The volume of an open expansion tank should be the double of the estimated expansion volume in the system. The pressure is limited by the highest location of the tank. Open expansion tankĪn open expansion tank is only relevant for Low Pressured Hot Water - LPHW - systems. To avoid the expansion building up a pressure in the system exceeding the design pressure, it is common to led the expanding fluid to a tank - open or or closed. The expansion of water heated from 7 oC to 100 oC is approximately 4%. P loss = pressure loss (Pa (N/m 2), psi (lb/ft 2)) Minor pressure loss due to fittings as bends, elbows, valves and similar may be calculated as: I = major pipe friction resistance per length of pipe (N/m 2 per meter pipe)įriction resistance values for the actual pipes and volume flows may be obtained from the special charts made for the pipes or tubes. The major pressure loss due to friction may alternatively be expressed as P 2 = minor pressure loss due to fittings ( N/m 2) P 1 = major pressure loss due to friction ( N/m 2) P t = total pressure loss in the system (N/m 2) The total pressure loss in a hot water piping system can bed expressed as Ρ 2 = density of water at return temperature (kg/m 3) 5. Ρ 1 = density of water at flow temperature (kg/m 3) G = acceleration of gravity = 9.81 (m/s 2) H = height between center of boiler and center of radiator (m) P = circulating pressure available (N/m 2) The circulating force in a gravity system can be calculated as Ρ = density of water at pump (kg/m 3) (1000 kg/m 3 at 5 oC, 958 kg/m 3 at 100 oC)įor low pressure pumped circulation systems - LPHW (3) can be approximated toįor low pressure pumped circulation systems - LPHW a head 10 to 60 kN/m 2 and major pipe friction resistance of 80 to 250 N/m 2per meter pipe is common.įor high pressure pumped circulation systems - HPHW a head 60 to 250 kN/m 2 and major pipe friction resistance of 100 to 300 N/m 2per m pipe is common. H 1 = enthalpy flow water (kJ/kg) (4.204 kJ/kg. Sizing PumpsĬapacity of circulation pumps can be calculated as Heaters with correct ratings must be selected from manufacturing documentation. X = margin for heating up the room - common values in the range 0.1 to 0.2 Radiators and room heaters rating can be calculated as The correct boiler must be selected from manufacturing documentation. X = margin for heating up - it is common to use values in range 0.1 to 0.2 In addition heat loss caused by ventilation and infiltration of outdoor air must be calculated. Make pipe scheme and calculate pipe sizesĬalculate transmission heat losses through walls, windows, doors, ceilings, floors etc.Select type, size and duty of circulation pump.The advantages of these systems for heating extra-long pipelines transporting oil, gas, water and other liquids are explored.The design of a hot water heating system may follow the procedure as indicated below: In closing, three types of electro heating skin-systems are presented and the main features of skin heating systems are considered. Research is presented which is aimed at designing a logistics system for X Gas Company to ensure efficient distribution of liquefied petroleum gas, which begins with the ordering process and ends with the placement of stations in Istanbul-Turkey, taking into account the storage, preparation, loading and delivery operations of X Gas Company. Multi-criteria decision making techniques, fuzzy AHP and fuzzy ANP methods are used for evaluation and the results of both algorithms are compared. Heating Systems: Design, Applications and Technology first discusses the development of different types of district heating systems, highlighting the main features of low temperature district heating and discussing its potential for supplying decarbonised heat.Īs buildings consume about 40% of the world’s annual energy consumption globally, the authors focus on the evaluation of residential heating system alternatives using fuzzy numbers. Series: Electrical Engineering Developments
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