Questions tagged [diesel]

34 questions
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Why do some diesel engines run on diesel fuel and others on fuel oil?

Trucks and smaller vehicles with diesel engines run on diesel fuel which looks more or less like kerosene - less flammable than gasoline, low viscosity liquid. However larger diesel engines like this 120 thousand horsepower marine engine have more…
sharptooth
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Why do steam and diesel engines have differing cylinder configurations?

Consider a fixed steam engine, such as in a Lancashire cotton mill or pumping in a Cornish mine. Then consider a fixed diesel engine such as a large generator or ship's engine. Why does the steam engine have one or two large cylinders with long…
Paul Uszak
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Does a diesel-like (ignition by compression) engine running on gaseous fuel exist?

I think, it could lead to, for example, very environment friendly and very efficient urban traffic. But I also think, it required very precise part construction. Do such things exist? At least in plan? Extension: Clarification added, waiting for…
peterh
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6
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Limitations of the cut-off ratio in real-world diesel engines

In an ideal diesel cycle, the cut-off ratio is set by the maximum gas temperature after combustion. That's all fine and good, but in a real-world engine what controls the cut-off ratio, and what are the limits to its flexibility? I feel like it must…
Murenrb
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6
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3 answers

Three-phase versus single-phase operation of a generator

My generator (a Fermont MEP-803A, 4 cyl diesel, 10kW rated) can run in three distinct modes: Single-phase 120V, in which one terminal is hot, and another is neutral Single-phase 120V/240V, in which two terminals are hot, and another is neutral. The…
5
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1 answer

In a diesel engine, does more heat leave the engine through the tailpipe or the radiator?

Diesel exhaust is hot, and there's a lot of it. Diesel radiators also get pretty hot. In a typical diesel engine, which one is dissipating more heat? EDIT: In response to a request for specificity below, I am specifically interested in heat losses…
5
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1 answer

How long can UK diesel be stored?

We have standby diesel generators that are only run a few times a year. How long can we reasonably keep the diesel stored on site before using or disposing of it? It is accepted that there is a finite shelf life particularly after the UK has started…
dhewett
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1 answer

Can a water-pump pump diesel?

After some research, I found that diesel is my choice of fuel. Now I need a way to pump it to the engine. My main constraint is price. So my question is can I use a water pump like one of these, to pump the diesel?
Dat Ha
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3
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Inerting system for biodiesel tanks?

I have an interesting problem. We have an off-grid house that uses mostly solar + microhydro + batteries for most of energy needs (which include heatpump-based heating). However, we do need to run a diesel generator for about a month a year during…
Cyberax
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Preheating Diesel before injection?

Significant amount of heat is lost from an engine by various means, so to recoup the energy, is it possible to increase efficiency via heating of diesel fuel prior to injection using waste engine heat in passenger cars similiar to marine diesels?…
3
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2 answers

Balancing Locomotive Power

My first post here. I'm curious about how power is balanced in multiple diesel-electric locomotives. I understand to that two locos can be ganged in terms of controls, to set speed etc, so that one set of driver controls manages the whole pulling…
Steve Taylor
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Why is soot produced in diesel exhaust, since diesel runs lean?

Since diesel runs lean, why is soot produced in diesel exhaust? Soot is carbon particles due to incomplete combustion. But, since diesel runs lean with plenty of oxygen, why does this happen?
ergon
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Generator prime movers vs. motor starting voltage drop: why does it matter what's spinning the alternator?

I was playing around in Cummins' GenSize tool with an example 5HP fire pump load to try to get an idea for just how large a generator would be needed to start a small fire pump, and found something very interesting. As it turns out, while a 40kW…
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1 answer

What are the limiting factors on diesel engine compression ratios?

Higher compression ratios in internal combustion engines generally improve the engine's fuel efficiency. But diesel engines don't seem to go above a ratio of 25 or so. What is the limiting factor for the compression ratio in diesel engines? (For…
2
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3 answers

Why diesel engines are considered steady torque engines?

Diesel engines are considered "steady torque", which means that torque is same no matter the revolutions whereas torque depends on revolutions for an engine that runs on Otto cycle. What is the reason for this?
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