Temperature Increases viscosity decreases . viscocityis depends on surface area.surface area is more dragging force or viscous force is less. And also depends on velocity gradient.
F = - n .A. dv/dx. n is the coefficient of viscosity. dv/dx is the velocity dradient.
Areal size is more viscosity will be less .In such case temperature is less also.It is depends on the density of the fluid also.
Thanking you.
Having lived north of the 60th I'm used to heating fuel, propane etc. jell up. The most common solution used was to install a pad heater(75-150watt)on the tank. Besco was the brand name we used.
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The only reason I know to add kerosene to heating oil,ie desiel fuel, is to stop or prevent gelling. Kerosene will heat up disel fuel and prevent gelling actually that is what is in the bolltes they sell for that problem. Too much kerosene and your furance may burn to hot and be damaged or cause fires and other damage with extreme heat over theheaters parts ratings.
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You can reduce the viscosity of furnace oil by just adding THERMOL, a product from M/s ABHITECH ENERGYCON LTD, Mumbai in the ratio of 1:2000 by volume. the product costs about 450 to 500 Rs per litre and the manufacturers also claim a very good combustion without any nozzle chocking and clear smoke from the chimney.