Gas turbine Definition and 67 Threads

Hello everyone, I was wondering what would the impact be if an existing gas turbine made to run in air at atmospheric pressure was run in an atmosphere of helium (let's say in a closed loop heated through a heat exchanger). How would the power output and efficiency be impacted, and what would...

-Gas turbines, as a general rule require very high rotational speeds (tens of thousands of rpm for small tabletop models) in order to reach a self sustaining speed. Gas turbines are also limited to efficiency based on the pressure ratio generated by the compressor. -Question: What is...

I created a crayon drawing to aid the discussion below: Basically if you have a blower of low pressure, and you blow it through a tube which has a very hot center, when the heat is added to the air, does the pressure of the air increase after passing by the fire, or is that impossible since...

Hello, I am trying to solve a problem about an open Gas Turbine. The given information would be: - An open gas turbine draws in air from the surroundings having the m, cp, T1 and constant kL with the next values: , - The air flow is heat over natural gas supplied: - The pressure ratio is 𝜋...

I would very much appreciate anyone to cast their eye over my attempt at solving this problem which I've been struggling with the past few days. Many thanks in advance. Assuming that: energy input from open-type regenerative feed heater pump is negligible no energy is lost the heater pressure...

Hello Gents, I am very confused about the working principle of gas turbines. I understand that air is first compressed in a compressor to obtain high pressure air at the inlet of turbine, but before air is introduced to the turbine, first it has to be heated to very high temperatures through...

Hi, I was attempting another turbomachinery question and am struggling with a few concepts. The question is: "A single stage gas turbine for power generation is designed for the following overall duty: - Power output is 4.2 MW, and mass flow rate is 70 kg/s - Inlet stagnation pressure = 3 bar...

Summary:: NO TEMPLATE BECAUSE THIS HOMEWORK PROBLEM WAS MISPLACED IN A REGULAR FORUM Cant do part c, using the steady flow equation I am confused how to continue. Please help! Mainly confused as to what heat transfer loss represents in the steady flow equation and where to go to find the...

I'm looking for advice on how much power is required to compress air in a gas turbine engine - parameterised by degree of compression and mass flow. Normal gas turbine engines have exhaust turbine(s) on the same shaft as the air compressors. They bleed some of the exhaust energy to drive the...

In a gas turbine engine(in aircrafts), why doesn't the gas after expansion move backwards towards the compressor? .How is it that it expands away from the compressor(rotating the turbine blades)? Will the pressure of air at the end of the compressor before the combustion chamber be higher than...

I concede that the anvil of experiment is a beloved companion of mine but assert I can stop anytime I like. When epistemically possible, the words "It can't be done" translate directly to "I don't know how". I love a challenge and relish the pursuit of solution, practical or otherwise. The...

Hi, As per my observation and experience, when we use evaporative cooler to cool the inlet air to the gas turbine, the compressor discharge pressure (i.e PCD or P3) rises. As, the temp. of the inlet air drops and the mass flow increases due to the increase in density, I believe the discharge...

Hey Mech Eng Forum, I'm currently examining the performance on gas turbine and wondering: How is the performance of gas turbines (Primarily thermal efficiency and net-work output) influenced by the pressure ratio and temperature constraints? Additionally, what is the benefit of 2 stage...

Hi all, I need to estimate the mechanical work I can recover from expanding hot air through a gas turbine. So far I am using the equation below, where Wrev is my ideal isentropic work, s the number of stages, n = k = ratio of specific heats, R gas constant, T1 is the inlet Temperature, Pin the...

Hello, I am currently working on a storage project which allows me to decouple the compressor from the expander of a gas turbine. (see image link below) The reason I use a gas turbine is to reheat the air which was cooled after being compressed. As you can imagine there is a efficiency loss...

Hello all! I am going out on a limb here looking for information as I am unable to find the answers scouring the internet. Essentially I want to know how a person would go about getting a job working with Gas Turbine Tuning and Controls? I've got an engineering background, lots of gas turbine...

I want do thermal and structural analysis (Failure) on gas turbine blade. So what how to begin. Kindly help me.

Hello everyone, My name is Davey and I am studying aerospace engineering at Coventry University in England. I adore physics in all forms but my true passion is aerospace (obviously) and more specifically, powerplants and their applications. Anyway, I joined really, to answer someones...

Homework Statement Homework Equations N/A The Attempt at a Solution I am confused what 5-5b and 5b-6 represent in the above TS diagram. I know that 1-2 is compression, 2-3 is cooling, 3-4 is compression and 4-5 is regeneration (since these are indicated in the block diagram) but as for 5-5b...

Hi Everyone, So I seem to have many problems understanding the Psychrometric chart and its physical meaning. First of all, I would be so thankful if you could introduce me a source which can be useful to physically and fundamentally understand the dew point, effect of pressure, humidity... and...

Hey I've been thinking of this idea for a while, If I had a small boat with a home made gas turbine engine on it to power it solely with thrust. If I put an afterburner on it and nozzle; and had a small intake for water that filtered out all of the crud. Would it be possible to generate more...

Hi I am new member ( mechanical engineer student ) , and the college just add a new course which is Turbo machinery , any way the teacher is new to the course & the quality of our teacher is not that good so , I was having a question and ask him but didnt get much from him so here I am ^^When...

hi friends, I've used the following equation in Thermodynamics: an engineering approach(Cengel) for calculating exergy efficiency of compressor. In fact, for an adiabatic compressor with negligible kinetic and potential energies, the second-law(exergy) efficiency becomes...

hi friends, I am working EES software for thermodynamic lesson,I am analyzing second law efficiency(exergy efficiency) and exergy analysis for all components of gas turbine cycle. Now I have a problem,exergy efficiency of turbine decrease with increasing before temperature,why? As you know...

hello. I have to design and test a gas turbine that uses pressurised air as a project. however the problem is, I don't know where to start. can anyone please help me? do I start with the blades or the housing? I have seen some videos on youtube, but this is a university project and I think its...

Hi all, I am not able to physically understand the term "load" when we refer to Single Shaft Gas Turbine engines used for power generation purposes. What is causing the torque on the Gas Turbine (GT) to change? Again how the speed is maintained constant while the torque is varied? For a single...

Can anyone tell me what is alarm loging? I m working on a gas turbine,there is a problem in its controller.my instrument fellow told me that alarm loging is not working,I m from mechanical engineering background. Thanks in advance

Hi, Just wondered why the rotor of a gas turbine (generally inside) is not made stationary and the casing (drum that surrounds the rotor) made to rotate...kind of reversed gas turbine... One limitation i thought about was the combustion can placement... Any other views as to why we don't see...

Hi, I went through many resources but I am not able to understand as to what stall/surge means for an axial compressor means. I am not able to imagine or correlate it. I want to physically understand what happens in a compressor when it is stalled. For eg: Can a ceiling fan stall when the angle...

My classmates and I are working on a senior design project where we optimize a baseline turbofan for supersonic cruise. We are a little confused about when to use polytropic vs isentropic efficiencies. I have read to begin with isentropic, however is there anyone who could explain a little more...

I'm doing a survey on the topic of "gas turbine blades stress analysis" to see what areas are not focused on in this subject. I've found that not many people talk about the aerodynamic forces on the blade. Am I missing something, are they included in the calculation or are they too small to...

barring a few exceptions i read that it is because they aren't effecient at small scale. can someone elaborate on that? also, would even smaller turbines need some time to start up?

Is this gas turbine engine compressor discharge air temperature calculation relatively accurate? Problem: Calculate the compressor discharge air temperature in ºF of the following gas turbine engine compressor core specifications. Gas Turbine Engine Compressor Core Specifications...

Homework Statement An ideal simple gas turbine has a compression ratio of 5. What is its Homework Equations c=r(γ-1/γ) η=1-(1/c) The Attempt at a Solution I'm stuck, I think I need to use the above equations and possibly more. I just don't know how to find a value for the ratio of...

Thank you Regards

Gas turbine fuel/air ratio & cooling, help please! Hello Dear Colleagues, I am doing a gas turbine project and I wonder why we use cooling air instead of decreasing the fuel/air ratio after getting the following results from my gas turbine thermodynamic model. I have a mechanism in my model...

I am doing research and was curioius as to how I would obtain useful numbers for efficiencies from the following information, concerning a CHP aero derivative turbine, Power KW = 43822 Heat Rate LHV KJ/kWH = 8980 From this, can I say that if I ran the machine for an hour I would use...

Homework Statement a gas turbine is designed to produce 3000hp when using air at a maximum inlet temperature of 650k and assuming a heat loss of 70 kj/s. if the exhaust temperature is desired to be no greater than 200 degrees celsius, determine the mass flow rate of air required. Homework...

Guys, I was reading about Turbofan and somewhere while browsing Defence Turbofan engines I came across Booster stages, but I didn't find any description or what are booster stages in Gas Turbine (Axial Compressor)

Hello, I`m working on a mathematical model of a gas turbine and I need good compressor maps, especially function of efficiency vs. pressure ratio, inlet temperature, mass flow etc I`ve been looking for this for few days, but can`t find anything interesting. Do you know where I can...

Homework Statement A gas turbine power plant operates on the regenerative Brayton cycle as shown in the figure. Compression occurs in two stages, with interstage cooling, and expansion in the turbine likewise occurs in two stages, with interstage reheating. The cycle operates between the...

We all know the constant volume combustion engine acts as a kind of internal combustion engine that is used in the car and truck extremely widely. The cycle is called Otto cycle. I also heard the constant volume combustion gas turbine engine was proposed many years ago and developed a few ones...

why convergent rather than divergent? is this to maintain the constant air velocity. Can someone explain this better to me. Would be helpfull

Hi I have been trying to figure out the force experienced by individual components of a gas turbine engine. Generally, the thrust of the engine is defined / calculated as the change in the momentum of the fluid. Usual formula is mass flow X (C_jet - C_intake) + the pressure difference in...

In order to test the performance of a specific engine, is it necessary to find a design point? If so could anyone tell me how to find the design point for gas turbine engine and suggest any useful materials that gives good information about Design point performance. Thank you!

Hi guys, Currently doing a Final Year Project on a gas turbine and steam turbine energy plant combinate, and was wondering if anyone knows where i could find some data on a specific gas turbine with all pressures, temperatures and efficiencies? just so i can verify my calculated results Thanks

I was on an easyjet flight this morning and noticed a distinct and pronounced rattling, clicking noise coming from one of the engines. Not being a very good flier at the best of times (despite working in the aerospace sector) I was pretty worried. When the engines spooled up I was also sure I...

Homework Statement Air enters a gas turbine at 1600K and exits at 100kPa and 830K. The turbine efficiency is 85%. Determine the turbine inlet pressure? Homework Equations (I used 3 different methods and got a similar answer. I just don't understand if I was correct in assuming...

Hi friends; I have Saturn 1100 and centaur 4500 two shaft gas turbines from solar INc. I want to know that what relationship of following parameters 1. Compressor discharge pressure and fuel flow 2. How i calculate the SFC? 3. What effect of LHV on SFC? 4. How i calculate the Heat rate? If...

Homework Statement I'm having difficulty obtaining an accurate value possibly due to unit conversions. Homework Equations r_m=mdot/(2*pi*U*N) r_m=mean radius, ft mdot=mass flow rate, lbm/s U= blade velocity, ft/s N= RPM The Attempt at a Solution I know that I have to convert Rpm...