Modelling of spheroidal drop evaporation with non-uniform temperature conditions

[EN] The heating and evaporation of single component spherical and spheroidal drops in gaseous quiescent environment are predicted, accounting for the effect of a non-uniform distribution of the temperature at the drop surface. The analytical solution of the species conservation equations in the proper coordinate system (spherical/spheroidal) is implemented to numerically solve the energy equation in a rectangular domain. The effect of temperature non-uniformity on the local Nusselt number and global heat and evaporation rates is calculated for different species, drop deformation and gaseous temperature.Cossali, G.; Ravasio, S.; Tonini, S. (2017). Modelling of spheroidal drop evaporation with non-uniform temperature conditions. En Ilass Europe. 28th european conference on Liquid Atomization and Spray Systems. Editorial Universitat Politècnica de València. 75-82. https://doi.org/10.4995/ILASS2017.2017.4721OCS758

Comparison between molar- and mass-based approaches to drop evaporation modelling

Three evaporation models for single-component liquid drop floating in a gaseous environment are compared: two of them rely on the widely used assumption of constant (molar or mass) density and yield an explicit formula for the evaporation rate, while the third model relieves the constant density hypothesis yielding an implicit form of the evaporation rate. The comparison is made for a relative wide range of temperature and pressure operating conditions and for three liquids: water, n-octane and n-dodecane.Papers presented to the 12th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Costa de Sol, Spain on 11-13 July 2016

The Benefits of Writing in Educational Practice with Adolescents. An Experience at a Therapeutic Day Care Center

The present paper illustrates an autobiographical writing experience carried out in a therapeutic day care center involving nine preadolescents and adolescents with moderate to severe mental distress. According to the literature, autobiographical writing is an useful tool to improve educational work with teenagers, because it can accommodate the need to express themselves that characterizes the adolescence and can prevent or reduce feelings of distress. Autobiographical practice is particularly suitable to work with teenagers because it is focused on the question “Who am I?”, which is typical of adolescence. This question was the central theme of the autobiographical writing workshop. During the workshop, was proposed an introspective journey in search of one’s identity between past (who was I?), present (who am I?) and a possible future (who do I want to become?). This article will describe the themes and various stimuli that were proposed during the meetings and will present and discuss the results achieved

Drop Impact on Liquid Surfaces: Formation of Lens and Spherical Drops at the Air-Liquid Interface

Droplets at the air-liquid interface of immiscible liquids usually form partially-submerged lens shapes (e.g. water on oil). In addition to this structure, we showed that droplets released from critical heights above the target liquid can sustain the impact and at the end maintain a spherical ball-shape configuration above the surface, despite undergoing large deformation. Spherical drops are unstable and will transform into the lens mode due to slight disturbances. Precision dispensing needles with various tip diameter sizes were used to release pendant drops of deionized water onto the surface of fluorocarbon liquid (FC-43, 3M). A cubic relationship was found between the nozzle tip diameter and the released droplet diameter. Drop impact was recorded by a high speed camera at a rate of 2000 frames per second. In order for the water drops to sustain the impact and retain a spherical configuration at the surface of the target liquid pool, it is required that they be of a critical size and be released from a certain height; otherwise the commonly observed lens shape droplets will form at the surface

Single droplet impacts onto deposited drops. Numerical analysis and comparison

The impact of a spherical water droplet onto a stationary sessile droplet lying on a solid wall is studied numerically using the volume-of-fluid methodology. The governing Navier-Stokes equations are solved both for the gas and liquid phase coupled with an additional equation for the transport of the liquid interface. An unstructured numerical grid is used along with an adaptive local grid refinement technique, which enhances the accuracy of the numerical results along the liquid-gas interface and decreases the computational cost. The stationary sessile droplet has been created from the prior impact of one or two water droplets falling onto the solid wall, while two solid walls have been studied−an aluminum substrate and a glass substrate. The material of the wall plays an important role because it has an impact on the droplet's wetting behavior. The numerical model is validated against corresponding experimental data presented in the first part of the present work (Nikolopoulos et al., 2010), showing good agreement. Furthermore, the numerical investigation sheds light on the governing physics of the phenomenon

Stereotactic radiotherapy with simultaneous integrated protection planning technique for synovial sarcoma with stomach abutment: A case report of a complete response

Here, we report the clinical case of a 44-year-old lady, affected by synovial sarcoma (SS) of the mediastinum which was treated in 2014, and relapsed in the upper abdomen in 2020. SS is a relatively radioresistant disease, radiotherapy (RT) is routinely reserved for the neoadjuvant/adjuvant or palliative context. In our scenario, stereotactic RT consisting in 45Gy in 6 fractions was proposed to manage the upper abdominal relapse. Exploiting simultaneous integrated protection, a deliberated reduction in the dose prescription in area of planning target volume overlapped with stomach was achieved, obtaining reasonable dosimetric goals. Acute toxicity in the patient was acceptable, and she did not experience late toxicity and was still free from disease, as noted in last follow-up, 15 months after treatment

Early results of PRO-EPI: PROspective multicenter observational study on elective pelvic nodes irradiation in patients with intermediate/high/very high-risk non-metastatic prostate cancer submitted to radical, adjuvant, or salvage radiotherapy with or without concomitant androgen deprivation therapy

Simple Summary: Although radiotherapy plays a fundamental role in the management of intermediate/high/very high-risk non-metastatic prostatic cancer (IHR-nmPca), there is still no consensus on the optimal treatment strategy in this setting. Remarkably, the role of elective nodal irradiation (ENI) is still highly controversial. The PROspective multicenter observational study on Elective Pelvic nodes Irradiation (PRO-EPI) was designed to provide "real life" data regarding the patterns of care for IHR-nmPca.Forty-three Italian Radiation Oncology centers participated in the PROspective multicenter observational study on Elective Pelvic nodes Irradiation (PRO-EPI) project, with 1029 patients enrolled. In this preliminary analysis, we longitudinally evaluated the impact of Elective Nodal Irradiation (ENI) and radiotherapy features on toxicity and quality of life (QoL). Six months follow-up data were available for 913 patients and 12 months data for 762 patients. Elective Nodal Irradiation was given to 506 patients (48.9%). Volumetric Intensity-Modulated Radiation Therapy (IMRT) was adopted in more than 77% of patients and Image-Guided Radiation Therapy (IGRT) in 84.4%. Androgen deprivation therapy (ADT) was administered to the majority of patients (68.3%), and it was associated to ENI in 408 cases (81.1%). Toxicity was mostly mild and reversible and IGRT resulted in a significant reduction of rectal toxicity, although a non-significant trend toward increased urinary toxicity was observed. No statistically significant differences in QoL and toxicity were seen in patients treated with or without ENI. The adoption of IGRT is widespread and increasing and could reduce treatment toxicity. ENI is not yet the standard treatment, but it is performed in a growing fraction of cases and not resulting into an increase in toxicity or in a deterioration of QoL. Further analyses are needed to clarify the long-term toxicity profile and the impact of ENI on survival