Thermometric apparatus and method for determining the concentration of a vapor in a gas stream

A method of making a sensor for determining the concentration of a vapor of a liquid in a gas stream:

• substantially surrounding a temperature sensor with a non-woven, non-flaking, liquid-permeable member (LPM) comprising one of a porous membrane, a gel, and a combination thereof, the LPM wherein heat loss due to evaporation of the liquid from the LPM when wet with the liquid and in a gas stream will result in a temperature sensed by the temperature sensor being lower than the temperature of the gas stream, the temperature of the temperature sensor when wet and the temperature of the gas stream being determinable to determine the concentration of the vapor in the gas stream.

A method for sensing the humidity of a volatile liquid in a gas stream, comprising:

• (a) sensing the temperature of the gas stream;
• and
• (b) using a thermal sensor to measure the temperature of a medium surrounding the thermal sensor in the gas stream, the medium being continuous from the thermal sensor to a body of supply of the liquid remote from the thermal sensor, the liquid proximate to the thermal sensor being confined by a substantially non-woven, non-flaking, water-permeable member (LPM) comprising one of a porous membrane, a gel, and a combination thereof in the gas stream, wherein heat loss due to evaporation of the liquid from the LPM when wet with the liquid will result in a temperature lower than the temperature of the gas stream, said lowering in temperature being determinable to determine the humidity in the gas stream.

A sensor for sensing the concentration of a vapor of a liquid in a gas stream, comprising:

• a wetable temperature sensor having a heat sensitive part, the heat-sensitive part being surrounded by a liquid medium that is continuous from the heat-sensitive part to a body of liquid supply;
• and
• a non-woven, non-flaking, liquid-permeable member (LPM) substantially surrounding the heat sensitive part of the wetable temperature sensor, wherein heat loss due to evaporation of the liquid when the LPM wet with the liquid is placed in the gas stream will result in the temperature sensed by the wetable temperature sensor being lower than the temperature of the gas stream, the lowering in temperature being determinable to determine the concentration of the vapor in the gas stream, the LPM has a channel containing the liquid and the wetable temperature sensor has electrical wires extending into the channel to transmit electrical signal from the wetable temperature sensor corresponding to the temperature sensed thereby.