Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[STEMO]

I've asked this question before, without receiving a satisfactory answer. How does a dpf stop particles being blown out of the exhaust when, surely, they must do it when self cleaning? Turns out they don't:

https://www.thisismoney.co.uk/money/cars/article-7879833/New-diesel-cars-exceed-particle-limits-EU-environmental-group.html

[Marks DTM Calib]

I've asked this question before, without receiving a satisfactory answer. How does a dpf stop particles being blown out of the exhaust when, surely, they must do it when self cleaning? Turns out they don't:

https://www.thisismoney.co.uk/money/cars/article-7879833/New-diesel-cars-exceed-particle-limits-EU-environmental-group.html

What you have to consider is that particulates are combustible (but have not been combusted in the cylinders).

So when the DPF regens, it gets very hot (circa 600 degrees C) and this combusts them, they can only pass through the DPF once burnt

[STEMO]

I've asked this question before, without receiving a satisfactory answer. How does a dpf stop particles being blown out of the exhaust when, surely, they must do it when self cleaning? Turns out they don't:

https://www.thisismoney.co.uk/money/cars/article-7879833/New-diesel-cars-exceed-particle-limits-EU-environmental-group.html

What you have to consider is that particulates are combustible (but have not been combusted in the cylinders).

So when the DPF regens, it gets very hot (circa 600 degrees C) and this combusts them, they can only pass through the DPF once burnt

I understand that, Mark, but the side product of that combustion still must be pretty unpleasant.

[Marks DTM Calib]

I've asked this question before, without receiving a satisfactory answer. How does a dpf stop particles being blown out of the exhaust when, surely, they must do it when self cleaning? Turns out they don't:

https://www.thisismoney.co.uk/money/cars/article-7879833/New-diesel-cars-exceed-particle-limits-EU-environmental-group.html

What you have to consider is that particulates are combustible (but have not been combusted in the cylinders).

So when the DPF regens, it gets very hot (circa 600 degrees C) and this combusts them, they can only pass through the DPF once burnt

I understand that, Mark, but the side product of that combustion still must be pretty unpleasant.

Mainly CO2 and water, not nearly as unpleasant as particulates and NOx

[STEMO]

I've asked this question before, without receiving a satisfactory answer. How does a dpf stop particles being blown out of the exhaust when, surely, they must do it when self cleaning? Turns out they don't:

https://www.thisismoney.co.uk/money/cars/article-7879833/New-diesel-cars-exceed-particle-limits-EU-environmental-group.html

What you have to consider is that particulates are combustible (but have not been combusted in the cylinders).

So when the DPF regens, it gets very hot (circa 600 degrees C) and this combusts them, they can only pass through the DPF once burnt

I understand that, Mark, but the side product of that combustion still must be pretty unpleasant.

Mainly CO2 and water, not nearly as unpleasant as particulates and NOx

These reports are wrong, then? If so, they should be challenged by the industry because, as far as I can see, a rush back to petrol would see CO2 levels go through the roof.
It's no good suggesting to people like me that an EV would be the way to go, because I've nowhere to plug one in. Hybrids are a waste of time, in my opinion. The battery has to be charged by a petrol engine while driving along so, by working to both propel the vehicle and charge the battery, they are emitting more CO2 than by just driving. You don't get the battery energy for free.

[STEMO]

As for the regenerative braking and charging going downhill, that wouldn't put enough charge in any hybrid I was driving. Nor Lord Opti, living in flat earth country.

[Varche]

Won’t be long before you ( your car ) are banned from city centres.  Mind you by then you will have an electric car.( charged wirelessly)

Back on the subject of regens, do some diesels do them without the driver noticing?

[STEMO]

Won’t be long before you ( your car ) are banned from city centres.  Mind you by then you will have an electric car.( charged wirelessly)

Back on the subject of regens, do some diesels do them without the driver noticing?

Most regen without any fuss. I know when my 2.0 astra with the fiat engine is doing it because the revs are at 950 instead of 850 at idle. I also know if I've switched off before the regen is complete because the cooling fans have to bring down the temperature of the dpf when you stop, and they go into hyperdrive 
The wife's astra, with the GM 1.6 whisper engine, gives no indication whatsoever, and the fans never kick in when she switches off. It was the same with her Renault 1.5dci.

[STEMO]

If you interrupt the regen cycle too often, a symbol lights on the dash and you get a message telling you to keep driving.

[STEMO]

Far too complicated for the average commuter. As Nick W said, it's no use putting symbols, lights and messages on the dash, because people don't understand them, so there are scared of them, so they wouldn't sell many diesels.
And car salespeople will just quickly gloss over it.

[Sir Tigger KC]

Won’t be long before you ( your car ) are banned from city centres. Mind you by then you will have an electric car.( charged wirelessly)

Back on the subject of regens, do some diesels do them without the driver noticing?

I think in the future EV's will have a solar skin like a wrap, that will be suitably advanced to charge the battery even in a grim place on a grim day. 

[LC0112G]

Won’t be long before you ( your car ) are banned from city centres. Mind you by then you will have an electric car.( charged wirelessly)

Back on the subject of regens, do some diesels do them without the driver noticing?

I think in the future EV's will have a solar skin like a wrap, that will be suitably advanced to charge the battery even in a grim place on a grim day. 

Do the maths.....

The typical UK sunlight energy density is somewhere between 20W and 200W per square metre depending on time of year.

https://www.withouthotair.com/c6/page_38.shtml

A car is what? 2m wide and 4m long? So 8 sqM. Therefore the available energy hitting the car is somewhere in the 160W to 1.6kW range. At midday. On a sunny day.

GCSE question : Write your name in block capitals at the top of the paper...

O Level question...Modern Tesla cars use batteries in the 60-120KWh range. How long is it going to charge a 60KWh Tesla battery on a sunny noontime day in June.

AO/A level question...- it's only sunny 32% of the time in the UK (apparently). And sunlight distribution is basically raised Cosine distributed about noon. How long to reach 80% charge on a 120kwh battery in March?

Degree question : Where's the JCR/Student Union Bar?   

[STEMO]

All of this is, by and large, moot. People (me) will only adopt eco friendly cars* when we are forced to. Why? Well 1) It costs money 2) Most people realise that, even if this country turned zero emissions overnight, it wouldn't make a jot of difference to the world as a whole.

My diesel emits particulates which harm people on busy roads in densely populated areas, I don't live in such a place. A switch to petrol would mean emitting CO2, which kills the whole planet, apparently.

IMO, hybrids are not eco friendly cars.

[Sir Tigger KC]

Won’t be long before you ( your car ) are banned from city centres. Mind you by then you will have an electric car.( charged wirelessly)

Back on the subject of regens, do some diesels do them without the driver noticing?

I think in the future EV's will have a solar skin like a wrap, that will be suitably advanced to charge the battery even in a grim place on a grim day. 

Do the maths.....

The typical UK sunlight energy density is somewhere between 20W and 200W per square metre depending on time of year.

https://www.withouthotair.com/c6/page_38.shtml

A car is what? 2m wide and 4m long? So 8 sqM. Therefore the available energy hitting the car is somewhere in the 160W to 1.6kW range. At midday. On a sunny day.

GCSE question : Write your name in block capitals at the top of the paper...

O Level question...Modern Tesla cars use batteries in the 60-120KWh range. How long is it going to charge a 60KWh Tesla battery on a sunny noontime day in June.

AO/A level question...- it's only sunny 32% of the time in the UK (apparently). And sunlight distribution is basically raised Cosine distributed about noon. How long to reach 80% charge on a 120kwh battery in March?

Degree question : Where's the JCR/Student Union Bar?

I said 'in the future'.  I didn't say how far into the future.   

[Sir Tigger KC]

All of this is, by and large, moot. People (me) will only adopt eco friendly cars* when we are forced to. Why? Well 1) It costs money 2) Most people realise that, even if this country turned zero emissions overnight, it wouldn't make a jot of difference to the world as a whole.

My diesel emits particulates which harm people on busy roads in densely populated areas, I don't live in such a place. A switch to petrol would mean emitting CO2, which kills the whole planet, apparently.

IMO, hybrids are not eco friendly cars.

Diseasels emit CO2 as well.