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- From: bloom@inland.com
- Newsgroups: rec.models.rc
- Subject: Re: Thermodynamic laws
- Message-ID: <1992Sep9.090743.2290@inland.com>
- Date: 9 Sep 92 09:07:43 CST
- References: <1992Sep8.170741.8431@magnus.acs.ohio-state.edu>
- Organization: Inland Steel Company; East Chicago, IN
- Lines: 23
-
- In article <1992Sep8.170741.8431@magnus.acs.ohio-state.edu>, mtissand@magnus.acs.ohio-state.edu (Michael D Tissandier) writes:
- > PV=nRT is not a thermodynamic law, it is an equation of state. In the
- > absence of compression v. heat data for the additive combustion products,
- > it is possible to increase pressure without increasing temperature. In
- > the equation, 'n' stands for moles of gas, if this were to increase due
- > to an additive, the pressure could increase without adjusting the temperature
- > of the reaction. The question of running temperature effects due to
- > additives is completely empirical in nature.
- >
- > --Mike
-
- While it is true that 'n' can be adjusted upward to increase P without
- changing T, and if you balance the chemical reactions you will find that
- burning 100% nitro methane vs 100% methanol does produce more moles of
- combustion products, you will also find that the heat of reaction is
- greater for burning the nitro (if you use the same amount of oxygen from
- the air!). Now since you are not going to significantly change the
- efficiency of your heat engine by substituting fuel, and your efficiency is
- in the neighborhood of 30-40% at best, then this extra energy is just
- going to increase the temperature of your engine. For those who want to
- know how to increase the efficiency of their engine.....you just build
- it our of ceramic materials so less heat is lost to the air and your
- energy is more completely converted to driving the piston.
-