New infant cranium from the African Miocene sheds light on ape evolution

The evolutionary history of extant hominoids (humans and apes) remains poorly understood. The African fossil record during the crucial time period, the Miocene epoch, largely comprises isolated jaws and teeth, and little is known about ape cranial evolution. Here we report on the, to our knowledge, most complete fossil ape cranium yet described, recovered from the 13 million-year-old Middle Miocene site of Napudet, Kenya. The infant specimen, KNM-NP 59050, is assigned to a new species of Nyanzapithecus on the basis of its unerupted permanent teeth, visualized by synchrotron imaging. Its ear canal has a fully ossified tubular ectotympanic, a derived feature linking the species with crown catarrhines. Although it resembles some hylobatids in aspects of its morphology and dental development, it possesses no definitive hylobatid synapomorphies. The combined evidence suggests that nyanzapithecines were stem hominoids close to the origin of extant apes, and that hylobatid-like facial features evolved multiple times during catarrhine evolution

Numerical Simulation of an Aerothermopressor with Incomplete Evaporation for Intercooling of the Gas Turbine Engine

Numerical Simulation of an Aerothermopressor with Incomplete Evaporation for Intercooling of the Gas Turbine Engine / H. Kobalava , D. Konovalov, R. Radchenko, S. Forduy, V. Maksymov // Integrated Computer Technologies in Mechanical Engineering – 2020 : ICTM 2020. Lecture Notes in Networks and Systems, vol. 188 / M. Nechyporuk, V. Pavlikov, D. Kritskiy. – Kharkiv, Ukraine, 2021. – P. 519–530.Complex cycles with cyclic air intercooling are used to increase the energy efficiency of gas turbines. A modern and widespread way to improve the cooling process is to humidify the working fluid (cyclic air). The efficiency of wet compression primarily depends on the intensity of evaporation and heat exchange of droplets with the air flow, which begins to increase sharply when the effective diameter of droplet spraying decreases to 20 lm. It is proposed to use a contact heat exchanger to obtain a finely dispersed flow of water in the flow path of a gas turbine. The operation of such contact heat exchanger called aerothermopressor was investigated in this paper. CFD simulation of the water droplet evaporation process in the aerothermopressor airflow was carried out. Calculations were carried out for three variants of evaporation of water injected into the air flow: complete evaporation of water droplets in the evaporation chamber, additional evaporation of water droplets in the diffuser and incomplete evaporation, with obtaining smaller droplets at the outlet of the aerothermopressor diffuser. Efficiency of the aerothermopressor application in the gas turbine circuit for contact cooling of cyclic air is analyzed. It has been revealed that the aerothermopressor allows increasing the cyclic air pressure between the compressor stages by 2–10%, which will lead to a decrease in the compression work in the compressor stages and makes it possible to increase the gas turbine engine efficiency by 1–2%