This paper is focus on design and fabrication of Automatic solar operated lake cleaning floating machine. This project basically concentrated to clean the lake. Based on the current problem in the lake, we designed and fabricated a floating machine. Our project is remotely operated lake cleaning machine, aim to be preventing human accident and minimize error during the operation. Also, in order to minimize the emission, we used electric energy as an energy resource for our project.

The current analysis aims to review the effectiveness of the flow regulations at Mach 1.87, a considerably large Mach number. The duct radius is 11 mm, and the diameter ratio concerning the exit of the nozzle is 2.2. Tests were done at different expansion levels for eight different duct sizes. Here we are pondering in a situation where there is a considerable variation of pressure is noticed. The flow control was located at a PCD of 13 mm from the axis. The control jets of 0.001 m diameter producing a Mach unity jet, used as energetic flow control. For shorter tube sections at smaller NPRs, the pressure undertakes a minimal value. Soon After, with an increase of the tube size and expansion levels, a continuing fall in pressure owing to the decline in the level of adverse pressure and shock waves intensity. Flow fluctuations are witnessed for various duct sizes. The duct size represents a vital part while ascertaining the flow advancement in the duct. Relatively high pressure is seen for duct length L = 132 mm and L = 220 mm for nozzle pressure ratios three and five. The pressure becomes modest due to the effect of duct size. For NPR = 7, an increase in pressure is restricted by the separated zone, and atmospheric restrictions are almost accomplished. For the 10D duct, the realization of the ambient condition is additionally enhanced near the upstream. Copyright (C) 2021 Elsevier Ltd. All rights reserved.

This study investigates the streaming development in the tube and pressure recovery once the flow regulator is activated in the recirculation zone at a different level of expansions. The Mach numbers considered are 1.87, 2.2, 2.58. The duct diameter is 16 mm. Tiny jets of 1 mm diameter are placed at the midplane of the base to regulate the flow. The control jet's Mach number is unity as they are circular orifice despite the NPR of the control jet being very high. The investigations reveal that the stream remained connected with the duct even for L = 1D for the entire Mach numbers. The pressure's initial values are very high for an over-expanded nozzle than the under-expanded and ideally expanded nozzles. From the wall duct field, it is seen that the flow becomes oscillatory for lengths L = 10D to 6D owing to the collaborations of the waves, the duct wall, and the influence of the ambient pressure. The recovery of the tube pressure also gets shifted towards the downstream for the more considerable duct lengths. The flow quality with and with no flow control mechanism is identical for duct lengths 10D and 8D. Lower duct lengths show mixed trends regarding flow development, and the flow's quality is concerned. The flow control mechanism is effective once the nozzle flows with favorable pressure or at the design NPRs. When the nozzle has more pressure than ambient values, the control becomes useful, quickly raising the pressure's values. Copyright (c) 2021 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the 3rd International Conference on Contemporary Advances in Mechanical Engineering