Leave it up to the engineering nerds here to keep it interesting [8D]
Do reefers commonly get refueled in Chicago if they are going from the West to East Coast? Do the Railroads do this like UP or the company transporting the perishables?
Thanks.
No motorhome or camping trailer owners on this blog? Most have dual fuel refrigerators that run on either propane or electricity. I have a portable Dometic unit that runs on 12v dc, 120v ac or propane. It is an adsorption unit similar to Servels which my parents had back in 1940. But the propane is an open flame and this is restricted in tunnels and other locations. No means to provide defrosting.
Another issue is that the cooling units on the trucks and container require a circulating fan to blow the cold air through the load. Just as most modern refrigerators do. So it is my belief that the conversion from diesel to gas would require a conversion to electric generation to supply electric cooling units.
they get refueled at Delano or the one in WA. i am pretty sure a third party fuels the railcars.
Doesn’t work like that today.
In the defrost cycle, HOT dry air is circulated (I believe from the neighborhood of the condenser), in some kind of crossflow, through the air space between food items and side sheets. This cycle happens fairly frequently, but for only a short time each time, so that opening and closing of the doors and leakage at the seals doesn’t allow ‘frost’ to build up more than a light rime.
This is why if you pack food too tightly in your freezer the ice can back up to foul the little fan that circulates the air, or build up more dramatically in areas where the airflow is impeded. This is also part of the reason why delicate items may not do well in the freezer – a measurable percentage of the time there is actually warm, dry air impinging on the frozen items, with the assumption that since they themselves are ‘bulk frozen’ no part of them will warm up to the unsafe range during the time the frost is subliming.
If you get frost buildup to the point there is liquid when you defrost, the built-in system has utterly failed. Or you have REALLY had the freezer door open a lot with high humidity outside, or tried to freeze stuff that has a high water content and was put in unfrozen.
I get the impression that most freezer vans or containers cube out before they weigh out, and are packed and dunnaged in with little space between them, so periodic defrost is not going to work well. This might be addressed with a dehumidifier stage, or dessicant wheel or whatever, drying humidity out of any air circulated in the container during stuffing or stripping, and then really good humidity sealing at the doors and seams en route.
The answer is just plain NO. In transporttation weight is money. IT cost $ to move evry pound , payload or not. The local Anheuser Busch distributer in a feel good move has put on a bunch of CNG delivery trucks. These single axle tractors appear to have a sleeper cab which on closer examination , is the fuel tanks. With these huge fuel tanks, quite heavy probably 3/8" steel, they have a range of about 200 miles max. And a loss of about 30% in power. With Diesel the range would be probabaly be 400 miles.
I’ll just say this having hauled reefers with trucks . Even though a lot of truck stop have NG fueling it would be an headache to have to pull to a separate bay to refuel the reefer and the fact is you would spend all your time either looking for fuel for thebreefer