Exhaust air flow sensor

Exhaust air flow sensor may be used for the fresh air, dirty air, mix gas flow measurement, and also could be used in large pipeline or ducts or chimneys, such as HVAC air flow measurement, flue gas from incinerator, engine exhaust gases, solution for flue gas mass flow measurement in Power plant, very aggressive exhaust flue gases from marine diesel engines, gas flow in a semiconductor exhaust system, exhaust flow coming out of furnace, hot air, flue gases feed a waste heat recovery boiler, exhaust pipe from furnace , to get read from airflow in a vacuum pipe system exhausting air from a process, hot exhaust gases.,etc.
These applications can be very tough, because it can mix air, dirty air, hot air, high temperature gas or gas, low velocity and high pipeline size. However insertion thermal mass flow meter can be an affordable solution for exhaust air flow measurement, in a word, it can be a good exhaust air flow sensor.

Principle of Exhaust air flow sensor

Exhaust air flow measurement can be carried by thermal flow meter, thermal gas mass flow meters use thermal diffusion technology for exhaust air flow measurement. There are 2 temperature detection elements (Pt1000 platinum resistance) in the measuring probe, the heated end ACT, the unheated end REF and a constant heat source. REF is used to measure the temperature of the exhaust air itself, and it is used as the reference end; ACT is close to the constant heat source, and measures the temperature of the surface of the constant heat source after the heat is taken away by the exhaust air, which is the measurement end. The change in the temperature difference between the measuring end and the reference end is directly proportional to the gas or exhaust air mass flow rate.
When the exhaust air flows over the sensor surface, it will take away the heat on the surface of the measuring end and the temperature difference will change. Different composition exhaust air and different flow rates take away different heat. The exhaust gas mass flow is derived from the change in the temperature difference.

Features of Exhaust air flow sensor

• Thermal mass flow meter take exhaust air direct mass flow measurement: measure mass flow in real time, without temperature and pressure correction
• Air flow sensor has wide range ratio 100:1 to suitable large ducts or pipelines or rectangular ducts, also suitable for exhaust air running at low flow velocity;
• No pressure loss: when the air, HVAC air flow rate is 4000m3/h, pressure loss can be as low as 90Pa in a pipe with a diameter of 1000mm.
• Exhaust flue gases flow sensors are easy to install: for insertion type gas flow meter, only 1 mounting hole is needed, and the optional hot cap can be installed under pressure. The sealing device can be plugged and unplugged online, and it is completely pre-calibrated, saving installation and adjustment time.
• Low maintenance: no moving parts, no small holes, no clogging, no drift, no need for regular maintenance
• High reliability, long trouble-free time even for hot flue air or gas, exhaust flow from furnace or boiler.,etc
• It is easier for gas mass flow meters to obtain the guarantee of measurement accuracy and measurement stability. Thermal sensors are unaffected by the cleanliness of the gas and are virtually maintenance-free.
• Exhaust air flow sensors has many sensor size options , such as 1”,2”,3 inch, 4 inch, 6”,8”, 10”, 14”.16,20 inches or more, DN100,DN200,1000mm pipe diameter, Chimney diameter 2 meters,3 meters or even more;
• Exhaust air is normal mix air or corrosive air, with content of CO2, H2O, H2SO4, H2O2, HCL, Nitrogen,CO,NOx.,etc, air sensor is made with stainless steel 316 to fit the tough air measurement job.
• Digital exhaust air flow sensor can be with LCD display to show air flow rate at normal or standard condition, also total air flow can be indicated. Air flow units options: g/min, g/s, Kg/min, Kg/h,Nm3/h,Nm3/min,NL/h,NL/min,SCFM ,total air flow unit options: g,Kg,Nm3,NL,CFM;
• Exhaust air flow transmitters have 4-20Ma current outputs or MODBUS RTU for remote control and inspections.

Exhaust air flow sensors is low price flow meter

Judging from the actual use, the thermal gas mass flowmeter has the characteristics of simple installation, large range ratio, fast response speed, high accuracy, reliability, and low loss, and achieves the effect of energy saving, the important part is that it is low price cost, insertion thermal mass flow meter price starts from 700 USD. Thermal mass flow meter technology used for exhaust air, flue gas, hot air, engine exhaust gas, HVAC air mass flow measurement is currently a relatively advanced technology, and it has high economic and practical value for domestic waste incineration power plants to replace traditional flow measurement devices or mass flow measurements to adjust diverter valves to improve boiler efficiency.