A Formal Representation of Conjugate Verbs for Function Modeling

2021 ◽  
pp. 1-34
Author(s):  
Ahmed Chowdhury ◽  
Lakshmi Narasimhon Athinarayana Venkatanarasimhan ◽  
Chiradeep Sen
Keyword(s):  
Mechanical Design ◽  
System Level ◽  
Formal Representation ◽  
Geothermal Heat ◽  
Operating Modes ◽  
Heating And Cooling ◽  
Geothermal Heat Pump ◽  
Level Function ◽  
Modal Reasoning ◽  
Functional Features

Abstract Modern design problems often require multi-modal, reconfigurable solutions. Function modeling is a common tool used to explore solutions in early mechanical design. Currently, function modeling formalisms minimally support the modeling of multi-modal systems in a formal manner. There is a need in function modeling to capture multi-modal system and analyze the effects of control signals and status signals on their operating modes. This paper presents the concept of functional conjugacy, where two function verbs or functional subgraphs are topological opposites of each other. The paper presents a formal representation of these conjugate verbs that formally captures the transition from one mode of operation to its topological opposite based on the existence of, or the value of, signal flows. Additionally, this paper extends functional conjugacy to functional features, which supports conjugacy-based reasoning at a higher level of abstraction. Through the example of a system-level function model of a geothermal heat pump operating in its heating and cooling modes, this paper demonstrates the ability to support modal reasoning on function models using functional conjugacy and illustrates the modeling efficacy of the extended representation.

A Formal Representation of Conjugate Verbs in Function Modeling

2020 ◽  
Author(s):  
Ahmed Chowdhury ◽  
Lakshmi N. A. Venkatanarasimhan ◽  
Chiradeep Sen
Keyword(s):  
Causal Reasoning ◽  
Operating Mode ◽  
Flow Property ◽  
System Level ◽  
Formal Representation ◽  
Geothermal Heat ◽  
Design Problems ◽  
Geothermal Heat Pump ◽  
Level Model ◽  
Function Models

Abstract Many modern and innovative design problems require multi-modal, reconfigurable solutions. Function modeling is a common tool used to explore solutions in early stages of mechanical engineering design. Currently, function structure representations do not support the modeling of formally-defined reconfigurable function models. There is a well-established need in function modeling to dynamically capture the effects of state change of a flow property on the operating mode of the system. This paper presents a formal representation to capture the duality of specific functions, and illustrates it through three verbs that shift from one mode of operation to its logical and topological opposite, based on the existence of, or the value of a signal from, an input flow. Additionally, an approach to extend these functions to function features, in order to support physics-based reasoning on the interactions between flows is also presented. Through the example of a system-level model of a geothermal heat pump operating in its heating mode, the representation demonstrates the ability to support causal reasoning on functional modes of systems, provides quantitative reasoning on the efficiency of those modes, and illustrates the modeling efficacy of the extended representation.

scholarly journals The GRETA project: the contribution of near-surface geothermal energy for the energetic self-sufficiency of Alpine regions

2017 ◽  
Vol 6 (1) ◽  
Author(s):  
Alessandro Casasso ◽  
Bruno Piga ◽  
Rajandrea Sethi ◽  
Joerg Prestor ◽  
Simona Pestotnik ◽  
...  
Keyword(s):  
Geothermal Energy ◽  
Primary Energy ◽  
Economic Activities ◽  
Geothermal Heat ◽  
Geothermal Resources ◽  
Near Surface ◽  
Alpine Regions ◽  
Heating And Cooling ◽  
Geothermal Heat Pump ◽  
Alpine Space

The Alpine regions are deeply involved in the challenge set by climate change, which is a threat for their environment and for important economic activities such as tourism. The heating and cooling of buildings account for a major share of the total primary energy consumption in Europe, and hence the energy policies should focus on this sector to achieve the greenhouse gas reduction targets set by international agreements. Geothermal heat pump is one of the least carbon-intensive technologies for the heating and cooling of buildings. It exploits the heat stored within the ground, a local renewable energy source which is widely available across the Alpine territory. Nevertheless, it has been little considered by European policies and cooperation projects. GRETA (near-surface Geothermal REsources in the Territory of the Alpine space) is a cooperation project funded by the EU INTERREG-Alpine Space program, aiming at demonstrating the potential of shallow geothermal energy and to foster its integration into energy planning instruments. It started in December 2015 and will last three years, involving 12 partners from Italy, France, Switzerland, Germany, Austria, and Slovenia. In this paper, the project is presented, along with the results of the first year of work.

scholarly journals Efficiency of Passive Utilization of Ground “Cold” in Adaptive Geothermal Heat Pump Heating and Cooling Systems (AGHCS)

2016 ◽  
Vol 77 ◽  
pp. 06008
Author(s):  
G.P. Vasilyev ◽  
V.F. Gornov ◽  
M.V. Kolesova ◽  
A.N. Dmitriev ◽  
V.G. Silaeva
Keyword(s):  
Heat Pump ◽  
Geothermal Heat ◽  
Cooling Systems ◽  
Heating And Cooling ◽  
Geothermal Heat Pump

scholarly journals An Investigation on the Feasibility of Near-Zero and Positive Energy Communities in the Greek Context

Smart Cities ◽  
2020 ◽  
Vol 3 (2) ◽  
pp. 362-384 ◽  
Author(s):  
Vasileios Sougkakis ◽  
Konstantinos Lymperopoulos ◽  
Nikos Nikolopoulos ◽  
Nikolaos Margaritis ◽  
Paraskevi Giourka ◽  
...  
Keyword(s):  
Renewable Energy ◽  
Pump Energy ◽  
District Heating ◽  
Energy Performance ◽  
Positive Energy ◽  
Zero Energy ◽  
Geothermal Heat ◽  
Energy Technologies ◽  
Heating And Cooling ◽  
Geothermal Heat Pump

Near Zero Energy and Positive Energy communities are expected to play a significant part in EU’s strategy to cut greenhouse gas emissions by 2050. Within this context, the work presented in this paper aims to investigate the feasibility of: (a) a new-built positive energy neighborhood; and (b) the retrofit of an existing neighborhood to near zero energy performance in the city of Alexandroupolis, Greece. Proposed measures involve the rollout at the community scale of renewable energy technologies (PV, geothermal heat pump), energy efficiency (fabric insulation, district heating and cooling networks) and storage systems (batteries). A parametric analysis is conducted to identify the optimum combination of technologies through suitable technical and financial criteria. Results indicate that zero and near zero emissions targets are met with various combinations that impose insulation levels, according to building regulations or slightly higher, and consider renewable energy production with an autonomy of half or, more commonly, one day. In addition, the advantages of performing nearly zero energy retrofit at the district, rather than the building level, are highlighted, in an attempt to stimulate interest in community energy schemes.

scholarly journals Modeling of an Air Conditioning System with Geothermal Heat Pump for a Residential Building

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Silvia Cocchi ◽  
Sonia Castellucci ◽  
Andrea Tucci
Keyword(s):  
Heat Pump ◽  
Air Conditioning ◽  
Residential Building ◽  
Heat Pumps ◽  
Geothermal Heat ◽  
Air Conditioning System ◽  
Heating And Cooling ◽  
Ground Source ◽  
Geothermal Heat Pump ◽  
Geothermal Plant

The need to address climate change caused by greenhouse gas emissions attaches great importance to research aimed at using renewable energy. Geothermal energy is an interesting alternative concerning the production of energy for air conditioning of buildings (heating and cooling), through the use of geothermal heat pumps. In this work a model has been developed in order to simulate an air conditioning system with geothermal heat pump. A ground source heat pump (GSHP) uses the shallow ground as a source of heat, thus taking advantage of its seasonally moderate temperatures. GSHP must be coupled with geothermal exchangers. The model leads to design optimization of geothermal heat exchangers and to verify the operation of the geothermal plant.

scholarly journals Hybrid Solar Geothermal Heat Pump System Model Demonstration Study

2022 ◽  
Vol 9 ◽  
Author(s):  
Yu-Jin Kim ◽  
Libing Yang ◽  
Evgueniy Entchev ◽  
Soolyeon Cho ◽  
Eun-Chul Kang ◽  
...  
Keyword(s):  
Power Consumption ◽  
Ambient Temperature ◽  
Heat Pump ◽  
Geothermal Heat ◽  
Pump System ◽  
Heat Pump System ◽  
Source Temperature ◽  
Heating And Cooling ◽  
Geothermal Heat Pump ◽  
Polygeneration System

In this paper, the development and demonstration of a hybrid solar geothermal heat pump polygeneration system is presented. The poly-generation system has been designed, modeled, and simulated in TRNSYS software environment. Its performance was assessed followed by installation and demonstration at a demo site in Cheongju, Korea. The space heating and cooling load of the building is 13.8 kW in heating mode at an ambient temperature of −10.3°C and 10.6 kW in cooling mode at an ambient temperature of 32.3°C. The simulation data were compared with the field demo data using ISO 13256. The results showed that the model data compare well with the demo data both in heating and cooling modes of operation. At a source temperature of 16.7°C, the heat pump lab performance data-based COPc shows 9.9, while demonstration COPc shows 10.3, thus, representing 4.3% relative error. The heat pump source temperature decreased by 4.0°C from 20.9°C to 16.9°C due to ground heat exchanger coupling and resulted in a COPc increase by 13.3% from 8.5 to 9.8. When compared at the design conditions (outside temperature of 32.3°C), the TRSNYS model overestimated the demonstration site data by 12%, 9.3 vs. 8.1 kW with power consumption of 3.1 vs. 2.2 kW. The hybrid polygeneration system power consumption decreased by 1.2 kW when ambient temperature decreased from 35°C to 25°C.

scholarly journals THERMAL PERFORMANCES OF DIFFERENT TYPES OF UNDERGROUND HEAT EXCHANGERS

2020 ◽  
Vol 2 (2) ◽  
pp. 10-50
Author(s):  
Abdeen Omer
Keyword(s):  
Heat Pump ◽  
Alternative Energy ◽  
Renewable Energy Sources ◽  
Stratospheric Ozone ◽  
Performance Standards ◽  
Montreal Protocol ◽  
Geothermal Heat ◽  
Heating And Cooling ◽  
Ground Source ◽  
Geothermal Heat Pump

Globally buildings are responsible for approximately 40% of the total world annual energy consumption. Most of this energy is for the provision of lighting, heating, cooling and air conditioning. An increase in awareness of the environmental impact of CO2, NOx and CFCs emissions triggered a renewed interest in environmentally friendly cooling and heating technologies. Under the 1997 Montreal Protocol, governments agreed to phase out chemicals used as refrigerants that have the potential to destroy stratospheric ozone. An approach isneeded to integrate renewable energies in a way to achieve high building performance standards. However, because renewable energy sources are stochastic and geographically diffuse, their ability to match demand is determined by the adoption of one of the following two approaches: the utilisation of a capture area greater than that occupied by the community to be supplied, or the reduction of the community’s energy demands to a level commensurate with the locally available renewable resources. Ground source heat pump (GSHP) systems (also referred to as geothermal heat pump systems, earth-energy systems and GeoExchange systems) have received considerable attention in recent decades as an alternative energy source for residential and commercial space heating and cooling applications. The GSHP applications are one of three categories of geothermal energy resources as defined by ASHRAE and include high-temperature (>150°C) for electric power production, intermediate temperature (<150°C) for direct-use applications and GSHP applications (generally (<32°C). The GSHP applications are distinguished from the others by the fact that they operate at relatively low temperatures.

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