Question: What mechanical engineering principles does Lennox International use in its HVAC products?

Context paragraphs:
Lennox International: Lennox International Inc. () is an intercontinental company.  Through its subsidiaries, it is a provider of climate control products for the heating, ventilation, air conditioning, and refrigeration markets around the world.  The Company was founded in 1895, in Marshalltown, Iowa, by Dave Lennox, the owner of a machine repair business for railroads.  He designed and patented a riveted steel coal-fired furnace, which led to numerous advancements in heating, cooling and climate control solutions.  The company was sold in 1904 to DW Norris who managed the company until his death in 1949, following which ownership devolved to his descendants who continued to hold a prominent position in the company in the following decades.

Frederick Winslow Taylor: Frederick Winslow Taylor (March 20, 1856 – March 21, 1915) was an American mechanical engineer who sought to improve industrial efficiency.  He was one of the first management consultants.  Taylor was one of the intellectual leaders of the Efficiency Movement and his ideas, broadly conceived, were highly influential in the Progressive Era (1890s-1920s).  Taylor summed up his efficiency techniques in his 1911 book "The Principles of Scientific Management", which in 2001 Fellows of the Academy of Management voted the most influential management book of the twentieth century.  His pioneering work in applying engineering principles to the work done on the factory floor was instrumental in the creation and development of the branch of engineering that is now known as industrial engineering.  Taylor made his name in, and was most proud of his work in, scientific management; however, he made his fortune patenting steel-process improvements.  Taylor was also an athlete who competed nationally in tennis and golf.

Roy Crawford: Robert James "Roy" Crawford {'1': ", '2': ", '3': ", '4': "} was a university administrator and mechanical engineering academic, whose primary research interest has been in the mechanical properties and processing behaviour of plastics.  From 1989 to 1999 he was Professor of Mechanical Engineering and Director of the School of Mechanical and Process Engineering at the Queens University Belfast in Northern Ireland.  He was also responsible for establishing the Polymer Processing Research Centre at Queens University.  This centre included the Research Group on rotational moulding of plastics, which he also established.  From 1999 to 2001 he was Professor of Mechanical Engineering at the University of Auckland in New Zealand.

Glossary of HVAC terms: HVAC (heating, ventilation, and air conditioning) is a major subdiscipline of mechanical engineering.  The goal of HVAC design is to balance indoor environmental comfort with other factors such as installation cost, ease of maintenance, and energy efficiency.  The discipline of HVAC includes a large number of specialized terms and acronyms, many of which are summarized in this glossary.

Grinnell Mechanical Products: Grinnell Mechanical Products, a brand of Tyco International Ltd., manufactures grooved piping and mechanical products.  Grinnell Mechanical Products specializes in mechanical, fire, HVAC, commercial, mining, institutional and industrial applications.  Grinnell grooved products are used in various industries because they are historically more efficient than flanged, welded, and threaded pipe joining methods.  Key product lines include grooved couplings and fittings, G-PRESS systems, strainers, stainless steel systems, copper systems, and G-MINE PVC systems.  Grinnell Mechanical Products offers mechanical services used for supporting engineering and design.  These include 2D and 3D drawings for the mechanical room and design suggestions and easy to follow installation drawings with legends for each pump.

Westaflex: Westaflex is a large global HVAC brand, owned by German company Westaflex Holding.  The company began in 1933 when Lorenz and Ferdinand Westerbarkey, formerly prisoner of war during the Nazi era developed a coil-based tube forming machine, the first stable and any-shape tube of its kind.  The company's owner, named it "Westaflex", from their family name "Westerbarkey" (meaning Westerflex HVAC products).

Food engineering: Food engineering is a multidisciplinary field which combines microbiology, applied physical sciences, chemistry and engineering for food and related industries.  Food engineering includes, but is not limited to, the application of agricultural engineering, mechanical engineering and chemical engineering principles to food materials.  Food engineers provide the technological knowledge transfer essential to the cost-effective production and commercialization of food products and services.  Physics, chemistry, and mathematics are fundamental to understanding and engineering products and operations in the food industry.

HVAC: Heating, ventilation, and air conditioning (HVAC) is the technology of indoor and vehicular environmental comfort.  Its goal is to provide thermal comfort and acceptable indoor air quality.  HVAC system design is a subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics, and heat transfer.  Refrigeration is sometimes added to the field's abbreviation as HVAC&R or HVACR, or ventilating is dropped, as in HACR (as in the designation of HACR-rated circuit breakers).

List of Historic Mechanical Engineering Landmarks: The following is a list of Historic Mechanical Engineering Landmarks as designated by the American Society of Mechanical Engineers since it began the program in 1971.  The designation is granted to existing artifacts or systems representing significant mechanical engineering technology.  Mechanical Engineering Heritage Sites are particular locales at which some event or development occurred or which some machine, building, or complex of significance occupied.  Mechanical Engineering Heritage Collections refers to a museum or collection that includes related objects of special significance to, but not necessarily a major evolutionary step in, the historical development of mechanical engineering.

Mechanical engineering technology: Mechanical Engineering Technology is the application of engineering principles and technological developments for the creation of useful products and/or production machinery.

Supporting paragraphs: Lennox International HVAC
Answer: thermodynamics, fluid mechanics, and heat transfer.