Some Characteristics of the Force in a Radiometer

L. Thompson

Extensive literature is on the radiometer and its rarefied gas reactions. On the other hand, little attention seems given to the characteristics of the force itself. The purpose of this paper and the testing is to show some of these characteristics. 

The equipment used is a 1/2 hp vacuum pump. The vacuum chamber is 10 inches in diameter with 1/4" thick polycarbonate walls. A 60w halogen spot light projects light and radiant energy.  I am using a digital scale accurate to 0.01 gram. 1 radiometer vane weighs about 0.06g and the 4 vanes and harness weigh 0.6g. The smallest surface area used in the testing weighed about .002 gram (extrapolated from the weight of a larger surface area).  The units of vacuum measure are:  1/760 atmosphere = 1 torr.  1 torr = 1000 microns.

I am observing the application of a net force overcomes the inertia of the vanes and harness. The rotating vanes of the radiometer are similar to a flywheel, except the force is generated close to the vane surface. I observe a small force is inputted, as in a "momentum pump", to increasing the momentum of a larger mass. In well balanced vanes the increasing  momentum can reach 2000 to 3000 RPM.

The radiometer vanes begin to show some force effects around 1000 microns. The testing to date is in the partial vacuum range of  100 to 300 microns. In this range the radiometer vanes and harness, when placed in the vacuum chamber as a control check, show a similar response as in a radiometer.

Many variables can be changed to increase or decrease the net force, such as temperature, heating, rarefied gas used, mass, inertia, spacing, shape of the surfaces, type of materials, and partial vacuum.  My impression is that different areas of physics are needed to explain the generated force.

In in atmospheres above 1000 +/- microns the crowding effects of the gas molecules prevent movement. In high vacuums there is no movements due to too few molecules.  In the micron range of 10+/- microns pressure differentials are not present as the individual molecular spacing is too great for pressure differentials to work.

Much of what is taking place in a radiometer is not visible. Yet out of  the complexities presented and of the rarefied gas reactions is also simplicity. This simplicity is: the radiometer vanes spin in response to the input of energy or to the taking out of energy (the "refrigeration effect").  In the testing  I am using this simplicity to demonstrate the characteristics of the resulting force.

Notes and Observations

A. In the radiometer the net force results in centrifugal acceleration. The initial testing shows I need to respect this rotational nature - as if the force needs to "push itself" into a lower pressure area.

B. When the rarefied gas molecules transfer momentum/energy, the molecules cool. This cooling, simultaneously taking place with the input of molecular energy/momentum into the momentum of the vanes, would represent the "exhaust side" of the generated power.

I have in the testing to date a demonstration of this effect. I removed the vanes to put the vanes and pedestal in the vacuum chamber as a control check. However I first broke the small tube at the radiometer base to let in air/oxygen. I then applied a strong radiant heat source (the 60w halogen)  to the vanes (still mounted in the radiometer).  I wanted to see if convection currents could cause vane rotation. There was little or no movement. A cloud of smoke erupted. One vane turned partially brown. Yet prior to this when the vanes where fully in the radiometer and before breaking the sealing tube I applied the same radiant energy source. The vanes turned rapidly.  I feel the spinning radiometer vanes, with the input of energy into momentum, were running cooler. There was also more time in the rotation itself to dissipate excess heat as re-radiated radiant energy. Then when the vacuum was released to a full atmosphere and the vanes could no longer rotate, oxygen combustion took place due to the excessive heating. It is my feeling that, even without oxygen for combustion, that the stationary vanes would have melted or charred with the the continued application of radiant energy.

This testing shows excessive weight and/or friction preventing vane movement  results in wasted heating.  The energy will not be put into propelling the mass to which the force is directed.

C. In the testing the gas molecules are recharged and reused. There is no external exhaust. I am curious about this characteristic as, in effect, the rarefied gas molecules are  trapped to do work with the input of energy, over and over. (Perhaps the force will always be too small for application and this special property would remain in the realm of science fiction.)

D. I would like to give some thought to radiant energy in dispelling excess energy. I have had a surprise  that with the excessive input of radiant energy, the vanes first spin clockwise then upon cooling the vanes spin in the opposite, counter clockwise direction. I feel this could be due to radiant energy radiating at a faster rate from the carbon black surface- thus creating an opposite pressure differential.  (This is likely the same as the refrigeration effect.  I recall reading of the vanes spinning opposite when a radiometer is first taken out of a refrigerator.) 

E. In my general reading on the radiometer  little attention seems given to the reason for the initial energizing of the rarefied gas molecules. I feel this initial energizing could involve Newtonian physics as the gas molecules would be striking the irregular carbon black soot surface from various angles and over short molecular time intervals. As individual molecules the molecules could not overcome the much larger mass inertia of the radiometer vanes and harness. Then the rarefied gas molecules, acting in concert via the  pressure differential  between the reflective and non reflective sides, could then over come the inertia of the vanes and harness.

The end result could be a force with no initial equal and opposite offsetting reaction and seemingly counter to Newtonian Physics. Yet this net force could have its base in Newton's physics - that a small force, as in a bouncing ball, may not over come the inertia of a  larger mass.

F. My understanding of radiant energy is little or no force would be exerted on the radiating mass. Hence in addition to the bouncing ball example, it could also be possible to create an imbalance when excess radiant energy is re-radiated out of the system (as in the refrigeration effect noted above).

I am working with the above notes in the testing.  Rather than go into the details of the initial testing, I feel the following notes suffice until further testing is in place, either by myself or by others.

I have confirmed that  carbon soot on aluminum works also works. It may be the carbon surface is able to provide the necessary insulation for the pressure differential.  I compared both paper and aluminum. I first observed the same limited motion in both.  As the soot is easier to apply on the aluminum I am using aluminum as the base.  (Note as both carbon and aluminum are radiating surfaces I would anticipate the "refrigeration effect"  would not work with aluminum.)  However further testing could be warranted to compare the net force being  generated  with insulating surfaces of various thickness versus carbon on aluminum. 

On 12/14/2010 I confirmed with a light weight carbon aluminum strip hanging with an off center hole on a 0.10 carbon fiber rod that it was possible to move the strip down the rod.  The strip moved first with agitation a little down the rod then rapidly with a full circular motion around and down the rod. Extrapolating the weight from a larger aluminum strip the weight is about 0.002 grams.  ( I would like a reconfirmation of this with an outside testing facility.)

After this demonstration I feel unless I can work with a well balanced system as in the 0.6 gram weight of the radiometer vanes and harness, that I need to work with smaller mass weights.

I am now almost certain that oscillations are necessary. This helps explain why I was not able to get heavier and larger strips to move over a rod or over two parallel rods even though I was observing a little back and forth movement. It helps explain why the control mounted radiometer vanes spin rapidly whereas the strips on one rod and then on two parallel  rods showed little motion. 

It is also my feeling the pressure differentials from the opposite side of the strips could be meeting on the opposite, reflective side resulting in the same pressure on both sides. Also hindering the above testing was the unequal, small movement of the strips was causing the strips to bind on the rod or rods.

Yet, if needing further confirmation of the necessity for oscillations, the small, light weight aluminum strip with its off center hole spun wildly around the rod as it moved down the rod.  The degree of energizing looked to me to match that of the radiometer vanes upon the application of a strong energy source.

In observing the spinning radiometer vanes the net force is directed into a centrifugal acceleration. Yet after observing the small spinning  aluminum strip, the required  movement into a lower pressure area also has a directional component which is not fully rotational in nature. (It is this non rotational component which may lead to the unique properties I had predicted in earlier papers.)

What is intriguing in the radiometer is the almost simultaneous deceleration of the gas molecules to give the net acceleration. This deceleration is being "masked" by the net acceleration which is then viewed as the movement of the vanes and harness.  From the time of Newton, physics is focused on the taking apart and quantifying force. I feel the radiometer force, in contrast, is a composite force including the almost simultaneous deceleration of the rarefied gas molecules to give the net accelerative force.

1. At a low micron range where pressure differentials are not present, the individual atoms predominate. I would like testing  in say the 10 - 20 micron  range. 

2. The testing is the determination of what is possible in physics.

3. Testing is to be with the supervision of those with experience in vacuum safety. 

A next step would be to direct the internal radiometer force to the entire light weight shell mounted within the vacuum chamber. This testing could further demonstrate the net force in a radiometer is from an internally directed force.

If a reader would be interested in taking this on, I could offer additional insights.

Reference   http://math.ucr.edu/home/baez/physics/General/LightMill/light-mill.htm

 lance@pon.net   January 7, 2012  (minor changes)