Total Evaporation Time Research Articles

Evaporation of a heated saline marble: Interplay of interfacial and thermal effects

A multistage evaporation of continuously heated liquid marbles, coated with polytetrafluoroethylene colloidal particles was investigated experimentally and theoretically. Liquid marbles initially contained an almost saturated aqueous NaCl solution. Numerical heat transfer calculations and analytical evaluations of initial evaporation showed that the equilibrium marble temperature and saturated salt concentration are reached relatively rapidly compared to the “long” marble evaporation time. This means that a typical long period of marble evaporation is determined by the low permeability of the salt crust formed beneath the marble colloidal shell. A theoretical estimation of the total evaporation time of marble water based on Darcy's law for the porous crust and the marble shell is suggested. A comparison with experimental data allowed obtaining an approximate value of the very low permeability of this bilayer barrier to marble evaporation. The proposed phenomenological model of the saline marble evaporation provides insight into why marble evaporation is so slow.

Impact of Ceramic Micropillar Array and Fiber Layer Composite Structure on Kinematic and Heat Transfer Characteristics of Single Droplet Impacting a Wall.

The well-known limitations of spray cooling on high-temperature solids at the Leidenfrost temperature point have been significantly improved by a composite structure of steel micropillar arrays and insulating thin films. However, the physical mechanism of a single droplet impact on the walls of high-temperature composite structures in spray cooling remains elusive. We have experimentally studied and quantified the kinematic and thermal transfer characteristics of a single droplet impacting high-temperature micropillar arrays with fiber membrane composite structures. In particular, micropillar arrays of ceramic materials of different shapes (rectangular and cylindrical) used in this study were made using the more flexible PμSL technique, for which precision reaches the micron level. The results show that the presence and different layouts (embedded or placed on top) of the fiber layer significantly affect the spreading coefficient and thermal transfer efficiency of the droplets after impact. In terms of kinematic characteristics, unrelated to the structure of micropillar arrays, compared to structures without film, the maximum spreading coefficient of droplets significantly increased by more than 40% (43% for rectangular, 46% for cylindrical) when the fiber film was placed on top, and increased by more than 20% (20% for rectangular, 33% for cylindrical) when the fiber film was embedded. In terms of thermal transfer characteristics, at a temperature of 200 °C, the presence of the fiber layer changed the wettability of the surface of the micropillar structure, leading to a certain extension of the total evaporation time of the droplets compared to the surface of the micropillar structure without film.

Evaporation of Leidenfrost droplets on microtextured substrates

A thin thermally insulating vapor layer beneath a levitating Leidenfrost droplet adversely affects the heat transfer from the underlying hot substrate during cooling applications. In this work, we present a theoretical model to determine the total heat transfer to a Leidenfrost droplet on microtextured substrates, taking into account the curved shape of the liquid-vapor interface. The profile of the vapor gap and vapor flow field beneath a Leidenfrost droplet on a microtextured surface is shown to be dependent on the substrate morphology. The shape of the liquid-vapor interface beneath the Leidenfrost droplet, in turn, influences the rate of evaporation on a microtextured substrate. We determine the variation of the minimum and maximum vapor gap over micro-pillared surfaces with different substrate permeability for various droplet volumes and wall superheat. The heat transferred to the droplet is via conduction across the vapor gap beneath the droplet and convection from the ambient air around the droplet. We determine the total evaporation time of a Leidenfrost droplet over a micro-textured substrate using the curved interface model and the conventional flat vapor gap interface model and compare with that obtained from experiments. The overprediction of the average rate of evaporation of a Leidenfrost droplet by the flat interface model ranges from ∼59 % for tall and sparse pillars (marked by high substrate permeability) to ∼ 29 % for short pillars (with low substrate permeability). We show that the average rate of evaporation of the LF droplet obtained using the curved interface model agrees reasonably (within 9%–23 %) with that observed in the experiments.

Experimental study on microwave-induced puffing, micro-explosion, and combustion characteristics of ammonium dinitramide-based liquid propellant droplets

Microwave ignition technology has the advantages of high ignition energy, stable ignition, and spatial multi-point ignition. These advantages make this technology promising for future application in green single-component propellants. In this paper, the ignition characteristics of ammonium dinitramide (ADN)-based liquid propellant droplets under the influence of microwaves at room temperature are investigated using experimental methods. The effects of microwave power on puffing, micro-explosion, and combustion behavior of ADN-based liquid propellant droplets were studied. The droplet and flame diameters were statistically related to time, and the microwave-assisted droplet ignition mechanism was analyzed. A new rectangular waveguide resonant cavity was designed in which the droplet is placed at the maximum electric field strength of the device. The droplet morphology and flame profile inside the resonant cavity were photographed with a high-speed camera. The experimental results showed that the microwave positively influenced the puffing, micro-explosion, and combustion behavior of droplets. When the microwave power was increased from 200 to 280 W, the total droplet evaporation time and ignition delay time were reduced by 56.5% and 35.2%, respectively. The positive effects of microwaves on combustion have been summarized as the thermal effect of microwaves on polar molecules and the promotion of fuel oxidation reactions by microwave-induced plasma. The plasma was found to control the development of the initial flame propagation front and to influence the temperature during the combustion reaction process. In this paper, we propose the mode of droplet combustion under microwave induction as a plasma discharge and several stages of the droplet combustion process. This research provides novel insight into the study of the microwave ignition mechanism of liquid fuels.

Numerical simulations of droplet evaporation and breakup effects on heterogeneous detonations

Evaporation and breakup of droplets are critical phenomena in the liquid-fueled, multiphase detonation process. Understanding the relevant conditions and times for each process is crucial for predicting real world behavior. In this paper, the effects of evaporation and breakup on the multiphase detonation process will be explored through Euler-Lagrange (EL) simulations. Various droplet sizes of n-dodecane (C12H26) are reacted with oxygen (O2) utilizing a single-step global reaction mechanism. Droplet processes are modeled using temperature dependent thermophysical properties through the liquid-gas phase change and into the supercritical regime. Two aerodynamic breakup models are considered (based on theorized hydrodynamic instability mechanisms) from both empirical and theoretical approaches. Detonation wave velocity deficits are observed to be sensitive to breakup and evaporation time. It is shown that droplets redistribute fuel vapor mass over their lifetime, perturbing the equivalence ratio and creating vapor rich regions that cannot fully react. It was shown that as the total evaporation time decreases (shorter breakup time), the detonation structure becomes more like the idealized gaseous detonation case.

Surface plasmon resonance imaging for analyzing the local variation of evaporation flux of multiple binary mixture droplets

This study investigates the local variation of concentration and selective evaporation flux affected by the droplet-to-droplet distance during the evaporation of multiple-binary mixture droplets (M-BMDs). Surface plasmon resonance imaging (SPRi) is used to measure the local liquid concentration of the binary mixture droplets and to analyze the spatial distributions of liquid concentration with the estimated local changes of surface tension during evaporation. In addition, we conduct three-dimensional numerical simulations to predict the ethanol vapor distributions and the local ethanol evaporation flux for single- and multiple-binary mixture droplets. It was found that the total evaporation time of M-BMDs is delayed due to vapor accumulation in the region adjacent to the neighboring droplets for M-BMDs, which significantly reduces the local evaporation flux. Also, the local liquid concentration of M-BMDs was found to vary, showing a lower ethanol concentration far away from the adjacent region due to vapor shielding and selective evaporation. Moreover, the scaled lifetime, which is the ratio of evaporation time between multiple droplets and a single droplet, shows good agreement with the previously reported experiments and theoretical models.

Experimental investigation on collision characteristics of dual-spray with different physical-chemical fuel properties: A case study of butanol-biodiesel fuel combination

The dual direct injection strategy can flexibly control the reactivity distributions and equivalence ratio, which shows a great potential in realizing clean and efficient combustion. However, the sprays’ collision is inevitable when the fuel sprays are injected into the combustion chamber simultaneously owing to limited in-cylinder space, which is rarely investigated. The investigation aims to explore the atomization and combustion characteristics of collision between biodiesel and butanol sprays at different injection delay times of biodiesel (0, 0.5, 1, 1.5, 2 ms). Experiments are conducted in a constant volume combustion chamber. The collision spray and combustion images are captured by optical diagnosis techniques. Several macroscopic parameters are obtained, including spray behavior, spray area, ignition delay, ignition location, flame behavior, flame lift-off length, and natural luminosity intensity. Results show that the variation of injection delay time can effectively change the spray distribution and realize the concentration stratification. The liquid-phase diffusion region increases with an increased premixed charge of butanol spray, but the total evaporation time has a tiny difference. The sprays’ collision can promote the ignition process, but the ignition location is slightly affected by the injection delay time of biodiesel. A trade-off relationship between the vapor-phase diffusion area and combustion characteristics is found. When the injection delay time exceeds 0.5 ms, a longer injection delay time can lead to a larger vapor-phase area, which causes smaller equivalent ratio, longer flame-off length, and lower luminosity intensity. However, a longer injection delay would lead to an uncomplete combustion of the n-butanol spray. At the experimental cases, the injection delay time of biodiesel should be 1/2–2/3 injection duration to realize complete combustion and small emissions.

Volatility effect on internal flow and contact line behavior during evaporation of binary mixture droplets

Selective evaporation of binary mixture droplets (BMDs), a phenomenon in which the more volatile components preferentially evaporate, affects contact line behavior, the total evaporation time, and internal flows, such as the solutal Marangoni flow. The surface tension gradient on a BMD is related to the local concentration of its constituents. We analyzed the dependence of the internal flow and contact line behavior on the relative volatilities of the components of ethanol–water and ethylene glycol–water BMDs. Particle image velocimetry (PIV) and shadowgraph methods were simultaneously used to measure the internal flow field and contact line behavior for a BMD, respectively. The results showed that the volatility properties of BMDs affect nonmonotonic contact line behavior during evaporation. Furthermore, the selective evaporation of a highly volatile component of BMDs results in vorticities, and internal circulation flow directions depend on the liquid composition. The averaged absolute vorticity was used to distinguish different stages of internal flow transitions of BMDs.

Mixed-state entanglement and information recovery in thermalized states and evaporating black holes

We study the universal behavior of quantum information-theoretic quantities in thermalized isolated quantum many-body systems and evaporating black holes. In particular, we study a genuine mixed-state entanglement measure called the logarithmic negativity, other correlation measures including the Renyi negativities and the mutual information, and a signature of multipartite entanglement called the reflected entropy. We also probe the feasibility of recovering quantum information from subsystems of a thermalized quantum many-body system or from the radiation of an evaporating black hole, using quantities such as relative entropy and Petz map fidelity. A recently developed technique called the equilibrium approximation allows us to probe these quantities at finite temperature. We find striking qualitative differences from the infinite temperature case, which has been the topic of previous studies using Haar-random states. In particular, we find regimes where the logarithmic negativity is extensive but the mutual information is sub-extensive, indicating a large amount of undistillable, bound entanglement in thermalized states. For evaporating black holes at finite temperature, both the logarithmic negativity and the Petz map fidelity reveal an important new time scale tb, which is earlier than the Page time tp by a finite fraction of the total evaporation time. We find that tb, as opposed to tp, is the time scale at which quantum entanglement between different parts of the radiation becomes extensive, and the fidelity of information recovery for a large diary thrown into the black hole starts to grow.

THE EFFECT OF LIQUID PROPERTIES ON HEAT TRANSFER AND EVAPORATION CHARACTERISTICS OF THE LIQUID FILMS FORMED BY UNSTEADY SPRAY-WALL IMPACTS

For intermittent spray-cooling purpose, it is essential to study the unsteady aspects of film evaporation and heat-transfer characteristics. In the present study, total evaporation time and surface temperature variations are investigated for four different liquid films (water, ethanol, n-octane, and n-hexane). The evaporation process is analyzed using a three-dimensional spray-wall impact with Lagrangian wall-film model. The evaporation process occurs in three stages; at the initial moments, most of the heat is used to raise the film temperature, and slight evaporation also exists. The film temperature rises until it reaches the liquid saturation point to evaporate at a constant rate. In the last stage, the evaporation rate decreases with time due to the accumulation of vapor in the bulk flow. The effect of heat flux and initial film thickness on the total evaporation time and the slope of its changes are investigated. The results show that the total evaporation time increases linearly with the initial thickness. Also, the molecular weight and saturation point of liquids are influential parameters after the enthalpy of evaporation. The surface temperature rises to a maximum value before reducing by the film evaporation. The maximum amount of the wall temperature depends on the liquid thermal conductivity and the evaporation rate. Finally, the effect of the initial value of the film temperature is investigated, and a correlation for estimating the total evaporation time is extracted.

Expansion/micro-explosion of ethanol-biodiesel droplet doped with microparticles in oxygenated hot co-flow

In this paper, under normal pressure and air atmosphere, the single droplet suspension method was used to study the expansion and evaporation characteristics of ethanol-biodiesel mixed droplets under different coal slime particle content and different particle size. In the experiment, a nickel wire was used as a suspension, a stepping motor was used for precise advancement, and the entire evaporation process of the droplet was completely recorded through color gradation processing and binary imaging technology. Experimental results show that the addition of micron-sized slime particles will increase the evaporation rate of droplets. The total evaporation rate (K) of the droplets increases as the content of slime particles increases, making the total evaporation time of the fuel droplets containing 3 % slime particles the shortest. The stable evaporation rate (K3) of the droplets first decreased and then increased, and the stable evaporation rate of the droplets containing 1 % of coal slime particles was the highest. Furthermore, at the same particle content, the evaporation rate of droplets containing 60 μm slime particles was the fastest.

Droplet trampolining on heated surfaces in the transitional boiling regime

Droplet dynamics on a heated surface plays an important role in applications ranging from spray cooling to solidification and pharmaceuticals. Here, we show that in the transitional boiling regime, an unconstrained droplet exhibits trampolining where the droplet bounces to higher heights with each consecutive contact with the substrate. A water droplet of volume 1 μL bounces to a height as high as 6-7 times of its diameter and the height of bounce increases to 18–20 times the diameter as the volume reduces to ∼ 0.1μL. The dynamics of the droplet in the transitional boiling regime results in a non-monotonic variation in the total evaporation time of the droplet with an increase in substrate temperature – an observation that is absent for a constrained droplet. We develop a force-based model to explain the trampolining behavior of the droplet and propose that the gain in momentum of the droplet that results in trampolining is caused by bubble nucleation and escape at the liquid-substrate interface prior to droplet takeoff.

Evaporation of a small water droplet sessile on inclined surfaces

A three-dimensional numerical model is developed to explore the evaporation of a small water droplet sessile on inclined surfaces. Important transport mechanisms, including evaporative cooling, heat transfer, vapor diffusion and natural convections in both liquid and gas domains are taken into account. The accuracy of the present model is first validated by comparing the total evaporation times and volume evolution curves obtained by the present model with those measured from experiments in the literature. The transport details and evaporation characteristics are then investigated. Under the influence of the combining effect of natural convection and evaporative cooling, the overall evaporation rate increases first as the inclination angle gets enlarged till ∼75°, and then decreases with further increase of the inclination angle. The flow field in the gas domain is converted from symmetry to asymmetry with the increase of the inclination angle, and the flow intensity near the droplet is also enhanced, which accelerates the evaporation. At the same time, the local evaporation flux distribution at gas-liquid interface changes from symmetry to asymmetry and the location of the lowest evaporation flux moves from the droplet apex to its waist (on the higher side of the droplet). The total evaporation times of droplets evaporating on vertical surfaces are shorter than those on horizontal surfaces by up to ∼9.38% when the substrate temperature is 40 °C higher than the ambient. The flow behavior inside the droplet is also discussed. With the increase of the inclination angle (0°∼180°), the flow pattern inside the droplet changes from double-vortex flow to single-vortex flow and to double-vortex flow again. The flow velocity magnitude is remarkably increased with the inclination angle increases from 0° to 90°

Investigation on the formic acid evaporation and ignition of formic acid/octanol blend at elevated temperature and pressure

With the growing advancements in new energy sources, formic acid has become a subject of interest as a hydrogen carrier. Apart from being a hydrogen carrier source, to explore the possibility of formic acid being used as a potential fuel in engines, the combustion of formic acid is yet to be explored fully. Few studies have been conducted to determine its laminar burning velocity. The study of droplet combustion and evaporation is also critical if formic acid is to be deployed as a potential fuel. Therefore, the evaporation of formic acid with a droplet diameter of ∼1.00 mm is investigated in a constant volume combustion chamber for pressures ranging from 5 bar to 20 bar at a wide temperature range (150–300 °C). A model was developed to get a fundamental understanding of the experimental results. The D2 plot from experimental data exhibited the presence of two zones for evaporation. Zone 1 showed a slower evaporation rate compared to zone 2. Due to a thin layer of formic acid remaining on the thermocouple, the surface area of the droplet increased in zone 2, resulting in faster evaporation of the droplet. The steeper decline in droplet evaporation occurred at the point of complete loss of sphericity of the droplet. Even so, the trend for total evaporation time from the model and experiments was consistent. Formic acid is a low reactive fuel, and it did not ignite at the ambient temperature and pressure of 300 °C and 20 bar, respectively. So, to determine the auto-ignition behavior of formic acid, a separate experimental setup that could exceed the ambient temperature higher than the auto-ignition temperature of formic acid was used. When pure formic acid did not ignite, it was mixed with octanol at different concentrations and further investigated. The mixture droplet’s ignition probability slightly decreased to 65 vol% of formic acid addition in the octanol. Further addition of formic acid in octanol significantly decreased the ignition probability of the mixture droplet. Lastly, a polynomial equation is proposed to extrapolate the auto-ignition time of pure formic acid droplets with a droplet diameter of ∼0.7 mm.

Evaporation of colloidal droplets from aluminum–magnesium alloy surfaces after laser-texturing and mechanical processing

Evaporation-induced self-assembly on solid surfaces is widely used for the production of photonic devices, circuit boards of electronic devices, and cooling technologies. There are numerous factors affecting self-assembly. However, the state of a solid surface is one of the most important. In this work, we analyzed the effect of mechanical processing methods (widely used in mechanical engineering) and promising pulsed laser texturing of aluminum-magnesium alloy on the characteristics of self-assembly of polystyrene (PS) particles during the evaporation of colloidal solution droplets. The patterns were visualized under a scanning electron microscope. The profile of an evaporating droplet was obtained using the optical shadow technique. It was found that during the evaporation of water droplets loaded with PS particles on aluminum-magnesium alloy samples, the ring-like patterns were formed. Such a pattern type was explained by the evaporation of a droplet in the constant contact diameter mode during almost the entire evaporation time (more than 90% of the total evaporation time). The dried patterns formed on aluminum-magnesium alloy surfaces after satin-finishing and laser texturing were found to be stretched parallel to the vector of laser beam or polishing tool movement due to capillary force. In addition, we determined the conditions when the particles formed spot-like patterns on laser-textured surfaces. These results provide new knowledge in understanding the effect of different processing methods of a material on the formation of dried patterns and are important for many applications.

Local mass flux and pinning behavior of an evaporating droplet on heated aluminum surfaces

The present study aims to investigate the characteristics of pinning behaviors and local mass flux variations during droplet evaporation at different surface temperatures ranging from 22.5 °C to 80 °C. An evaporating droplet is visualized by a CMOS camera, and the images are analyzed from droplet deposition to completion of evaporation. We measure the contact angle, the contact diameter, the droplet volume, the total evaporation time, and the pinning time during evaporation. The pinning time and Marangoni number increase with surface temperatures in the range from 20 °C to 50 °C; however, they decrease at surface temperatures higher than 50 °C. Moreover, the present study analyzes the local mass flux variation according to the surface temperature, showing the increase in the local mass flux over time. We also consider the change in vapor concentrations for the heated surfaces to estimate the local mass flux. Indeed, the local mass flux at the contact line becomes much higher; it experiences over a 10-fold increase from 0.1tf to 0.9tf.

Dynamics of droplet impact and evaporation on the regular micro-grooved and irregular microstructured surfaces

The dynamics of droplet impact and evaporation on the regular micro-grooved and irregular microstructured surfaces are experimentally investigated in this study. The regular micro-grooved and irregular micro structured surfaces are fabricated by a method combining ultraviolet lithography and Ni micro-electroforming process, and electrochemical etching, respectively. It is found that the surface temperature has little effect on the curves of spreading factor in the first spreading phase, as the first spreading phase is governed by the impact of the kinetic energy. At low surface temperature, the total evaporation time for three surfaces is almost same. When the surface temperature exceeds 100 °C, the total evaporation time for the three surfaces shows the differences, and in this regime the droplet mass can mainly be accelerated by the formation of bubbles. At the surface temperature of 104 °C, the micro-cavities of irregular microstructured surface provide more active nucleation sites than that of flat and regular micro-grooved surfaces, which contributes to shorten the total evaporation time. At the surface temperature of 165 °C, the large amount of secondary droplets eject outward on the flat surface, which has not been seen on the regular micro-grooved and irregular microstructured surfaces.

Effect of Particle Concentration on Surfactant-Induced Alteration of the Contact Line Deposition in Evaporating Sessile Droplets.

Controlling and suppressing the so-called "coffee-ring effect" (CRE) is an issue of cardinal importance and intense interest in many industries and scientific fields. Here, the combined effect of the particle and surfactant concentration on the CRE is investigated by gradually adding Triton X-100 surfactant to colloidal suspensions of SiO2 nanoparticles in ethanol for various particle concentrations. First, the effect of particle concentration on the contact line dynamics during the evaporation of a sessile droplet is investigated. It is shown that increasing the particle concentration leads to an increase in pinning time and ring width, whereas the droplet's initial and dynamic contact angle remains unchanged. Afterward, the effect of different concentrations of surfactant is studied for different particle concentrations. It is concluded that the surfactant concentration at which the CRE is suppressed is dependent on the initial particle concentration of the colloid, and it increases as the particle concentration increases. Furthermore, as adding surfactant with a concentration lower than this critical concentration results in an unsuppressed CRE, it is shown that surpassing this concentration will result in a depletion of particles in the contact line. Moreover, it is demonstrated that this critical surfactant concentration has no significant effect on the droplet's geometry and the total evaporation time.

Evaporation of Initially Heated Sessile Droplets and the Resultant Dried Colloidal Deposits on Substrates Held at Ambient Temperature.

The present study experimentally and numerically investigates the evaporation and resultant patterns of dried deposits of aqueous colloidal sessile droplets when the droplets are initially elevated to a high temperature before being placed on a substrate held at ambient temperature. The system is then released for natural evaporation without applying any external perturbation. Infrared thermography and optical profilometry are used as essential tools for interfacial temperature measurements and quantification of coffee-ring dimensions, respectively. Initially, a significant temperature gradient exists along the liquid-gas interface as soon as the droplet is deposited on the substrate, which triggers a Marangoni stress-induced recirculation flow directed from the top of the droplet toward the contact line along the liquid-gas interface. Thus, the flow is in the reverse direction to that seen in the conventional substrate heating case. Interestingly, this temperature gradient decays rapidly within the first 10% of the total evaporation time and the droplet-substrate system reaches thermal equilibrium with ambient thereafter. Despite the fast decay of the temperature gradient, the coffee-ring dimensions significantly diminish, leading to an inner deposit. A reduction of 50-70% in the coffee-ring dimensions is recorded by elevating the initial droplet temperature from 25 to 75 °C for suspended particle concentration varying between 0.05 and 1.0% v/v. This suppression of the coffee-ring effect is attributed to the fact that the initial Marangoni stress-induced recirculation flow continues until the last stage of evaporation, even after the interfacial temperature gradient vanishes. This is essentially a consequence of liquid inertia. Finally, a finite-element-based two-dimensional modeling in axisymmetric geometry is found to capture the measurements with reasonable fidelity and the hypothesis considered in the present study corroborates well with a first approximation qualitative scaling analysis. Overall, together with a new experimental condition, the present investigation discloses a distinct nature of Marangoni stress-induced flow in a drying droplet and its role in influencing the associated colloidal deposits, which was not explored previously. The insights gained from this study are useful to advance technical applications such as spray cooling, inkjet printing, bioassays, etc.

Parallel Droplet Deposition via a Superhydrophobic Plate with Integrated Heater and Temperature Sensors.

A simple setup, which is suitable for parallel deposition of homogenous liquids with a precise volume (dosage), is presented. First, liquid is dispensed as an array of droplets onto a superhydrophobic dosage plate, featuring a 3 × 3 array of holes. The droplets rest on these holes and evaporate with time until they are small enough to pass through them to be used on the final target, where a precise amount of liquid is required. The system can be fabricated easily and operates in a highly parallel manner. The design of the superhydrophobic dosage plate can be adjusted, in terms of the hole positions and sizes, in order to meet different specifications. This makes the proposed system extremely flexible. The initial dispensed droplet mass is not significant, as the dosing takes place during the evaporation process, where the dosage is determined by the hole diameter. In order to speed up the evaporation process, microheaters are screen printed on the back side of the dosage plate. To characterize the temperature distribution caused by the microheaters, temperature sensors are screen printed on the top side of the dosage plate as well. Experimental data regarding the temperature sensors, the microheaters, and the performance of the setup are presented, and the improvement due to the heating of the dosage plate is assessed. A significant reduction of the total evaporation time due to the microheaters was observed. The improvement caused by the temperature increase was found to follow a power law. At a substrate temperature of 80 °C, the total evaporation time was reduced by about 79%.