponents are studied. A comparative analysis of the Hertzian and adhesive contact models clarifies the effects of the surface energy density on the contact pressure, the contact zone size and the profile of the contacting bodies outside the contact area.

Wind turbine main-bearing lubrication – Part 2: Simulation-based results for a double-row spherical roller main bearing in a 1.5 MW wind turbine

Abstract. This paper is the second in a two-part study on lubrication in wind turbine main bearings. Where Part 1 provided an introductory review of elastohydrodynamic lubrication theory, this paper will apply those ideas to investigate lubrication in the double-row spherical roller main bearing of a 1.5 MW wind turbine. Lubrication is investigated across a “contact conditions dataset” generated by inputting main-bearing applied loads, estimated from hub loads generated using aeroelastic simulation software, into a Hertzian contact model of the main bearing. From the Hertzian model is extracted values of roller load and contact patch dimensions, along with the time rate of change of contact patch dimensions. Also included in the dataset are additional environmental and operational variable values (e.g. wind speeds and shaft rotational speeds). A suitable formula for estimating film thickness within this particular bearing is then identified. Using lubricant properties of a commercially available wind turbine grease, specifically marketed for use in main bearings, an analysis of film thickness across the generated dataset is undertaken. The analysis includes consideration of effects relating to temperature, starvation, grease thickener interactions and possible non-steady effects. Results show that the studied main bearing is at risk of operating under mixed lubrication conditions for a non-negligible proportion of its operational life, indicating that further work is required to better understand lubrication in this context and implications for main-bearing damage and operational lifetimes. Key sensitivities and uncertainties within the analysis are discussed, along with recommendations for future work.

Viscoelastic behavior in discrete element method realized by interparticle Maxwell–Zener model

The discrete element method describes the motion of granular structures numerically. Each particle is considered as a discrete element. Combining springs and dashpot for the normal contact forces, viscoelastic behavior represented by rheological models is realized via a nonlinear Maxwell–Zener model in a dynamic routine. For individual contacts and large particle structures, this model is compared to the Hertzian contact model for elastic behavior and studied with respect to rate dependence and the effect of model parameters.

Measuring the elastic modulus of soft biomaterials using nanoindentation

The measurement of the elastic modulus of soft biomaterials via nanoindentation relies on the accurate determination of the zero-point of the tip-sample interaction on which the depth of penetration into the sample is based. Non-cantilever based nanoindentation systems were originally designed for hard materials, and therefore monitoring the zero-point contact presents a significant challenge for the characterisation of very soft biomaterials. This study investigates the ability of non-cantilever based nanoindentation to differentiate between hydrogels with elastic moduli on the order of single kiloPascals (kPa) using a bespoke soft contact protocol and low flexural stiffness of instrument. Polyethylene glycol (PEG) hydrogels were fabricated as a model system with a range of elastic moduli by varying the polymer concentration and degree of crosslinking. Elastic modulus values were calculated using the Oliver-Pharr method, Hertzian contact model, as well as a viscoelastic model to account for the time-dependent behaviour of the gels. The stiffness measurements were validated by measuring cantilever beams with the equivalent flexural stiffness to that of the PEG hydrogels being tested. The results demonstrated a high repeatability of the measurements, enabling differentiation between hydrogels with elastic moduli in the single kPa to hundreds of kPa range.

Surface-resolved dynamic simulation of charged non-spherical particles

We present a numerical method for simulating the electrostatic interaction of a cluster of charged non-spherical particles as they collide with each other. The boundary element method (BEM) is employed to resolve the highly nonuniform surface charge distribution on individual particles, based on which their electrostatic interactions can be computed. The method of generalized minimum residual (GMRES) incorporated with the fast multipole method (FMM) is adopted to accelerate the electrostatic calculation. The framework is validated through four different cases and is proven to capture the induced higher-order multipole interaction as two particles become very close to each other. This interaction is also shown to be sensitive to the particle geometry, in particular the local curvatures. In addition to the electrostatic interactions, the contact forces and torques are included using the Hertzian contact model to capture the particle collision. Finally, this comprehensive framework is demonstrated by reproducing typical collision outcomes, e.g., sticking and fragmentation, among several non-spherical charged particles.

Discrete Element Modeling of Aeolian-like Morphologies on Comet 67P/Churyumov-Gerasimenko

Context. Even after the Rosetta mission, some of the mechanical parameters of comet 67P/Churyumov-Gerasimenko’s surface material are still not well constrained. They are needed to improve our understanding of cometary activity or for planning sample return procedures. Aims. We discuss the physical process dominating the formation of aeolian-like surface features in the form of moats and wind taillike bedforms around obstacles and investigate the mechanical and geometrical parameters involved. Methods. By applying the discrete element method (DEM) in a low-gravity environment, we numerically simulated the dynamics of the surface layer particles and the particle stream involved in the formation of aeolian-like morphological features. The material is composed of polydisperse spherical particles that consist of a mixture of dust and water ice, with interparticle forces given by the Hertz contact model, cohesion, friction, and rolling friction. We determined a working set of parameters that enables simulations to be reasonably realistic and investigated morphological changes when modifying these parameters. Results. The aeolian-like surface features are reasonably well reproduced using model materials with a tensile strength on the order of 0.1–1 Pa. Stronger materials and obstacles with round shapes impede the formation of a moat and a wind tail. The integrated dust flux required for the formation of moats and wind tails is on the order of 100 kg m−2, which, based on the timescale of morphological changes inferred from Rosetta images, translates to a near-surface particle density on the order of 10−6–10−4 kgm−3. Conclusions. DEM modeling of the aeolian-like surface features reveals complex formation mechanisms that involve both deposition of ejected material and surface erosion. More numerical work and additional in situ measurements or sample return missions are needed to better investigate mechanical parameters of cometary surface material and to understand the mechanics of cometary activity.

A non-smooth quasi-zero-stiffness isolator with displacement constraints

Quasi-zero-stiffness (QZS) mechanism is one of the significant solutions with its distinct advantage to the low-frequency vibration isolation problems in mechanical vibration. However, subject to the limitation of its effective range of very narrow, the strong nonlinearity of the single QZS mechanism under large-amplitude excitation might induce an undesirable large-amplitude vibration or even damage some essential equipment. Therefore, this paper designs a double-layer QZS vibration isolator with displacement constraints to reduce the undesirable large-amplitude vibration. Firstly, the mechanical model of a double-layer QZS vibration isolator with displacement stops is established based on Hertz's contact model (DLQZS-HCM). Subsequently, the incremental harmonic balance method is employed to examine the vibration isolation performance theoretically. The system parameters are then analyzed to explore their influences on the isolation performance. Compared with the double-layer linear isolator (DLL) and double-layer QZS isolator (DLQZS), it is found that the DLQZS-HCM isolator can perform better in both extending the frequency range of vibration isolation and decreasing the peak transmissibility when undergoing large-amplitude excitation. Finally, in order to further enhance the isolation performance at low-frequency levels, feedback control is applied to the DLQZS-HCM isolator. The obtained results reveal that the increasing displacement feedback gain can significantly broaden the vibration-isolation range of the DLQZS-HCM isolator in the frequency area tending to zero.

Modeling of material removal based on multi-scale contact in cylindrical polishing

In this paper, the material removal and the surface roughness in the cylindrical polishing with a soft pad and free abrasives are investigated theoretically and experimentally. Existing our studies have suggested that there is different contact deformation at dimension scales of millimeter, micrometer and nanometer. On that basis, the material removal model is proposed by integrating the contact at different scales in accordance with the Hertz contact, the Greenwood and Williamson's model (G-W model) of rough contact and the single grain's cutting depth. Furthermore, a model of surface roughness is built based on the idea that more materials are removed at the peak on the workpiece's surface, whereas few materials are removed at the valley. The polishing experiments and simulation of cylindrical AISI 52100 steel using the polyurethane polishing pad and the free abrasives of aluminum oxide powder were performed through the Taguchi orthogonal tests, which indicated that the simulation results were well consistent with the experimental results. Under the optimal conditions, the material removal rate (MRR) of 0.40 μm/min was achieved, and the surface roughness Ra was reduced from 104.90 to 20.22 nm after the polishing for 12 min. The contributions of the loading force, the abrasives concentration and the grain size on the MRR and the surface roughness are investigated in accordance with the variance and the level average response, and their reasons are discussed at different scales. It is revealed that the influences of loading force and grain size are significantly different at multi-scale. Furthermore, the parameters related to the contact (e.g., nominal contact area, average contact gap and single grain's cutting depth) under different conditions are studied.

Model-based estimation of rail roughness from axle box acceleration

Monitoring rail roughness in the railway network allows directing grinding actions to where they are needed to reduce rolling noise and large wheel/rail forces. To be able to measure rail roughness on a large scale, indirect measurements onboard railway vehicles have to be carried out. Existing methods use either axle box acceleration (ABA) or under-coach noise measurements to monitor the rail roughness indirectly. The two main challenges with rail roughness estimation from vibroacoustic signals measured onboard vehicles are to separate wheel and rail roughness and to take into account varying track dynamics in the railway network. Both questions have not yet been addressed sufficiently.In this paper, an enhanced method for estimating rail roughness from ABA is presented. In contrast to all existing methods in the literature, the presented method operates in the time domain. A time-domain method has the advantage that the spatial variations of roughness become visible and paves the way for the detection of localized defects such as squats or deteriorated welds. The method is based on a previously developed time-domain model for high-frequency wheel/rail interaction and estimates the time series of the roughness from the time series of ABA. In a first step, the time series of the contact force is calculated from the axle box acceleration using a Least Mean Square algorithm for source identification. In a second step, the combined wheel/rail roughness is obtained from the contact force based on a non-linear Hertzian contact model and a convolutional approach to determine wheel and rail displacement. Separation of wheel and rail roughness is possible by cycle-averaging the contact force over a distance corresponding to the wheel perimeter and performing the second step separately for the part of the contact force originating from the wheel and the rail roughness, respectively.The method was tested for simulated ABA obtained from measured wheel and rail roughness. In the relevant wavelength range from 0.5 m to 5 mm, the rail roughness could be estimated with good accuracy for known track dynamics. Overall, deviations in 1/3-octave bands between estimated and actual roughness were below 1 dB. Only for low rail roughness, higher deviations of less than 2.6 dB occurred around the pinned-pinned resonance frequency. Uncertainties in the track parameters affect the roughness estimation, where the most critical parameter is the rail pad stiffness. A deviation of 20% in rail pad stiffness leads to deviations in the rail roughness of up to 3.5 dB in single 1/3-octave bands. The results illustrate the need to extend the method for the simultaneous extraction of track parameters and roughness from measured axle box acceleration.

A triboelectric nanogenerator sensor based on phononic crystal structures for smart buildings and transportation systems

Many buildings and equipment are frequently disturbed by various types of elastic wave or vibration sources in ambient environment. The real-time state monitoring of such a disturbance is very important in the fields of green buildings and intelligent transportation systems. Based on triboelectric nanogenerators (TENGs), we propose a two-dimensional phononic crystal TENG (PC-TENG), which can serve as a self-powered sensor. The PC-TENG system consists of a periodical spherical cavity type of plate-like structure and elastic balls placed in each spherical cavity. Particularly, with bandgap property of phononic crystals, the proposed PC-TENG can also absorb or suppress vibration impact with certain frequencies acting on buildings and equipment. Taking elasticity, diameter, and surface roughness of elastic ball into account, we established a theoretical model of the cavity-ball type of PC-TENG based on Hertzian contact model. The sensing performance of the proposed PC-TENG with 5 by 5 cavities are experimentally measured, which shows the PC-TENG can efficiently detect the amplitude and frequency of an elastic wave disturbance. The theoretical output charges and currents evaluated from the developed theoretical model agree well with the experimental data.