ALGORITHM FOR MANAGEMENT AND PROTECTION OF SUBMERSIBLE PUMP

International Conference on Technics Technologies and Education ◽

10.15547/ictte.2019.04.035 ◽

2019 ◽

pp. 245-250

Author(s):

Tanya Pehlivanova

Keyword(s):

Global Warming ◽

Submersible Pump ◽

Groundwater Levels ◽

Frequent Switching ◽

Full Utilization ◽

Level Sensors

Global warming has led to lower levels of the water basins. Groundwater levels also decrease. Sometimes they fall so much so that submersible pumps in the wells remain almost dry and even in short work cycles get damaged. Their repairs are very expensive and labour intensive. An algorithm for management and protection of submersible pump is proposed in the paper. It uses 5 level sensors. It allows full utilization of the wells capacity and protects the pump motors from premature wear due to frequent switching on and off.

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Changes in the groundwater levels and regimes in the taiga zone of Western Siberia as a result of global warming

Theoretical and Applied Climatology ◽

10.1007/s00704-021-03879-4 ◽

2021 ◽

Author(s):

Oleg Savichev ◽

Julia Moiseeva ◽

Natalia Guseva

Keyword(s):

Global Warming ◽

Western Siberia ◽

Taiga Zone ◽

Groundwater Levels

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Assessing the response of groundwater quantity and travel time distribution to 1.5, 2, and 3 °C global warming in a mesoscale central German basin

Hydrology and Earth System Sciences ◽

10.5194/hess-24-1511-2020 ◽

2020 ◽

Vol 24 (3) ◽

pp. 1511-1526

Author(s):

Miao Jing ◽

Rohini Kumar ◽

Falk Heße ◽

Stephan Thober ◽

Oldrich Rakovec ◽

...

Keyword(s):

Global Warming ◽

Travel Time ◽

General Circulation ◽

General Circulation Models ◽

Hydrologic Model ◽

Groundwater Model ◽

Groundwater Levels ◽

Ensemble Simulations ◽

Projected Change ◽

German Basin

Abstract. Groundwater is the biggest single source of high-quality freshwater worldwide, which is also continuously threatened by the changing climate. In this paper, we investigate the response of the regional groundwater system to climate change under three global warming levels (1.5, 2, and 3 ∘C) in a central German basin (Nägelstedt). This investigation is conducted by deploying an integrated modeling workflow that consists of a mesoscale hydrologic model (mHM) and a fully distributed groundwater model, OpenGeoSys (OGS). mHM is forced with climate simulations of five general circulation models under three representative concentration pathways. The diffuse recharges estimated by mHM are used as boundary forcings to the OGS groundwater model to compute changes in groundwater levels and travel time distributions. Simulation results indicate that groundwater recharges and levels are expected to increase slightly under future climate scenarios. Meanwhile, the mean travel time is expected to decrease compared to the historical average. However, the ensemble simulations do not all agree on the sign of relative change. Changes in mean travel time exhibit a larger variability than those in groundwater levels. The ensemble simulations do not show a systematic relationship between the projected change (in both groundwater levels and travel times) and the warming level, but they indicate an increased variability in projected changes with adjusting the enhanced warming level from 1.5 to 3 ∘C. Correspondingly, it is highly recommended to restrain the trend of global warming.

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Performance characteristics of a heat pump using renewable transcritical CO2 refrigerant for heating water

International Journal of Low-Carbon Technologies ◽

10.1093/ijlct/ctab009 ◽

2021 ◽

Author(s):

Mohammed Yunus ◽

Mowffaq M Oreijah

Keyword(s):

Global Warming ◽

Heat Pump ◽

Flow Rate ◽

Water Flow Rate ◽

High Energy ◽

Coefficient Of Performance ◽

Heating Water ◽

Fan Speed ◽

Carbon Dioxide Co2 ◽

Full Utilization

ABSTRACT Among non-toxic and inflammable working fluids, carbon dioxide (CO2) proving a possible choice of refrigerant is gaining full status because of its reducing capacity of global warming and ozone depletion. Heat pump (HP) equipment uses energy more rationally to heat water by reducing emissions and global warming caused by conventional refrigerants. HP capability demands an environmentally friendly refrigerant for their full utilization and high energy saving as well to attaining higher coefficient of performance (COP) without much design corrections. CO2 is checked for sustainability to eliminate the standardized refrigerants such as chlorofluorocarbons (CFC) and hydro-CFC. In this work, the performance of CO2 as an alternate refrigerant in HP for heating water at different pressure, flow rates, evaporator fan speed and preheating have been investigated. HP is accommodated with two condensers. The results showed that the increased mass flow rate had increased COP, overall heat transfer (HT) coefficient (U) and HT. However, logarithmic mean temperature difference was decreased for increasing evaporator’s fan speed and pressure. The outlet water temperature (TWO) of second condenser increased with decreasing water flow rate. Improved COP, HT and TWO of HP are observed from the experimental evaluation in case of preheating of water.

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Modelling ecosystem adaptation and dangerous rates of global warming

Emerging Topics in Life Sciences ◽

10.1042/etls20180113 ◽

2019 ◽

Vol 3 (2) ◽

pp. 221-231 ◽

Cited By ~ 4

Author(s):

Rebecca Millington ◽

Peter M. Cox ◽

Jonathan R. Moore ◽

Gabriel Yvon-Durocher

Keyword(s):

Climate Change ◽

Global Warming ◽

Diffusion Rate ◽

Individual Species ◽

Genetic Evolution ◽

Rates Of Change ◽

Rapid Climate Change ◽

Warming Climate ◽

Intraspecies Competition ◽

High Trait

Abstract We are in a period of relatively rapid climate change. This poses challenges for individual species and threatens the ecosystem services that humanity relies upon. Temperature is a key stressor. In a warming climate, individual organisms may be able to shift their thermal optima through phenotypic plasticity. However, such plasticity is unlikely to be sufficient over the coming centuries. Resilience to warming will also depend on how fast the distribution of traits that define a species can adapt through other methods, in particular through redistribution of the abundance of variants within the population and through genetic evolution. In this paper, we use a simple theoretical ‘trait diffusion’ model to explore how the resilience of a given species to climate change depends on the initial trait diversity (biodiversity), the trait diffusion rate (mutation rate), and the lifetime of the organism. We estimate theoretical dangerous rates of continuous global warming that would exceed the ability of a species to adapt through trait diffusion, and therefore lead to a collapse in the overall productivity of the species. As the rate of adaptation through intraspecies competition and genetic evolution decreases with species lifetime, we find critical rates of change that also depend fundamentally on lifetime. Dangerous rates of warming vary from 1°C per lifetime (at low trait diffusion rate) to 8°C per lifetime (at high trait diffusion rate). We conclude that rapid climate change is liable to favour short-lived organisms (e.g. microbes) rather than longer-lived organisms (e.g. trees).

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