Opening Mode Research Articles

Using in-situ strain measurements to evaluate the accuracy of stress estimation procedures from fracture injection/shut-in tests

Fracture injection/shut-in tests are commonly used to measure the state of stress in the subsurface. Injection creates a hydraulic fracture (or in some cases, opens a preexisting fracture), and then the pressure after shut-in is monitored to identify fracture closure. Different interpretation procedures have been proposed for estimating closure, and the procedures sometimes yield significantly different results. In this study, direct, in-situ strain measurements are used to observe fracture reopening and closure. The tests were performed as part of the EGS Collab project, a mesoscale project performed at 1.25 and 1.5 km depth at the Sanford Underground Research Facility. The tests were instrumented with the SIMFIP tool, a double-packer probe with a high-resolution three-dimensional borehole displacement sensor. The measurements provide a direct observation of the fracture closure signature, enabling a high-fidelity estimate of the fracture closure stress (ie, the normal stress on the fracture). In two of the four tests, injection created an opening mode fracture, and so the closure stress can be interpreted as the minimum principal stress. In the other two tests, injection probably opened preexisting natural fractures, and so the closure stress can be interpreted as the normal stress on the fractures. The strain measurements are compared against different proposed methods for estimating closure stress from pressure transients. The shut-in transients are analyzed with two techniques that are widely used in the field of petroleum engineering – the ‘tangent’ method and the ‘compliance’ method. In three of the four tests, the tangent method significantly underestimates the closure stress. The compliance method is reasonably accurate in all four tests. Closure stress is also interpreted using two other commonly-used methods – ‘first deviation from linearity’ and the method of (Hayashi and Haimson, 1991). In comparison with the SIMFIP data, these methods tend to overestimate the closure stress, evidently because they identify closure from early-time transient effects, such as near-wellbore tortuosity. In two of the tests, microseismic imaging provides an independent estimate of the size of the fracture created by injection. When combined with a simple mass balance calculation, the SIMFIP stress measurements yield predictions of fracture size that are reasonably consistent with the estimates from microseismic. The calculations imply an apparent fracture toughness 2-3x higher than typical laboratory-derived values.

Enhanced removal of antibiotic and antibiotic resistance genes by coupling biofilm electrode reactor and manganese ore substrate up-flow microbial fuel cell constructed wetland system

Manganese ore substrate up-flow microbial fuel cell constructed wetland (UCW-MFC(Mn)) as an innovative wastewater treatment technology for purifying antibiotics and electricity generation with few antibiotic resistance genes (ARGs) generation has attracted attention. However, antibiotic purifying effects should be further enhanced. In this study, a biofilm electrode reactor (BER) that needs direct current driving was powered by a Mn ore anode (UCW-MFC(Mn)) to form a coupled system without requiring direct-current source. Removal efficiencies of sulfadiazine (SDZ), ciprofloxacin (CIP) and the corresponding ARGs in the coupled system were compared with composite (BER was powered by direct-current source) and anaerobic systems (both of BER and UCW-MFC were in open circuit mode). The result showed that higher antibiotic removal efficiency (94% for SDZ and 99.1% for CIP) in the coupled system was achieved than the anaerobic system (88.5% for SDZ and 98.2% for CIP). Moreover, electrical stimulation reduced antibiotic selective pressure and horizontal gene transfer potential in BER, and UCW-MFC further reduced ARG abundances by strengthening the electro-adsorption of ARG hosts determined by Network analysis. Bacterial community diversity continuously decreased in BER while it increased in UCW-MFC, indicating that BER mitigated the toxicity of antibiotic. Degree of modularity, some functional bacteria (antibiotic degrading bacteria, fermentative bacteria and EAB), and P450 enzyme related to antibiotic and xenobiotics biodegradation genes were enriched in electric field existing UCW-MFC, accounting for the higher degradation efficiency. In conclusion, this study provided an effective strategy for removing antibiotics and ARGs in wastewater by operating a BER-UCW-MFC coupled system.

A complete characterization of THE fracture forming limits in bulk forming by means of an upset geometry sequence

This paper presents an upset geometry sequence to determine the fracture forming limits in a wide variety of strain loading paths ranging from uniaxial compression to equibiaxial tension. The strains at fracture in principal strain space are obtained by combination of digital image correlation and experimental evolutions of the compression force versus time, and their representation in the effective strain versus stress triaxiality space is accomplished by means of a new analytical framework that uses the instantaneous slope of the strain loading paths. Modeling of the experimental strains at fracture by means of an uncoupled ductile fracture criterion built upon combination of the Cockcroft-Latham and McClintock criteria and fractography analysis using a scanning electron microscope allow understanding and characterizing the crack opening modes by shear and tension as well as the uncertainty region inside which mixed crack opening modes are observed. Results confirm that the overall philosophy and objectives underlying the new upset geometry sequence for determining the fracture forming limits in bulk forming resemble those of the Nakajima test that is commonly used in sheet forming.

Study of the effect of experimental conditions on atomic layer deposition of aluminum nitride films

AlN is an extremely chemically stable material that can withstand high temperature impacts and can be used as a coating against high temperature oxidation. In this paper, AlN films were grown on Si (111) substrates using pulsed chemical vapor deposition with a metal-organic source and ammonia as precursors followed by high-temperature in situ annealing and material physical characterization. The effects of temperature and plasma source on the AlN films were investigated, and it was concluded that the higher the temperature, the higher the growth rate of the AlN films and the lower the oxidation level. The plasma source pulsed mode showed higher growth rate and stronger aluminum signal, but its oxidation level was also higher. The plasma source normally open mode has a more desirable nitrogen signal.

Feasibility of using phase-shifting transformers to increase the throughput of interconnected power transmission systems

This paper discusses measures aimed at improving the efficiency of power systems by increasing the capacity of power transmission lines. To that end, a FACTS technology based on a phase-shifting transformer was used. The feasibility of using phase-shifting transformers to increase the throughput capacity of interconnected power transmission systems was investigated by determining the maximum allowable cross-section flows of the United Energy System of the Urals – the United Energy System of Siberia. The studied cross-section included 500 kV transmission lines and the extended 220 kV Nizhnevartovskaya GRES – Tomskaya transit. Calculations were performed for normal and various post-emergency schemes using the RastrWin3 software package. The regulation of phas e-shifting transformer branches and the direction of power flow in the section were taken into account. For the considered cross -section, the use of a phase-shifting transformer was shown to provide for the 220 kV transit operation in a closed mode. This i mproved the reliability of power supply in the region and allowed the maximum allowable overflow to be increased by 35 – 71%. In addition, similar calculations were carried out for the option of strengthening the 220 kV transit through the construction of a parallel 500 kV line. The effect of increasing the capacity of this option was established to reach 20 –35%. The decisive factor limiting the maximum permissible cross-section flows during 220 kV transit short circuit in the normal and reinforced versions was found to be the current overload of the head sections. Recommendations on the preferable use of an open transit mode are formulated. In conclusion, the efficiency of power systems can be improved by increasing the transmission capacity of power lines through the use of phase-shifting transformers. A segment of the Unified National Power Grid of Russia, where such devices are technologically expedient, was identified.

Experimental Assessment of the Performance of Dual Pneumatic Vitreous Cutters According to Gauge and Cut Rate.

To compare and analyze the performance of dual pneumatic ultra-high-speed vitreous cutters based on their cut rates, vacuum levels, and diameters in terms of flow rate and cutting time. The Constellation Vision System was used to remove egg white for 30 seconds, after which we calculated the flow rate by measuring the change in weight. We then measured the time required to remove 4 mL of egg white. We tested the UltraVit (UV) 7,500 cuts per minute (cpm) probe and the Advanced UltraVit (AUV) 10,000 cpm probe in biased open duty cycle mode, using 23-, 25-, and 27-gauge probes, respectively. In biased open duty cycle, the flow rate tended to decrease as the cut rates increased for all three gauges. At the same cut rates, the flow rate increased as the vacuum level increased (p < 0.05), and as the diameter increased (p < 0.05). Among cutters with the same diameter, the AUV cutter showed higher flow rates than the UV cutter, with increases of 0.267 mL/min (18.5%) at 27 gauge, 0.627 mL/min (20.8%) at 25 gauge, and 1.000 mL/min (20.7%) at 23 gauge (all p < 0.05). The times required to remove 4 mL of egg white took longer with the UV cutter than the AUV cutter for all three gauges (all p < 0.05). The use of a smaller gauge vitreous cutter may reduce the flow rate and increase the time required for vitrectomy, but this can be partially compensated for by increasing the vacuum level as well as using a vitreous cutter with a higher maximum cut rate, improved port size, and improved duty cycle.

Numerical modeling of low-frequency distributed acoustic sensing signals for mixed-mode reactivation

In recent years, the development of distributed acoustic sensing (DAS) technology has enabled direct monitoring of subsurface strain during hydraulic fracturing (HF) operations. Most low-frequency (<1 Hz) DAS (LFDAS) signals exhibit strain or strain-rate patterns that are characteristic of propagating tensile hydraulic fractures. However, mixed-mode fault reactivation, consisting of shear slip (mode II) with tensile opening (mode I), can occur in cases where propagating hydraulic fractures intersect preexisting natural fractures or faults. In this study, we show an anomalous LFDAS signal that was observed during an HF operation, with characteristics that differ from typical signals from tensile hydraulic fractures. Anomalous characteristics include the onset of an asymmetric compression-extension doublet after pumping was terminated. The location of the signals, coupled with the image log and seismic data, suggests that mixed-mode reactivation occurred on a preexisting fault. We use a simplified numerical model based on the displacement discontinuity method (DDM) to simulate the anomalous LFDAS signal. Results find that the first-order characteristics of the anomalous signal can be approximated as an initial tensile fault opening (mode I) followed by a shear slip (mode II) on a fault. Therefore, we demostrate the approach of using DDM to investigate mixed-mode fault reactivation during HF operations.

A new strategy for predicting fracture of U‐notched specimens made of Al‐6061‐T6 and Al‐5083 using extended finite element method

AbstractThis research focuses on the numerical investigation of fracture loads of U‐notched specimens made of Al‐6061‐T6 and Al‐5083 under pure opening mode and mixed mode I/II loading conditions. A new methodology is introduced with the aid of the equivalent material concept (EMC) combined with the extended finite element method (XFEM) and linear cohesive zone model (CZM), and the outcomes are compared with a conventional elastic–plastic damage model. The combination of EMC and XFEM result in the numerical EMC‐XFEM model, which provides a fast and accurate method to assess the notch fracture loads and crack growth path. Considering the experimental results, a trial and error loop is performed to calibrate the ductile damage model, which is much more cumbersome than the proposed EMC‐XFEM model. Moreover, the computational cost of elastic–plastic model is much more than the EMC‐XFEM model, although both approaches provide appropriate predictions for fracture of ductile aluminum notches.

Finite-element simulation of in-plane tear propagation in the dissected aorta: Implications for the propagation mechanism.

Computer modeling and numerical simulation are essential for understanding the progression of aortic dissection. However, tear propagation has not been properly modeled and simulated. The in-plane dissection propagation between concentrically distributed elastic lamellae is modeled using the cohesive zone method with a bilinear traction-separation law. The parameters of cohesive elements are calibrated for the three modes of interfacial damage in the media, enabling quantitative predictions of in-plane tear propagation. An idealized cylindrical tube-shaped bilayer thick-wall model of the aorta is employed to elucidate the influence of geometrical parameters, loading conditions and residual stress on the tear propagation. While the model is capable of replicating that deeper, larger tears are associated with lower critical pressure, new findings include: (i) Larger axial stretch leads to lower critical pressure; (ii) Increased magnitude of residual stress is associated with higher critical pressure; (iii) Pressure difference between true and false lumen alters the critical pressure; (iv) The interfacial damage is mostly opening mode in the axial direction, but shear-dominated in the circumferential direction; (v) Damage due to the opening mode is associated with smaller fracture energy, which makes it easier to propagate than the shear and the mixed modes. (vi) The deformed shape of the tear, which is related to its geometrical features and loading conditions, modulates the critical pressure via two pathways: (a) deformed shapes are associated with specific modes of damage, which influences the critical pressure, and (b) deformed shapes modulate the critical pressure directly via geometrical constraints.

Mixed mode (I&III) fracture behavior of cement emulsified asphalt mortar under freeze and thaw cycles

The present study was designed to evaluate the impact of freeze and thaw cycles on pure tensile (I), pure shear (III), and mixed tensile–shear (I/III) fracture of Cement Emulsified Asphalt Mortar (CEAM) with diverse mix designs. For this purpose, a large number of Edge Notched Disk Bend (ENDB) specimens were fabricated with 16 different random mixture designs with various amounts of cement content (C) and different proportions asphalt-to-cement (A/C) and water-to-cement (W/C) proportions. The specimens of each mix design were divided into five groups: one control group (no freeze and thaw) and four test groups where the specimens underwent 1, 3, 5 and, 10 cycles of freezing and thawing. All of the specimens were then fractured in pure opening mode (I), pure tearing mode (III), and mixed opening–tearing modes (I/III). The results evinced that applying the cycles of freezing and thawing diminished the mortar’s fracture energy in each of the three modes. This drop was more intense after the initial cycles and became less so with an addition in cycles. The freeze and thaw-induced change in the fracture properties was measured in terms of the ratio of the fracture energy of the conditioned specimen in the specified mode to that of the control specimen, denoted by FERi. The FERi of mortars with different mix designs was estimated by developing multiple regression models to explain the relationship between this index’s experimental values and mix design variables (A/C, W/C, C) at the 0.05 significance level. Among the independent variables, A/C had the greatest effect on mode-I fracture energy changes, and C had the greatest effect on mode III and mixed-mode I/III fracture energy changes due to the freeze and thaw damage. Considering the predicted FERi values, freeze and thaw cycles appear to have more damaging effects on the mixed mode I/III fracture properties of CEAM.

“There are two sides to everything”: Re (locating) vulnerability in the surrogacy industry in India

Vulnerability is a pivotal concept for understanding transnational commercial surrogacy and the ethics of reproductive travel. While implicitly recognizing vulnerability as important, existing scholarship falls short of understanding the dynamism of vulnerability. Placing our empirical analysis in conjunction with the rich theoretical literature on this concept, we explore vulnerability in surrogacy arrangements in India as a “mode of openness,” defined by its multilayeredness and context specificity. We focus on two retellings of vulnerability. In the first narrative, we analyse the journey of an intended parent who becomes an agent, while in the second narrative, we focus on the trajectory of a surrogate and egg donor becoming an agent. In both narratives, the layers of vulnerability across different interconnected circuits of reproduction—of intended parent, agent, and surrogate—are explicated. Our analysis illustrates the complex and conflicting meanings of vulnerability and illustrates vulnerability as an instigator of agency and resistance; how it can propel upward social mobility and animate attempts to transform an unjust system, but also how such individual agency and empowerment may serve to uphold exploitative relationships.

Investigation of resistance spot weld failure in tailor hot stamped assemblies

A novel experimental method, dubbed the “Mode I Caiman test”, is introduced to characterize spot weld failure and propagation within spot weld groups. The test configuration comprises a partially welded pair of channel sections subjected to Mode I tensile loading through an opening mode loading applied at the un-welded end of the channels. Experiments were performed considering hot stamped USIBOR® 1500-AS in a fully hardened condition (fully quenched) or in a tailored condition in which the strength of the welded flanged regions was altered using in-die heating (IDH). Both static and dynamic loading conditions are considered. The static loading utilized a conventional tensile frame while the dynamic experiments were performed on an instrumented crash sled at velocities of 7.5 m/s.A high speed thermal imaging camera was utilized to detect the temperature rise associated with plastic work during individual weld failure. This proved to be a rather novel and effective technique to detect weld failure and enabled tracking of weld failure propagation through the weld group for the different parent metal (flange) conditions.The experiments served to demonstrate the complex interaction between weld nugget, heat affected zone (HAZ) and parent metal strengths. For high parent metal strengths (fully quenched, martensitic condition), the welds exhibited interfacial and weld pull-out failure modes with rapid unzipping of the weld group resulting in relatively low energy absorption. In contrast, the lower strength tailored flanges exhibited a more stable (slower) failure propagation through the weld group and considerably higher energy absorption which is largely attributed to greater dissipation through deformation of the flange itself. Numerical simulations of the experiments were performed using spot weld models calibrated from single weld lap shear, cross tension, and coach peel experiments. The models captured the peak loads rather well, but predictions of rate of failure propagation within the weld line exceeded that seen in the experiments, pointing to the need for improved post-failure models for spot weld simulation.In automotive structures in which numerous welds are present, the amount of energy absorbed in weld failure can significantly affect the impact response of the structure. The Mode I Caiman test presents a new opportunity to calibrate the energy release rate of spot weld damage models to improve their accuracy when modelling spot welded connections involving multiple spot welds.

VO-Notches Subjected to Tension-Torsion Loading: Experimental and Theoretical Fracture Study on Polymeric Samples.

In this research, the fracture behavior of brittle specimens weakened by V-shaped notches with end holes (VO-notches) is studied. First, an experimental investigation is conducted to evaluate the effect of VO-notches on fracture behavior. To this end, VO-notched samples of PMMA are made and exposed to pure opening mode loading, pure tearing mode loading, and some combinations of these two loading types. As part of this study, samples with end-hole radii of 1, 2, and 4 mm are prepared to determine the effect of the notch end-hole size on the fracture resistance. Second, two well-known stress-based criteria, namely the maximum tangential stress (MTS) criterion and the mean stress (MS) criterion, are developed for VO-shaped notches subjected to mixed-mode I/III loading, also determining the associated fracture limit curves. A comparison between the theoretical and the experimental critical conditions indicates that the resulting VO-MTS and VO-MS criteria predict the fracture resistance of VO-notched samples with about 92% and 90% accuracy, respectively, confirming their capacity to estimate fracture conditions.

Experimental determination of the fracture forming limits in metal forming

This paper revisits the determination of the fracture forming limits in metal forming with the purpose of providing readers understanding on the experimental procedures and identification of their pitfalls and sources of error. The presentation covers fracture in sheet and bulk metal forming under three different crack opening modes: by tension (mode I of fracture mechanics), by in-plane shear (mode II), and by out-of-plane shear (mode III). It is shown that the determination of the fracture forming limits must account for the specificities of sheet forming, which is fundamentally based on material flow under plane stress conditions, and of bulk forming, which essentially features material flow under three-dimensional conditions. The content of the paper is an attempt to merge previous work of the authors in the determination of the fracture forming limits, which is scattered through various publications, so that a comprehensive view of their accumulated experience in sheet and bulk forming can be provided in a single publication.

The role of makerspaces in innovation processes: an exploratory study

Makerspaces democratize technology access and therefore improve the chances for innovation and entrepreneurship. Nevertheless, we know little about how innovation happens in collaborative innovation spaces like makerspaces. To unleash the full potential of makerspaces, it is essential to understand what resources and environments support innovation for makerspace users. Against this background, this research study aims to explore how different makerspace user groups leverage makerspace resources during their innovation process. To achieve this, we use the resource‐based view in combination with an open innovation perspective and examine the relevance of makerspace resources (knowledge, technology, social, and financial) during the different stages of the innovation journey (ideation, development and prototyping, commercialization and diffusion). In contrast to prior work, we focus on different makerspace user groups within an industry‐specific makerspace and investigate how open innovation strategies (inbound, outbound, and coupled) are used to leverage the makerspace resources to develop innovation projects. Since the object of investigation is broadly unexplored and complex, we use an embedded single case study approach to explore 10 different projects within a makerspace with a specific focus on photonics. Photonics is described as a so‐called enabling technology that carries a considerable potential for cross‐industry innovation. The qualitative content analysis revealed that professional and hobby users differ in their makerspace resource use and their modes of openness across the innovation journey. Furthermore, we find that makerspaces can take the role of a facilitator or incubator depending on who uses the makerspace to innovate.

Numerical investigation on thrust characteristics of an annular expansion–deflection nozzle

The thrust characteristics of a large-expansion-ratio annular expansion–deflection (ED) nozzle are investigated based on detailed flow pattern simulations. The purpose is to build a bridge between the nozzle internal flow pattern and nozzle thrust performance. The present work traces flow parameters along typical streamlines to demonstrate the nozzle flow pattern, partitions the nozzle exit plane based on its flow features to evaluate thrust contributions of each thrust coefficient contributor in different sub-areas, and monitors flow parameter distributions in the nozzle exit plane at 22 nozzle pressure ratios to interpret the developing histories of nozzle thrust coefficients. The present simulations show that the shocks generated in open wake mode are both inevitable and indispensable, while the shocks generated in closed wake mode contribute negatively to thrust performance. Three basic requests for designing a high-performance ED nozzle are clarified, which are to ensure high-quality expansion at the nozzle throat, to smooth out the reflected shock in open wake mode, and to diminish the strong near-wall shock generated in closed wake mode. An interesting and counter-intuitive phenomenon, namely, the existence of the reflected shock in open wake mode not only consumes the ability of the exhaust flow to do work but also improves the overall nozzle thrust performance, is explained. This is because the reflected shock deflects lateral-going exhaust flow to the axial direction. When this reflected shock disappears, a sudden drop in the nozzle thrust coefficient history takes place.

GEODATA OF THE MOSCOW UNIVERSITY HERBARIUM: DATA STRUCTURE AND GEOREFERENCING METHODICS

Digitisation of the Moscow University Herbarium (MW) was started in the spring of 2015. Since October 2016, we have been publishing the images of specimens on the portal of the Moscow Digital Herbarium (https://plant.depo.msu.ru/) in open access mode. Gradually, we started to publish extended metadata on our portal, like full transcriptions of labels and georeferences, i.e. the coordinates of collection sites for each specimen. As of January, 14, 2023, two thirds of the specimens of the Moscow University Herbarium (693168 specimens, or 66%) are georeferenced, while 359593 specimens are still in work. The article describes the geodata of the Moscow University Herbarium both in the geographical aspect (data coverage for different regions) and in the aspect of georeferencing accuracy. General guidelines for georeferencing herbarium collections are given.

Numerical simulation of fiber–matrix debonding: Inverse identification of interface properties

Fiber-matrix interface debonding is studied by means of single-fiber epoxy-glass fiber specimens under transverse tensile loading. Experimental observations show abrupt debonding initiation between 67 and 83 deg. followed by stable debonding propagation. Similar abrupt debonding initiation is predicted using the coupled criterion (CC). The latter predicts crack initiation considering both stress and energy aspects from which a range of interface shear and opening critical energy release rates (ERR) and strengths can be derived. Depending on these parameters, initiation is found to be either driven by energy solely or by both stress and energy conditions. The loading required for initiation depends on the opening (mode I) critical ERR and tensile and shear strengths. The debonding arrest angle also depends on the shear (mode II) critical ERR. Consequently, a three steps methodology to identify the interface properties is described and an optimum set of parameters is determined by focusing on the stable debonding propagation after initiation using Linear Elastic Fracture Mechanics.

Fundamental understanding of open keyhole effect in plasma arc welding

The keyhole arc welding technique has the advantage of improving welding efficiency by utilizing a stable keyhole mode. Accurate understanding of the keyhole effect is necessary to enhance the welding quality. Due to the high temperature and strong arc force involved, the complex gas–liquid–solid interactions in the complete keyhole process need to be explored. In order to fully demonstrate open keyhole mode welding, a three-tier sandwiched model based on multiphysics and multiphase effects was developed. The top layer of the model is filled with plasma arc, which gradually fuses and penetrates through the middle metal layer. Finally, it enters the third layer, resulting in an open keyhole mode. Multiphysics phenomena due to the plasma arc are fully included in the model, and the gas–liquid–solid interactions are calculated by combining the Volume of Fluid technique and the Enthalpy-porous technique. Arc ignition and dynamic open keyhole effect are demonstrated, and an arc discharge is shown from the open keyhole exit. The arc reflection phenomenon is observed as the arc is blocked by the weld pool frontier. The electric current path varies with the welding movement, and most of the current comes from the weld pool frontier. An experiment was conducted to obtain weld pool and keyhole images, which basically agree with the calculated results. Additionally, the calculated open keyhole time and electric potential drops also coincide well with experimental data.

Drying Kinetics and Performance Analysis of Thermal Storage-Based Hybrid Greenhouse Dryer for Uniform Drying of Tomato Flakes

Abstract This communication focuses on the experimental investigation of mixed heat storage-based hybrid greenhouse dryer. The proposed system is a combination of a solar air heater and a greenhouse dryer. Mixed heat storage material is applied on the bed of the dryer, which is a combination of paraffin wax and black-painted gravel. Tomato flakes were selected for drying in both hybrid system and natural sun drying. Tomato flakes were rehydrated up to 1.29% and 10.10% under hybrid and open modes. Daily drying efficiency for drying tomato flakes in the proposed dryer was 50.18%, while it was 30.02% for open mode. Effective moisture diffusivity was 0.8666 × 10−10 m2/s and 11.650 × 10−10 m2/s for open and hybrid modes. The solar drying process improved physicochemical properties of tomato flakes, resulting in a shelf life extension. This finding highlights the great potential for hybrid solar dryer in the food industry and suggests that it could emerge as an efficient postharvest conserving method for seasonal consumable vegetables and fruits, mostly in developing nations.