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Untapped geothermal sites in the United States havethe estimated potential to deliver
(a) Assuming the brine has the properties of water, determine the required brine flow raw, the requiredeffectiveness of the heat exchanger, and therequired heat transfer surface area. The overall heat transfer coefficient is
(b) Over time, the brine fouls the heat transfer surfaces, resulting in
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- (a) Based on the analysis of steam power plant having condenser, why thermal efficiency of power plant is high in cold region and less in warm region. Explain with the help of T-s diagram (b) Outline why value of TTD is negative in scenario where we have high pressure heater. Explain with the help of T-L diagram (c) In cogeneration having back pressure turbine process heater replaces condenser, outline the difference between process heater and condenserarrow_forwardA steam power plant is located in an industrial park owned by the BERTSCHenergy Group. This is used to generate electricity and steam. A mass flow of 80 kg /s with a steam content of 77% at a pressure of 0.0075 MPa flows into a condenser of the steam pawer plant. In a colecting basin with a volume of 20 m, the condensate flows together at a temperature of 50*C. it gives off the rest of the heat completely to the environment. The ambient temperature is a constant 24 *C. ispecific heat capacity of water c= 4.18 ki / (kg K) a) Which heat flow has to be dissipated so that there is saturated liquid at the outlet of the condenser? Enter the result in MW with 2 decimal places. Replyt b) Calculate the specific entropy difference of the condensate in the collecting basin and enter it in kl / (kg " K) with 2 decimal places Replytarrow_forwardThe purpose of the regenerative heat exchanger is to essentially recycle the heat rejected in step (B) as heat absorbed in step (D). Show why this works for the case of a general working fluid with heat capacity, Cv(T). The Stirling engine (invented in 1816 by Robert Stirling) is a heat engine that produces work through cyclic compression and expansion of a gaseous working fluid, such as hot air. An idealized cyclic process, aptly named the Stirling Cycle, for such an engine consists of four steps: (A) isothermal expansion at the hot reservoir temperature, Th, (B) isochoric (constant volume) heat rejection to a regenerative heat exchanger, (C) isothermal compression at the cold reservioir temperature Te, and (D) isochoric heat absorption from the regenerative heat exchanger back to the initial state.arrow_forward
- It is proposed to design and develop a Rankine cycle Steam Power Plant in which steam at 80 barand 500 oCis supplied to the turbine which exhausts at a pressure of 0.11 bar into a condenser. Condensate from the condenser is returned to Steam Generator (Boiler) by a Feedwater Pump. The processes in the turbine and pump can be assumed to be reversible adiabatic. In addition, pressure and temperature drops can be neglected throughout the cycle. Sketch the T-s diagram for this cycle and calculate the following performance parameters:i) Cycle Thermal Efficiency ii) Work Ratioiii) Specific Steam Consumptioniv) Condenser Heat Loadv) Mass flow rate of steam to generate a net power output of 40 Megawatts (MW).vi) Mass flow rate of cooling water required for the condenser if the cooling water inlettemperature is 26 oC and its outlet temperature is limited to 40 oC. The specific heat capacityof the cooling water is 4.18 kJ/kg K.viii) The total amount of sensible heat in kW supplied to the…arrow_forwardIn a binary geothermal power plant, the working fluid isobutane is to be condensed by air in a condenser at 75°C (h = 255.7 kJ/kg) at a rate of 0.95 kg/s. Air (cp= 1005 J/kg. C) enters fg the condenser at 21°C and leaves at 29°C. The heat transfer surface area based on the isobutane side is 26.9 m. What is the overall heat transfer coefficient (W/m².k)? Use the LMTD method and assume a correction factor of 0.95 Select one:arrow_forwardSuppose that the regenerative heat exchanger is only 80% efficient, i.e., only 80% of theheat exhausted in step (B) is absorbed in step (D). For an ideal gas working fluid (Cv = 5/2 R, R = 8.3145 J/mol K) operating with the heat reservoirs at Th = 400 K and Tc = 300 K, determine how much work per mol of working fluid is needed to supplement the regenerative heat exchanger in step (D) and ensure that the cycle is completed. What is the new ηcycle in light of this additional work requirement? (the answer does not need to be numeric)arrow_forward
- A gas turbine exhaust stack cooler drops the gas temperature from 1020oF to 605°Fby means of a water cooling coil. Cooling water enters the coil at 65°F and leaves,after a counter-flow passage, with a temperature of 190°F. If cp for the gas is 0.26Btu/lb.F, calculate the overall heat transfer coefficient for an exchanger area of2000 ft2, Btu/hr.ft2.F.A. 19.94 B. 29.94 C. 39.94 D. 49.94arrow_forward. The exhaust gas regenerator (counter-flow heat exchanger) for a gas turbinehandles 1.9 kg/sec of air from its compressor and heats it by means of 2.2 kg/secof hot exhaust gas. Exhaust gas enters the regenerator at 596°C and leaves at312°C. Compressed air enters the regenerator at 220°C. For this temperaturerange a constant pressure specific heat for the exhaust has may be estimated at1090 J/kg-°C. Assume no heat transfer other than between the generator fluids.Determine the log mean temperature difference for the exchanger, °CA. 16.98 B. 26.98 C. 36.98 D. 46.98arrow_forwardAs shown below, a refrigeration cycle condenses a flow of ammonia from a saturated vapor at 4 barto a saturated liquid. The entering volumetric flow rate of the ammonia is 0.1 m3/s. The ammonia functions asthe cold reservoir for the refrigeration cycle, and the hot reservoir is at 25 ∘C. A faded specification sheet for therefrigeration cycle reads that the required power input is 35 kW.(a) Is this cycle possible? Why or why not?(b) If the cycle is impossible, how much work input is required to make the cyclearrow_forward
- If the net power output of the cycle is 100 MW, and that the working fluid enters the turbine as saturated steam at P= 8.00 MPa and exist the condenser as saturated liquid at P=8kpa Determine: a) the terminal efficiency (%) b) The mass flow rate of the steam , kg/s C) The rate of heat transfer to the working fluid as it passes through the boiler, KW D) The heat rejected by the working fluid as it passes through the condenser, kW. e) The mass flow rate of the cooling water, kg/s. N.B ( the cooling water enters the condenser at 15°C and leaves at 35°C)arrow_forwardA boiler has a mass flow rate of 3 tons/hour of feed water at a temperature of 28 C and a pressure of 1 atm. This water is pumped to a pressure of 30 atm assuming a constant temperature. Pump efficiency is 90%. The water leaving this pump is heated in an Economizer heat exchanger to its saturation point temperature in the saturated water phase? What is the rate of heat supplied by the Economizer to heat the pump exit feedwater to the above conditionsarrow_forwardOcean thermal energy conversion (OTEC) plants use the temperature difference in the ocean (80°F at the surface and 40°F at 2000 ft. depth) in a Rankine cycle to generate electricity. Ammonia is the working fluid. Ammonia is boiled using the 80°F surface water, and condensed against the 40°F deep water, which is pumped to the surface. Very large heat exchangers are required, due to the small LMTDs and the low plant thermal efficiency (2.5%). The heat exchangers will comprise 40 % of the plant cost. In order to reduce the condenser cost, we will evaluate the condenser tube material savings provided by the use of a vertical fluted "Gregorig" condensing surface. The reference smooth tube condenser design uses 1.0 in. I.D. aluminum tubes, 0.062 in. wall x 30 ft. long. Sea water flows on the tube-side at 8 ft/sec. Ammonia condenses at 50°F on the outer surface of the vertical tubes with 4Tvs = 4°F. The ammonia properties at 48°F are: p= 39.1 lbm/ft³, k₁= 0.307 Btu/hr-ft- °F, и 1.426 × 10-2…arrow_forward
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